Lexus LS400 2000 User Manual

BE–1

–BODY ELECTRICAL BODY ELECTRICAL SYSTEM

BODY ELECTRICAL SYSTEM

BE0DC–01

PRECAUTION

Take care to observe the following precautions when performing inspections or removal and replacement
of body electrical related parts.

1. SUPPLEMENTAL RESTRAINT SYSTEM (SRS)

The Lexus LS400 is equipped with an SRS (Supplemental Restraint System) such as the driver airbag and
front passenger airbag. failure to carry out service operation in the correct sequence could cause the SRS
to unexpectedly deployed during servicing, possibly leading to a serious accident. Before servicing (includ­ing removal or installation of parts, inspection or replacement), be sure to read the precautionary codices
in the RS section.

2. COMBINATION METER SYSTEM

The cold cathode tube connectors (Connectors ”N”, ”P” and ”Q”) in the combination meter are charged with
high voltage AC current when power is supplied, so do not touch them when they are charged.

3. MICRO COMPUTER PRESET DRIVING POSITION SYSTEM
Power Seat Control System
Power Mirror Control System
Power Tilt and Telescopic Steering System

If the battery negative (–) terminal is disconnected, the preset driving positions stored in memory are erased,
so be sure to note the positions and reset them after the battery terminal is reconnected.

4. AUDIO SYSTEM

! If the battery negative (–) terminal is disconnected, the preset AM, FM 1 and FM 2 stations stored in

memory are erased, so be sure to not the stations and reset them after the battery terminal is recon­nected.

! If the battery negative (–) terminal is disconnected, the ”ANTI–THEFT SYSTEM” will operate when the

terminal is reconnected, but the radio, tape player and CD player will not operate. Be sure to input the
correct ID number so that the radio, tape player and CD player can be operated again.

2000 LEXUS LS400 (RM717U)

1864Author!: Date!:

BE–2

–BODY ELECTRICAL BODY ELECTRICAL SYSTEM

5. MOBILE COMMUNICATION SYSTEM

If the vehicle is equipped with a mobile communication system, refer to precautions in the IN section.

6. LIGHTING SYSTEM

! Halogen bulbs have pressurized gas inside and require special handling.

They can burst or scatter if scratched or dropped. Hold a bulb only by its plastic or metal case.
Don’t touch the glass part of a bulb with bare hands.

! When high voltage socket of discharge headlight is touched with the light control switch HEAD, high

voltage of 20,000 V is momentarily generated. This might lead to a serious accident.

! Never connect the tester to the high voltage socket of discharge headlight for measurement, as this

leads to a serious because of high voltage.

! When performing operation related to the discharge headlight, make sure to do it in the place with no

water of rain to prevent electric shock, with light control switch OFF, battery terminal removed, connec­tor of light control ECU disconnected.

! When performing operation related to the discharge headlight, make sure to do it after assembling has

been completely over and never light up without a bulb installed.

! Do not light up the discharge headlight using another power source except vehicle’s.
! When there is a defect on the discharge headlight or any shock has been applied to it, replace the light

with a new one.
Even if the light operates normally, there is a possibility that the fail–safe function not works.

2000 LEXUS LS400 (RM717U)

1865Author!: Date!:

BE–256

N13360

–

BE0DB–01

INSPECTION

1. INSPECT HORN SWITCH

(a) Disconnect the negative (–) terminal from the battery.
(b) Remove the left and right covers from the steering wheel.
(c) Using a torx socket wrench, loosen the 2 bolts.
(d) Pull up the horn pad and place it on the steering column,

as shown.
HINT:
Do not disconnect the connector from the horn pad.

6

(e) Disconnect the connector from the slip ring.
(f) Check that there is no continuity between terminal 6 of the

connector and body ground.
(g) Check that there is continuity between terminal 6 of the

connector and body ground when the horn contact plate

is pressed against the steering spoke assembly.
If continuity is not as specified, repair or replace the steering
wheel or wire harness as necessary.

I03247

(h) Install the horn pad in place and using a torx socket

wrench, torque the 2 bolts.

Torque: 7.1 N·m (72 kgf·cm, 62 in.·lbf)

(i) Install the left and right covers.
(j) Connect the negative (–) terminal to the battery.

2. INSPECT HORN OPERATION

Connect the positive (+) lead from the battery to the terminal
and negative (–) lead to the horn body and check that the horn
blows.
If operation is not as specified, replace the horn.

I03248

3. INSPECT HORN RELAY CONTINUITY

Condition Te s te r c o nn e c t i on Specified condition

Constant 1 – 2 Continuity

2

3

1

Z08505

Apply B+ between

terminals 1 and 2.

2 – 3 Continuity

If continuity is not as specified, replace the relay.

2119Author!: Date!:

HORN SYSTEM

LOCATION

BE–255

–

BE0DA–01

Engine Room Junction Block

! Horn Relay
! HORN Fuse

Horn

Horn Switch

I03238

2118Author!: Date!:

BE–254

–

BE0D9–01

INSPECTION

INSPECTION TRANSPONDER KEY COIL CONTINUITY

Check that there is continuity between terminal 1 and 2.
If continuity is not as specified, replace the coil.

N17185

2117Author!: Date!:

LOCATION

BE–253

–

BE0D8–01

Transponder Key
Coil

ECM

Transponder Key
Amplifier

I03461

2116Author!: Date!:

BE–244

–BODY ELECTRICAL ENGINE IMMOBILISER SYSTEM

ENGINE IMMOBILISER SYSTEM

BE0D7–01

REGISTRATION PROCEDURE

1. KEY REGISTRATION IN AUTOMATIC REGISTRATION MODE

(a) Registration of a new transponder key.
HINT:

! This must be done when you install a new ECM.
! The new ECM is on the automatic key code registration mode. The already fixed number of key codes

for this ECM can be registered.
On this type of vehicle, up to 4 key codes can be registered.

! In the automatic registration mode, the last key registered becomes sub–key.

START

Insert the key in the key cylinder.

Under registration

Registration completion

Remove the key.

Security indicator blinks until the first
key is inserted. The indicator lights up
after the key registration.

Security Indicator ON

Security Indicator
OFF

Yes

2000 LEXUS LS400 (RM717U)

Will you register the
next key?

No

END

Security Indicator ON
(After the last key (sub–key)
has been registered, the indi­cator goes off.)

2107Author!: Date!:

BE–245

–BODY ELECTRICAL ENGINE IMMOBILISER SYSTEM

HINT:

! When a key is not inserted in the key cylinder on the automatic registration mode, the security indicator

always lights on.

! When the immobiliser system operates normally and the key is pull out, the security indicator blinks.
! When key code registration could not be performed on the automatic registration mode, code 2–1 is

output from the security indicator and when inserting the already registered key, code 2–2 is output.

Blinks

1.2 Sec.

0.8 Sec.

0.25 Sec.

0.25 Sec. 0.5 Sec.

Code 2–1 Code2–2

1 Sec.

0.25 Sec.

0.25 Sec.0.5 Sec.

1 Sec.

(b) Automatic registration mode completion

If completing the mode forcibly when more than 1 key code have been registered on the automatic
registration mode, perform the following procedures.
After 1 more key code have been registered with master key, perform step (1) or (2) without pulling
the key out or inserting the already registered key.

(1) Depress and release brake pedal 5 times or more within 15 sec.
(2) With the LEXUS hand–held tester, require automatic registration mode completion.

2000 LEXUS LS400 (RM717U)

2108Author!: Date!:

BE–246

–BODY ELECTRICAL ENGINE IMMOBILISER SYSTEM

2. KEY REGISTRATION OF PROCEDURE NEW MASTER KEY AND NEW SUB–KEY ON THIS IS DE­SCRIBED BELOW

HINT:
Key registration of new master key and new sub–key on this vehicle when new ignition cylinder and key set,
and new lock cylinder set including ignition key cylinder are installed.

(a) Removing wire–less and immobiliser module from origi-

nal master key.

I04311

I04312

(b) Masking new master key.

After replacing and installing new ignition cylinder, install
removed original modules into new 2 key housing as sup­ply parts.

(c) Registration of supplied new sub–key and /or master key

Register supplied new sub–key and /or master key by us­ing new master key.
(See step 3 and 4)

NOTICE:
In case of replacing with ignition cylinder and key set, door
locks cannot be opened by new ignition keys. Therefore, to
avoid any trouble caused by empty battery of transmitter
of new ignition key, please bring the original key while driv­ing.

2000 LEXUS LS400 (RM717U)

2109Author!: Date!:

BE–247

–BODY ELECTRICAL ENGINE IMMOBILISER SYSTEM

3. REGISTRATION OF ADDITIONAL MASTER KEY

There are 2 ways for registration of additional master key, one way is depressing brake pedal and accelera­tion pedal and the other way is using LEXUS hand–held tester.
HINT:

! It is possible to register up to 7 master key codes including the already registered key code.
! When any operation time described below is over, registration mode completes.
! When the next procedure is performed while the timer is working, the timer completes counting time,

then next timer starts.

! When replacing ”Ignition Cylinder Key Set” or ”Lock Cylinder Set” and register according to the follow-

ing procedure using the original master key. However, after the registration of the additional master
key, as the original master key and the original sub–key is not necessary any more, so erase registra­tion of those key codes.
(1) Depressing brake pedal and acceleration pedal:

Insert already registered master key in the key
cylinder

Within 10 sec.

Depress and release the acceleration pedal 5
times.

Depress and release the brake pedal 6 times,
and remove the master key.

Insert key to be registered in key cylinder.

Depress and release the acceleration pedal 1
time. (Security indicator blinks)

After 60 sec. additional master key is registered.
(Security indicator is OFF)

Within 15 sec.

Within 20 sec.

Within 10 sec.

Within 10 sec.

2000 LEXUS LS400 (RM717U)

Yes

The registration mode completes when pulling
out the key and depressing and releasing the
brake pedal once or more within 10 secs. after
indicator has been off or 10 sec. have passed.

Will you register the
next key?

No

2110Author!: Date!:

BE–248

(2) Using LEXUS hand–held tester:

Insert already registered master key in the key cylinder.

Using LEXUS hand–held tester select master key regis­tration.

Remove the master key.

–BODY ELECTRICAL ENGINE IMMOBILISER SYSTEM

Within 120 sec.

Within 20 sec.

Within
10 sec.

Within 10 sec.

Insert key to be registered in key cylinder.
(Security indicator blinks)

After 60 sec., additional master key is registered.
(Security indicator OFF)

Yes

Will you register the
next key?

No

The registration mode completes when pulling
out the key and depressing and releasing the
brake pedal once or more within 10 sec. after in­dicator has been off or 10 sec. have passed.

2000 LEXUS LS400 (RM717U)

2111Author!: Date!:

BE–249

–BODY ELECTRICAL ENGINE IMMOBILISER SYSTEM

4. REGISTRATION OF ADDITIONAL SUB–KEY

There are 2 ways for registration of additional sub–key, one way is depressing brake pedal and acceleration
pedal and the other way is using LEXUS hand–held tester.
HINT:

! It is possible to register up to 3 sub–key codes including the already registered key code.
! When any operation time described below is over, registration mode completes.
! When the next procedure is performed while the timer is working, the timer completes counting time,

then next timer starts.
(1) Depressing brake pedal and acceleration pedal:

Insert already registered master key in the key
cylinder

Within 10 sec.

Depress and release the acceleration pedal 4
times.

Depress and release the brake pedal 5 times,
and remove the master key.

Insert key to be registered in key cylinder.

Depress and release the acceleration pedal 1
time. (Security indicator blinks)

After 60 sec. additional sub–key is registered.
(Security indicator is OFF)

Within 15 sec.

Within 20 sec.

Within 10 sec.

Within 10 sec.

2000 LEXUS LS400 (RM717U)

Yes

The registration mode completes when pulling
out the key and depressing and releasing the
brake pedal once or more within 10 sec. after in­dicator has been off or 10 sec. have passed.

Will you register the
next key?

No

2112Author!: Date!:

BE–250

(2) Using LEXUS hand–held tester:

Insert already registered master key in the key cylinder.

Using LEXUS hand–held tester select sub–key registra­tion.

Remove the master key.

–BODY ELECTRICAL ENGINE IMMOBILISER SYSTEM

Within 120 sec.

Within 20 sec.

Within
10 sec.

Within 10 sec.

Insert key to be registered in key cylinder.
(Security indicator blinks)

After 60 sec., additional master key is registered.
(Security indicator OFF)

Yes

Will you register the
next key?

No

The registration mode completes when pulling
out the key and depressing and releasing the
brake pedal once or more within 10 sec. after in­dicator has been off or 10 sec. have passed.

2000 LEXUS LS400 (RM717U)

2113Author!: Date!:

BE–251

–BODY ELECTRICAL ENGINE IMMOBILISER SYSTEM

5. ERASURE OF TRANSPONDER KEY CODE

There are 2 ways for erasure of transponder key code, one way is depressing brake pedal and acceleration
pedal and the other way is using LEXUS hand–held tester.

NOTICE:
Delete all other master and sub–key codes leaving the master key code to use the operation. When
using the key which was used before deletion, it is necessary to register the code again.

HINT:

! When any operation time described below is over, registration mode completes.
! When the next procedure is performed while the timer is working, the timer completes counting time,

then next timer starts.
(1) Depressing brake pedal and acceleration pedal:

1. Insert master key in the key cylinder.

Within 15 sec.

2. Depress and release the acceleration pedal 6 times.

3. Depress and release the brake pedal 7 times.

4. Remove the master key.

5. Leave the vehicle more than 20 sec. without any
operation.

Within 20 sec.

Within 10 sec.

HINT:

If the key cannot be pulled out within 30 sec. from the first brake
depression in the step 3, the key code deletion is canceled.

2000 LEXUS LS400 (RM717U)

END

(Key code erased)

2114Author!: Date!:

BE–252

(2) Using LEXUS hand–held tester:

1. Insert master key in the key cylinder.

2. Require key code deletion from hand–held tester.
(Security indicator blinks)

3. Remove the master key.

–BODY ELECTRICAL ENGINE IMMOBILISER SYSTEM

Within 120 sec.

Within 10 sec.

END
(Key code erased)

HINT:

When the key cannot be pulled out in the step 3, key code deletion is canceled.
(Security indicator is OFF.)

2000 LEXUS LS400 (RM717U)

2115Author!: Date!:

–

INSTALLATION

1. INSTALL GARAGE DOOR OPENER

(a) Connect the wire harness to the terminal 4 and 5.
(b) Install the 3 screws.

2. INSTALL FRONT PERSONAL LIGHT

(a) Connect the 2 connectors.
(b) Install the 3 screws.

3. INSTALL FRONT PERSONAL LIGHT LENS

BE–243

BE0D6–01

2106Author!: Date!:

I03241

I03242

BE–241

–BODY ELECTRICAL GARAGE DOOR OPENER SYSTEM

BE0D5–01

INSPECTION

1. INSPECT GARAGE DOOR OPENER

Press the switch and check that each LED (red) lights up.
Even if only one switch is found not to light up, replace it.

2. INSPECT GARAGE DOOR OPENER REGISTRATION
AND TRANSMITTING

HINT:
Use the home link tester made by KENT MORE for this test.
As it is necessary to record the code of the hand held transmit­ter, customer’s code will be erased. When the inspection com­pletes, please register the customer’s again.
(a) Check that the code of hand held transmitter for inspec-

tion can be recorded.
(See page

If the code can not be registered, replace garage door opener.

2000 LEXUS LS400 (RM717U)

(b) Press the switch which an inspection code has been reg-

istered for and check that LED (green) of the home link
tester lights up.

If the LED (green) does not light up, replace the garage door
opener.

I03244

2104Author!: Date!:

BE–242

–BODY ELECTRICAL GARAGE DOOR OPENER SYSTEM

Wire Harness Side

3. INSPECT GARAGE DOOR OPENER CIRCUIT

Disconnect the connector from the switch and inspect the con­nector on the wire harness side, as shown.

I03432

Te s te r c o nn e c t i on Condition Specified condition

5 – Ground Constant Continuity

4 – Ground Constant Battery positive voltage

2000 LEXUS LS400 (RM717U)

2105Author!: Date!:

BE–240

I03419

–

BE0D4–01

REMOVAL

1. REMOVE FRONT PERSONAL LIGHT LENS

2. REMOVE FRONT PERSONAL LIGHT

(a) Remove the 3 screws.
(b) Disconnect the 2 connectors.

3. REMOVE GARAGE DOOR OPENER

(a) Remove the 3 screws.
(b) Remove the garage door opener connector from the per-

sonal light.

(c) Disconnect the secondary locking device.
(d) Release the locking plug of the terminal 4 and 5, and pull

the terminals out from the rear.

HINT:
Use a small screw driver.

2103Author!: Date!:

LOCATION

BE–239

–

BE0D3–01

Garage Door Opener

I03403

2102Author!: Date!:

BE–236

–BODY ELECTRICAL GARAGE DOOR OPENER SYSTEM

GARAGE DOOR OPENER SYSTEM

BE0D2–01

REGISTRATION PROCEDURE

1. NEW CODE REGISTRATION

NOTICE:

! If pressing the switch of the original transmitter to

register the code, the system might operate.

! When registering the transmitter codes such as for

garage or gate, check that there is nobody around
those places then register.

(a) Press the switch for the item to be registered for 20 se-

conds

HINT:
When transferring to registration mode, LED (red) blinks in 1 Hz
cycle.

(b) In the condition of (a), bring the original transmitter to with-

in 1–inch area around the garage door opener and press
the switch. (code transmitting).

HINT:
When code registration completes correctly, LED (red) blinks in

5.6 Hz cycle.

I03243

2000 LEXUS LS400 (RM717U)

2099Author!: Date!:

–BODY ELECTRICAL GARAGE DOOR OPENER SYSTEM

New code registration timing chart

BE–237

GARAGE DOOR
OPENER SWITCH

LEARN MODE

LED
OPERATION

ORIGINAL
TRANSMITTER

PRESSED

RELEASE

ENTER

EXIT

ON

OFF

ON

OFF

20 sec

LED flashes
at a rate of 1 Hz

LED flashes at a
rate of 5.6 Hz

I03487

If a code can not be registered, observe the following condi­tions.
HINT:

! If the battery of original transmitter is consumed.
! Press the switch of the transmitter repeatedly in registra-

tion mode, as some transmitters stop transmitting for 1 to
2 seconds.

! This system is not applicable to the garage door opener

which had been made before 1982.

2. CODE DELETION

(a) Press the switches at both ends of garage door opener

simultaneously for 20 seconds.

HINT:
When transferring to deletion mode, LED (red) blinks in 6 Hz
cycle.
(b) When releasing the switch within 10 seconds after trans-

ferring to deletion mode, all the registered codes will be
erased.

HINT:
Press the switch until blinking in 6 Hz cycle stops, so that the
default code for check is set.

2000 LEXUS LS400 (RM717U)

2100Author!: Date!:

BE–238

–BODY ELECTRICAL GARAGE DOOR OPENER SYSTEM

Code deletion timing chart

GARAGE DOOR
OPENER SWITCH
(Switch at both end)

CLEAR/DEFAULT
MODE

LED
OPERATION

PRESSED

RELEASE

ON

OFF

ON

OFF

Enter erase mode to erase all 3 channels

20 SEC

10 SEC

LED flashes at a rate of 6 HZ

LOAD DEFAULT

I03488

2000 LEXUS LS400 (RM717U)

2101Author!: Date!:

BE–234

–BODY ELECTRICAL CLOCK

1. PROBLEM No.1

1 CLOCK WILL NOT OPERATE

+B

e–6–1

GND

ACC

IG

I03486

CLOCK

BE0D1–02

TROUBLESHOOTING

HINT:

Problem No.

Clock will not operate 1

Clock loses or gains time 2

± 1.5 seconds / da

(a) Turn the ignition switch ON.
(b) Check that the battery positive voltage is 10 – 16 V.
If voltage is not as specified, replace the battery.
(c) Check that the DOME FR, GAUGE and FR CIG fuses in

not below.

If the fuse is blown, replace the fuse and check for short.
(d) Troubleshoot the clock as follows.
HINT:
Inspect the connector on the wire harness side.

Is there battery positive voltage between terminal
+B and body ground?

Yes

Is there battery positive voltage between terminal
IG and body ground?

Yes

Is there battery positive voltage between terminal
ACC and body ground?

Yes

Is there continuity battery terminal GND and body
ground?

Yes

Is there battery positive voltage between terminal
ILL and body ground when rheostat knob is turned
to any position except fully clockwise? (Taillight
switch ON)

Yes

No

No

No

No

No

Open or short circuit in wire harness between
terminal +B and DOME fuse.

Open or short circuit in wire harness between
terminal IG and GAUGE fuse.

Open or short circuit in wire harness between
terminal ACC and FR CIG fuse.

Open circuit in wire harness between terminal
GND and body ground.

Rheostat light control or wire harness faulty.

Replace clock assembly.

2000 LEXUS LS400 (RM717U)

2097Author!: Date!:

2. PROBLEM No.2

2 CLOCK LOSES OR GAINS TIME

IG

+B

e–6–1

GND

ACC

I03486

BE–235

–BODY ELECTRICAL CLOCK

(a) Check that the battery positive voltage is 10 – 16 V.
If voltage is not as specified, replace the battery.
(b) Inspect the error of the clock.

Allowable error (per day): ± 2.0 seconds

If the error exceeds the allowable error, replace the clock as­sembly.
(c) Check if the clock adjusting button is sticking in position

and has failed to return.

(d) Troubleshoot the clock as follows.
HINT:
Inspect the connector on the wire harness side.

Is there 10 – 16 V between terminal +B and body
ground?

Yes

Is there 10 – 16 V between terminal IG and body
ground?

Yes

Is there 10 – 16 V between terminal ACC and body
ground?

Yes

Adjust or replace clock assembly.

Bellow 10 V

Bellow 10 V

Bellow 10 V

Locate cause and repair, or recharge battery.

Locate cause and repair, or recharge battery.

Locate cause and repair, or recharge battery.

2000 LEXUS LS400 (RM717U)

2098Author!: Date!:

Antenna Nut

Twist

BE4671

BE5781

BE5780

BE4674

BE–233

–

BE11Z–01

REPLACEMENT

1. Auto Antenna Models:
REMOVE ANTENNA ROD

HINT:
Do this operation with the battery negative (–) cable connected
to the battery terminal.
(a) Turn the ignition switch to ”LOCK” position.
(b) Remove the antenna nut.

(c) Press the ”AM, FM” buttons on the radio receiver, and si-

multaneously turn the ignition switch to ”ACC” position.

HINT:

! The rod will extend fully and be released form the motor

antenna.

! After removing the antenna rod, leave the ignition switch

as ”ACC”.

NOTICE:
To prevent body damage when the antenna rod is released,
hold the rod while it comes out.

2. IAuto Antenna Models:
NSTALL ANTENNA ROD

(a) Insert the cable of the rod until it reaches the bottom.
HINT:

! When inserting the cable, the teeth on the cable must face

toward the rear of the vehicle.

! Insert the antenna approx. 300 mm (11.8 in.).

(b) Wind the cable to retract the rod by turning the ignition

switch to ”LOCK” position.

HINT:

! If the ignition switch is already in ”LOCK” position, do step

1 (c) first, then turn the ignition switch to ”ACC” position.

! In case the cable is not wound, twist it, as shown in the

illustration.

! Even if the rod has not retracted fully, install the antenna

nut and inspect the antenna rod operation. It will finally re­tract fully.

(c) Inspect the antenna rod operation by pushing the radio

wave band select buttons.

2096Author!: Date!:

BE–232

–

BE11Y–01

INSPECTION

1. Auto Antenna Models:
INSPECT ANTENNA MOTOR

(a) Connect the positive (+) lead from the battery to terminal

2 and the negative (–) lead to terminal 5.

(b) Check that the motor turns (moves upward).

25

I05587

25

I05580

NOTICE:
These tests must be done quickly (within 3 – 5 seconds) to
prevent the coil from burning out.

(c) Then, reverse the polarity, check that the motor turns the

opposite way (moves downward).

NOTICE:
These tests must be done quickly (within 3 – 5 seconds) to
prevent the coil from burning out.

Wire Harness Side

213

45 768

Te s te r c o nn e c t i on Condition Specified condition

7 – Ground Constant Continuity

1 – Ground

1 – Ground

2 – Ground

2 – Ground

3 – Ground Constant Battery voltage

5 – Ground

5 – Ground

2. Auto Antenna Models:
INSPECT ANTENNA MOTOR CONTROL RELAY CIR­CUIT

Disconnect the connector from the relay and inspect the con­nector on wire harness side, as shown in the chart below.

Z08688

Ignition switch ACC or ON,

and radio switch ON and Others

Ignition switch ACC or ON,

and radio switch ON and AM

Ignition switch ACC or ON,

and radio or tape or CD switch OFF

Ignition switch ACC or ON,

and radio or tape or CD switch ON

Ignition switch ACC or ON,

and radio switch OFF

Ignition switch ACC or ON,

and radio switch ON

No voltage

Battery voltage

No voltage

Battery voltage

No voltage

Battery voltage

2095Author!: Date!:

ANTENNA

LOCATION

BE–231

–

BE11X–01

B

View ”A”

C

A

D

View ”B”

Antenna

View ”C”

View ”D”

I10507

2094Author!: Date!:

BE–226

Wire Harness Side

Connector ”A”

Connector ”B” Connector ”C”

Te s te r c o nn e c t i on Condition Specified condition

B14 – Ground Constant Continuity

B6 – Ground Ignition switch position ACC or ON Battery positive voltage

B6 – Ground Ignition switch position LOCK No voltage

B1 – Ground Constant Battery positive voltage

–BODY ELECTRICAL AUDIO SYSTEM

BE0D0–01

INSPECTION

1. Nakamichi made:
INSPECT RADIO RECEIVER ASSEMBLY CIRCUIT

Disconnect the connectors from the radio receiver assembly.
And inspect the connector on the wire harness side, as shown.

Z14756

If circuit is not as specified, inspect the circuits connected to oth­er parts.
HINT:
Check the wire harness between radio receiver assembly and
the CD auto changer, between radio receiver assembly and
power amplifier.

Wire Harness Side

Connector ”A” Connector ”B”

Connector ”C”

e–9–1 e–13–1–A

eh–14–1 h–14–1–A

2000 LEXUS LS400 (RM717U)

Connector ”D”

2. Nakamichi made:
INSPECT POWER AMPLIFIER CIRCUIT

Disconnect the connector from the power amplifier and inspect
the connector on the wire harness side, as shown.

Z14757

2089Author!: Date!:

–BODY ELECTRICAL AUDIO SYSTEM

Te s te r c o nn e c t i on Condition Specified condition

A4 – Ground Constant Continuity

A5 – Ground Constant Battery positive voltage

A6 – Ground Ignition switch position ACC or ON Battery positive voltage

D6 – Ground

Ignition switch position ACC or ON

Radio, Tape or CD switch ON

Battery positive voltage

If circuit is not as specified, inspect the circuits connected to oth­er parts.

BE–227

Wire Harness Side

h–14–1–A

Te s te r c on n e c t i on t o

terminal number

5 – Ground Constant Battery positive voltage

4 – Ground Ignition switch LOCK No voltage

4 – Ground Ignition switch ACC or ON Battery positive voltage

3. Nakamichi made:
INSPECT CD AUTO CHANGER CIRCUIT

Disconnect the connectors from the controller and inspect the
connector on the wire harness side, as shown.

Z14758

Condition Specified condition

If circuit is not as specified, inspect the circuits connected to oth­er parts.
HINT:
Since the signals to and from the AP+, AP–, SGND, GND1 ter­minals are serial signals, they cannot ordinarily be measured
with a tester.

2000 LEXUS LS400 (RM717U)

2090Author!: Date!:

BE–228

–BODY ELECTRICAL AUDIO SYSTEM

Wire Harness Side

Connector ”A”

Connector ”B”

Te s te r c o nn e c t i on Condition Specified condition

B1 – Ground Constant Continuity

A6 – Ground Ignition switch position ACC or ON Battery positive voltage

A6 – Ground Ignition switch position LOCK No voltage

A1 – Ground Constant Battery positive voltage

4. Pioneer made:
INSPECT RADIO RECEIVER ASSEMBLY CIRCUIT

Disconnect the connectors from the radio receiver assembly.
And inspect the connector on the wire harness side, as shown.

I03482

If circuit is not as specified, inspect the circuits connected to oth­er parts.
HINT:
Check the wire harness between power amplifier and the CD
auto changer, between radio receiver assembly and power am­plifier.

Wire Harness Side

Connector ”A”

Connector ”C”

Connector ”E”

2000 LEXUS LS400 (RM717U)

Connector ”B”

Connector ”D”

5. Pioneer made and LEXUS navigation system:
INSPECT POWER AMPLIFIER CIRCUIT

Disconnect the connector from the power amplifier and inspect
the connector on the wire harness side, as shown.

I03483

2091Author!: Date!:

–BODY ELECTRICAL AUDIO SYSTEM

Te s te r c o nn e c t i on Condition Specified condition

B7 – Ground Constant Continuity

B4 – Ground Constant Battery positive voltage

C12 – Ground Ignition switch position ACC or ON Battery positive voltage

If circuit is not as specified, inspect the circuits connected to oth­er parts.

BE–229

Wire Harness Side

Te s te r c on n e c t i on t o

terminal number

5 – Ground Constant Battery positive voltage

12 – Ground Ignition switch LOCK No voltage

12 – Ground Ignition switch ACC or ON Battery positive voltage

6. Pioneer made and LEXUS navigation system:
INSPECT CD AUTO CHANGER CIRCUIT

Disconnect the connectors from the controller and inspect the
connector on the wire harness side, as shown.

I03484

Condition Specified condition

If circuit is not as specified, inspect the circuits connected to oth­er parts.
HINT:
Since the signals to and from the AP+, AP–, SGND, GND1 ter­minals are serial signals, they cannot ordinarily be measured
with a tester.

2000 LEXUS LS400 (RM717U)

2092Author!: Date!:

BE–230

–BODY ELECTRICAL AUDIO SYSTEM

Wire Harness Side

Connector ”A”

Connector ”B” Connector ”C”

Te s te r c o nn e c t i on Condition Specified condition

B2 – Ground Constant Continuity

B1 – Ground Ignition switch position ACC or ON Battery positive voltage

B1 – Ground Ignition switch position LOCK No voltage

B4 – Ground Constant Battery positive voltage

7. LEXUS navigation system:
INSPECT RADIO RECEIVER ASSEMBLY CIRCUIT

Disconnect the connectors from the radio receiver assembly.
And inspect the connector on the wire harness side, as shown.

I03485

If circuit is not as specified, inspect the circuits connected to oth­er parts.
HINT:
Check the wire harness between power amplifier and the CD
auto changer, between radio receiver assembly and power am­plifier.

8. INSPECT GLASS PRINTED ANTENNA

(Use same procedure as for ”INSPECT DEFOGGER WIRES”
on page BE–116)

9. REPAIR GLASS PRINTED ANTENNA

(Use same procedure as for ”REPAIR DEFOGGER WIRES” on
page BE–116)

2000 LEXUS LS400 (RM717U)

2093Author!: Date!:

LOCATION

BE–225

–

BE0CZ–01

Engine Room Junction Block

! DOME Fuse
! RADIO No.1 Fuse

Tweeter
Speaker

Ignition Switch

Tweeter Speaker

Instrument Panel
Junction Block
! RADIO No.2 Fuse

Power Amplifier

Front Door Speaker

Rear Door Speaker

CD Auto
Changer

Radio Receiver
Assembly

Front Door Speaker

Rear Door Speaker

Woofer Speaker

I03405

2088Author!: Date!:

BE–207

–BODY ELECTRICAL AUDIO SYSTEM

BE0CY–01

TROUBLESHOOTING

NOTICE:
When replacing the internal mechanism (computer part) of the audio system, be careful that no part
of your body or clothing comes in contact with the terminals of the leads from the IC, etc. of the re­placement part (spare part).

HINT:
This inspection procedure is a simple troubleshooting which should be carried out on the vehicle during sys­tem operation and was prepared on the assumption of system component troubles (except for the wires and
connectors, etc.).
Always inspect the trouble taking the following items into consideration.

! Open or short circuit of the wire harness
! Connector or terminal connection fault

Problem No.

Radio No power coming in. 1

Power coming in, but radio not operating. 2

Noise present, but AM – FM not operating. 3

Either speaker does not work. 4

Either AM or FM does not work. 5

Reception poor (Volume faint). 5

Few preset tuning bands. 5

Sound quality poor. 6

Cannot set station select button. 7

Preset memory disappears. 7

Ta p e P l a y er Cassette tape cannot be inserted. 8

Cassette tape inserts, but no power. 9

Power coming in, but tape player not operating. 10

Either speaker does not work. 11

Sound quality poor (Volume faint). 12

Ta p e j a m me d , m al f u n ct i o n wi t h ta p e s pe e d or a u to – r e v er s e . 13

Cassette tape will not eject. 14

CD Player CD cannot be inserted. 15

CD inserts, but no power. 16

Power coming in, but CD player not operating. 17

Sound jumps. 18

Sound quality poor (Volume faint). 19

Either speaker does not work. 20

CD will not eject. 21

Amplifier No power coming in. 22

Either speaker does not work. 23

Noise Noise produced by vibration or shock while driving. 24

Noise produced when engine starts. 25

Noise occurs 26

2000 LEXUS LS400 (RM717U)

2070Author!: Date!:

BE–208

1

Radio NO POWER COMING IN

–BODY ELECTRICAL AUDIO SYSTEM

Is tape player operating normally?

Yes

Radio receiver assembly faulty.

No

No

Check if RADIO No.2 fuse is OK.

Replace fuse.

Yes

Is ACC applied to radio receiver assembly?

No

ACC wire harness faulty.

Yes

Check if DOME fuse is OK?

No

Replace fuse.

Yes

Is +B applied to radio receiver assembly?

No

+B wire harness faulty.

Yes

Check if GND (wire harness side) to radio is

No

GND faulty.

OK?

Yes

Radio receiver assembly faulty.

2 Radio POWER COMING IN, BUT RADIO NOT OPERATING

If radio side faulty

Is tape player operating normally?

Yes

Go to No. 23.

No

Is there continuity in speaker wire harness?

No

Speaker wire harness faulty.

Yes

Te mp or ar il y i ns ta ll a no the r sp ea ke r.
Function OK?

Yes

speaker faulty.

No

Radio receiver assembly faulty.

3 Radio NOISE PRESENT, BUT AM–FM NOT OPERATING

Go to No. 23

Radio receiver assembly faulty.

If radio side faulty

Radio receiver
assembly faulty.

V06272

2000 LEXUS LS400 (RM717U)

2071Author!: Date!:

–BODY ELECTRICAL AUDIO SYSTEM

4 Radio EITHER SPEAKER DOES NOT WORK

BE–209

Is tape player operating normally?

No

Is hiss produced by non–functioning speaker?

No

Check if GND to power amplifier is OK?

Yes

Are +B and +B2 applied to power amplifier?

Yes

Is AMP applied to power amplifier?

Yes

Is there continuity in wire harness? (Radio receiver
to power amplifier)

Yes

Is there continuity in speaker wire harness?

Yes

Te mp or ar il y i ns ta ll a no the r sp ea ke r.
Functions OK?

Yes

Yes

No

No

No

No

No

Yes

Radio receiver assembly faulty.

Radio receiver assembly faulty.

GND fault.

+B and +B2 wire harness faulty.

Check the radio receiver assembly.

Wire harness faulty.

Speaker wire harness faulty.

Speaker faulty.

No

Radio receiver assembly faulty.

2000 LEXUS LS400 (RM717U)

V06273

2072Author!: Date!:

BE–210

–BODY ELECTRICAL AUDIO SYSTEM

5 Radio

FEW PRESET TUNING BANDS

Problem with radio wave signals or location?
(See page BE–203)

No

Are both AM and FM defective?

Yes

Go to No.28

If radio side faulty

Is tape player operating normally?

No

Temporarily install another speaker. Functions
OK?

No

Radio receiver assembly faulty.

EITHER AM OR FM DOES NOT WORK, RECEPTION POOR (VOLUME FAINT),

Yes

No

Yes

Yes

Poor signals, poor location.

Radio receiver assembly faulty.

Radio receiver assembly faulty.

Speaker faulty.

6

Radio SOUND QUALITY POOR

Is sound quality always bad?

Yes

Is tape player operating normally?

No

Is speaker properly installed?

Yes

Temporarily install another speaker. Functions
OK?

6–A.

Is sound quality bad in certain areas only?

No

No

Yes

No

Yes

No

Yes

Go to step 6–A.

If radio side faulty

Go to No.28.

Radio receiver
assembly faulty.

Install properly.

Speaker faulty.

Radio receiver assembly faulty.

Poor signals, poor location.

Radio receiver assembly faulty.

2000 LEXUS LS400 (RM717U)

V03663

2073Author!: Date!:

BE–211

–BODY ELECTRICAL AUDIO SYSTEM

7 Radio CANNOT SET STATION SELECT BUTTON, PRESET MEMORY DISAPPEARS

Can cassette tape be inserted in tape player?

Yes

Radio receiver assembly faulty.

No

No

Check if DOME and RADIO No.2 fuses are OK.

Replace fuse.

Yes

Are ACC and +B applied to radio receiver assem-

No

ACC and +B wire harness faulty.

bly?

Yes

Check if GND (wire harness side) to radio is OK.

No

GND faulty.

Yes

Radio receiver assembly faulty.

8 Tape Player CASSETTE TAPE CANNOT BE INSERTED

Is there a foreign object inside tape player? Remove foreign object.

Yes

No

Is auto search button of radio operating normally?

No

Check if DOME and RADIO No.2 fuses are OK.

Yes

Are ACC and +B applied to radio receiver assem­bly?

No

ACC and +B wire harness faulty.

Yes

No

Yes

Radio receiver assembly faulty.

Replace fuse.

Check if GND (wire harness side) to radio receiver
assembly is OK?

No Yes

GND faulty.

Radio receiver
assembly faulty.

2000 LEXUS LS400 (RM717U)

V06275

2074Author!: Date!:

BE–212

–BODY ELECTRICAL AUDIO SYSTEM

9 CASSETTE TAPE INSERTS, BUT NO POWER

Tape Player

Is tape operating normally?

No

Check if DOME and RADIO No.2 fuses are OK.

Yes

Is ACC applied to radio receiver assembly?

No

ACC wire harness faulty.

10 POWER COMING IN, BUT TAPE PLAYER NOT OPERATINGTape Player

Functions OK if different cassette tape inserted?

No

Is radio operating normally?

Yes

No

Yes

Yes

Yes

Radio receiver assembly faulty.

Replace fuse.

Radio receiver assembly faulty.

Cassette tape faulty.

Radio receiver assembly faulty.

No

Is there continuity in speaker wire harness?

Yes

Te mp or ar il y i ns ta ll a no the r sp ea ke r.
Functions OK?

No

Radio receiver assembly faulty.

No

Yes

Speaker wire harness faulty.

Speaker faulty.

2000 LEXUS LS400 (RM717U)

V06276

2075Author!: Date!:

–BODY ELECTRICAL AUDIO SYSTEM

BE–213

11

Tape Player

EITHER SPEAKER DOES NOT WORK

Check if RADIO No.1 and RADIO No.2 fuses are
OK.

Yes

Is radio operating normally?

No

Check if GND to power amplifier is OK.

Yes

Are +B and +B2 applied to power amplifier?

Yes

Is AMP applied to power amplifier?

Yes

Is there continuity in wire harness? (Radio receiver
to power amplifier)

Yes

Temporarily install another woofer speaker.
Functions OK?

No

Yes

No

No

No

No

Yes

Replace fuse.

Radio receiver assembly faulty.

GND faulty.

+B and +B2 wire harness faulty.

Check the radio receiver assembly.

Wire harness faulty.

Woofer speaker faulty.

No

Is there continuity in speaker wire harness?

Yes

Te mp or ar il y i ns ta ll a no the r po we r am pli fi er.
Functions OK?

Yes

Power amplifier faulty.

No

No

Speaker wire harness faulty.

Radio receiver assembly faulty.

2000 LEXUS LS400 (RM717U)

V06277

2076Author!: Date!:

BE–214

–BODY ELECTRICAL AUDIO SYSTEM

Tape Player

SOUND QUALITY POOR (VOLUME FAINT)12

Functions OK if different cassette tape inserted?

No

Operates normally after cleaning the heads?
(See page BE–203)

No

Is radio operating normally?

No

Is speaker properly installed?

Yes

Te mp or ar il y i ns ta ll a no the r sp ea ke r.
Functions OK?

No

Radio receiver assembly faulty.

Yes

Yes

Yes

No

Yes

Cassette tape faulty.

Head dirty.

Radio receiver assembly faulty.

Install properly.

Speaker faulty.

TAPE JAMMED, MALFUNCTION WITH TAPE SPEED OR AUTO–REVERSETape Player13

Functions OK if different tape (less than 120 mins.)
is inserted?

No

Is there a foreign object inside tape player?

No

Operates normally after cleaning the heads?
(See page BE–203)

No

Radio receiver assembly faulty.

Yes

Yes

Yes

Cassette tape faulty.

Remove foreign object.

Head dirty.

2000 LEXUS LS400 (RM717U)

V03671

2077Author!: Date!:

–BODY ELECTRICAL AUDIO SYSTEM

BE–215

14 Tape Player

Is tape player operating normally?

CASSETTE TAPE WILL NOT EJECT

No

Cassette tape jammed.

Yes

Is auto search button of radio operating normally?

Yes

Radio receiver assembly faulty.

No

Check if DOME fuse is OK? Replace fuse.

No

Yes

Is +B applied to radio receiver assembly?

Yes

Radio receiver assembly faulty.

No

+B wire harness faulty.

CD CANNOT BE INSERTED15 CD Player

Yes

Is CD already inserted?

Eject CD.

No

Is 3.2 in. (8 cm) disc being used?

No

Is auto search button of radio operating normally?

Yes

Is +B applied to CD auto changer?

Yes

Is ACC applied to CD auto changer?

Yes

Check if GND (wire harness side) to CD auto
changer is OK?

Yes

Is there continuity in CD auto changer wire har­ness? (to radio receiver assembly)

Yes

Temporarily install another CD auto changer.
Functions OK?

Yes

No

No

No

No

No

No

Use 4.7 in. (12 cm) disc.

Check if RADIO No.1 and
RADIO No.2 fuses are OK?

No

Replace
fuse.

Yes

+B wire harness faulty.

ACC wire harness faulty.

GND wire harness faulty.

Wire harness faulty. (to radio receiver assembly)

Radio receiver assembly faulty.

Yes

CD auto changer faulty.

2000 LEXUS LS400 (RM717U)

V06279

2078Author!: Date!:

BE–216

–BODY ELECTRICAL AUDIO SYSTEM

CD INSERTS, BUT NO POWER16 CD Player

Is radio operating normally?

Yes

Is +B applied to CD auto changer?

Yes

Is ACC applied to CD auto changer?

Yes

Check if GND (wire harness side) to CD auto
changer is OK.

Yes

Is there continuity in CD auto changer wire har­ness? (to radio receiver assembly)

Yes

Temporarily install another CD auto changer.
Functions OK?

Check if RADIO No.1 and RADIO No.2 fuses are

No

OK?

NoYes

Replace fuse.

No

+B wire harness faulty.

No

ACC wire harness faulty.

GND wire harness faulty.

No

Wire harness faulty. (to radio receiver assembly)

No

No

Radio receiver assembly faulty.

Yes

CD auto changer faulty.

2000 LEXUS LS400 (RM717U)

V06280

2079Author!: Date!:

–BODY ELECTRICAL AUDIO SYSTEM

BE–217

17

CD Player

POWER COMING IN, BUT PLAYER NOT OPERATING

Is CD inserted correct side up?

Yes

Is 3.2 in. (8 cm) disc being used?

No

Functions OK if different CD inserted?

No

Is radio operating normally?

Yes

Is temperature inside luggage compartment hot?

No

Does sudden temperature changer occur inside
luggage compartment?

No

No

Yes

Yes

No

Yes

Yes

Insert correctly.

Use 4.7 in. (12 cm) disc.

CD faulty.

Go to step 17–B.

Protective circuit in operation.

Formation of condensation due to temp.
change.

Go to step 17–A.

17–A.

Is +B applied to CD changer?

Yes

Is ACC applied to CD auto changer?

Yes

Check if GND (wire harness side) to CD auto
changer is OK?

Yes

Is there continuity in CD auto changer wire har­ness? (to radio receiver assembly)

Yes

Temporarily install another CD auto changer.
Functions OK?

Yes

CD auto changer faulty.

No

+B wire harness faulty.

No

ACC wire harness faulty.

GND wire harness faulty.

No

Wire harness faulty. (to radio receiver assembly)

No

Radio receiver assembly faulty.

No

2000 LEXUS LS400 (RM717U)

V06281

2080Author!: Date!:

BE–218

17–B.

Is there continuity in speaker wire harness?

Yes

–BODY ELECTRICAL AUDIO SYSTEM

No

Speaker wire harness faulty.

Te mp or ar il y i ns ta ll a no the r sp ea ke r.
Functions OK?

Yes

Go to step 17–A.

SOUND JUMPS18 CD Player

Does sound jump only during strong vibration?

No

Is CD auto changer properly installed?

Yes

Functions OK if different CD inserted?

No

Does sudden temperature changer occur in lug­gage compartment?

Yes

Yes

No

Yes

Yes

speaker faulty.

Jumping caused by vibration.

Install properly.

CD faulty.

Formation of condensation due to temp.
change.

No

Is +B applied to CD auto changer?

Yes

Is ACC applied to CD auto changer?

Yes

Check if GND (wire harness side) to CD auto
changer is OK?

Yes

Is there continuity in CD auto changer wire har­ness? (to radio receiver assembly)

Yes

Temporarily install another CD auto changer.
Functions OK?

Yes

CD auto changer faulty.

No

+B wire harness faulty.

No

ACC wire harness faulty.

GND wire harness faulty.

No

Wire harness faulty. (to radio receiver assembly)

No

Radio receiver assembly faulty.

No

2000 LEXUS LS400 (RM717U)

V06282

2081Author!: Date!:

BE–219

–BODY ELECTRICAL AUDIO SYSTEM

SOUND QUALITY POOR (VOLUME FAINT)19 CD Player

Functions OK if different CD inserted?

No

Is radio operating normally?

No

Is speaker properly installed.

Yes

Temporarily install another speaker. Functions
OK?

No

Is +B applied to CD auto changer?

Yes

Is ACC applied to CD auto changer?

Yes

Check if GND (wire harness side) to CD auto
changer is OK?

Yes

Yes

No

Yes

No

No

No

CD faulty.

Install properly

Speaker faulty.

+B wire harness faulty.

ACC wire harness faulty.

GND wire harness faulty.

Yes

Is there continuity in CD auto changer wire har­ness? (to radio receiver assembly)

Yes

Temporarily install another CD auto changer.
Functions OK?

Yes

CD auto changer faulty.

Wire harness faulty.

No

(to radio receiver assembly)

Radio receiver assembly faulty.

No

2000 LEXUS LS400 (RM717U)

V03678

2082Author!: Date!:

BE–220

–BODY ELECTRICAL AUDIO SYSTEM

EITHER SPEAKER DOES NOT WORK20 CD Player

Is radio operating normally? Go to step 20–A.

Yes

No

Yes

Is power amplifier operating normally?

Go to step 20–A.

No

Yes

Is hiss produced by non–functioning speaker?

Go to step 20–A.

No

Is there continuity in speaker wire harness?

No

Speaker wire harness faulty.

Yes

Te mp or ar il y i ns ta ll a no the r sp ea ke r.

Yes

Speaker faulty.

Functions OK?

No

Go to step 20–A.

20–A

Is +B applied to CD auto changer? +B wire harness faulty.

No

Yes

Is ACC applied to CD auto changer?

No

ACC wire harness faulty.

Yes

Check if GND (wire harness side) to CD auto
changer is OK?

Yes

Is there continuity in CD auto changer wire har­ness? (to radio receiver assembly)

Yes

Te mp or ar il y i ns ta ll a no the r CD a ut o cha ng er ?
Functions OK?

Yes

CD auto changer faulty.

GND wire harness faulty.

No

Wire harness faulty. (to radio receiver assembly)

No

Radio receiver assembly faulty.

No

2000 LEXUS LS400 (RM717U)

V06283

2083Author!: Date!:

–BODY ELECTRICAL AUDIO SYSTEM

BE–221

CD Player

CD WILL NOT EJECT21

Is auto search button of radio operating normally?

Yes

Is +B applied to CD auto changer?

Yes

Is ACC applied to CD auto changer?

Yes

Check if GND (wire harness side) to CD auto
changer is OK?

Yes

Is there continuity in CD auto changer wire har­ness? (to radio receiver assembly)

Yes

Check if RADIO No.1 and RADIO No.2 fuses are

No

OK?

Yes

No

Replace fuse.

No

+B wire harness faulty.

No

ACC wire harness faulty.

GND wire harness faulty.

No

Wire harness faulty. (to radio receiver assembly)

No

Temporarily install another CD auto changer.
Functions OK?

Yes

CD auto changer faulty.

Amplifier

NO POWER COMING IN22

Are +B and +B2 applied to power amplifier?

Yes

AMP fuse is OK?

Yes

Is ACC applied to power amplifier?

Yes

Is there continuity in wire harness? (Radio receiver
to power amplifier)

Yes

Check if GND to body is OK.

Radio receiver assembly faulty.

No

No

No

No

No

No

Power amplifier faulty.

Replace fuse.

Power amplifier.

Wire harness faulty.

GND faulty.

Yes

Radio receiver assembly faulty.

2000 LEXUS LS400 (RM717U)

V06285

2084Author!: Date!:

BE–222

–BODY ELECTRICAL AUDIO SYSTEM

EITHER SPEAKER DOES NOT WORK23 Amplifier

Is power amplifier operating normally?

No

Is hiss produced by non–functioning speaker?

No

Is there continuity in speaker wire harness?

Yes

Te mp or ar il y i ns ta ll a no the r sp ea ke r.
Functions OK?

No

Power amplifier faulty.

NOISE PRODUCED BY VIBRATION OR SHOCK WHILE DRIVING24 Noise

Is speaker properly installed?

Yes

Yes

No

Yes

No

Radio receiver assembly faulty.

Radio receiver assembly faulty.

Speaker wire harness faulty.

Speaker faulty.

Install properly.

Yes

No

Is each system correctly installed?

Install properly.

Yes

With vehicle stopped, lightly tap each system.

Yes

Each system faulty.

Is noise produced?

No

Noise produced by static electricity accumulating in the vehicle body.

2000 LEXUS LS400 (RM717U)

V06286

2085Author!: Date!:

BE–223

–BODY ELECTRICAL AUDIO SYSTEM

NOISE PRODUCED WHEN ENGINE STARTS25 Noise

Whistling noise which becomes high– pitched when
accelerator strongly depressed, disappears shortly
after engine stops.

No

Whining noise occurs when A/C is operation.

No

Scratching noise occurs during sudden accelera­tion, driving on rough roads or when ignition switch
is turned on.

No

Clicking sound heard when horn button is pressed,
then released. Whirring/grating sound when
pushed continuously.

No

Murmuring sound, stops when engine stops.

No

Tick–tock noise, occurs in co–ordination with blink­ing of flasher.

No

Alternator noise.

Yes

Yes

Yes

Yes

A/C noise.

Fuel gauge noise.

Horn noise.

Yes

Ignition noise.

Yes

Turn signal noise.

Noise occurs during window washer operation.

No

Scratching noise occurs while engine is running
and continues a while even after engine stops.

No

Scraping noise in time wiper beat.

No

Other type of noise.

Yes

Yes

Yes

Washer noise.

Engine coolant temp. gauge noise.

Wiper noise.

2000 LEXUS LS400 (RM717U)

V06356

2086Author!: Date!:

BE–224

26 Noise NOISE OCCURS

–BODY ELECTRICAL AUDIO SYSTEM

Does the noise occur only in the radio?

Yes

Does the noise occur in a particular place?

No

Is there any additional installation part
around the glass imprinted antenna?
(Sun shade film, telephone antenna etc.)

No

Does the noise occur even pulling out the
antenna cord from the radio?

No

Does the noise occur even pulling out the
antenna terminal on the glass surface?

No

Isn’t there any adhesive (Butyl rubber)
stuck on the bases of the antenna
terminal, defogger terminal and bus bar?

No

(It occurs in the cassette
and CD.)

Yes

Yes

An electric environment.

Does the noise stop by removing it?

Yes

Influence of the film or the noise radiation
of the additional installation part.

Yes

Yes

Yes

Check the radio.

Mixing into the antenna cable.

Failure of glass installation.
Muse plane the butyl rubber.

Refer to No.25.

No

Does the noise occur even pulling out
the defogger terminal?

No

Check the grounding of the antenna,
antenna cord, coke coil, and noise filter.
(See page BE–203)

OK

Does the condition get better by exchanging
the choke coil?

No

Does the condition get better by exchanging
the antenna cord.

No

Radiate directly to the antenna from the
generation source.

Yes

NG

Yes

Yes

Interfering noise from the defogger line
and choke coil.

Grounding failure.

Exchange the choke coil.

Exchange the antenna cord.

2000 LEXUS LS400 (RM717U)

V08552

2087Author!: Date!:

BE–202

–BODY ELECTRICAL AUDIO SYSTEM

AUDIO SYSTEM

DESCRIPTION

1. RADIO WAVE BAND

The radio wave bands used in radio broadcasting are as follows:

Frequency

Designation

Radio wave

Modulation method

LF: Low frequency MF: Medium Frequency HF: High Frequency VHF: Very High Frequency

30 kHz

300 kHz

LF

AM FM

Amplitude modulation

2. SERVICE AREA

There are great differences in the size of the service area for AM
and FM monaural. Sometimes FM stereo broadcasts cannot be
received even through AM can be received in very clearly.
Not only does FM stereo have the smallest service area, but it

FM (Stereo)

FM (Monaural)

AM

also picks up static and other types of interference (”noise”)
easily.

3 MHz 30 MHz 300 MHz

MF

HF

BE0CX–03

VHF

Frequency modulation

Fading

Ionosphere

BE2818

3. RECEPTION PROBLEMS

Besides the problem of static, there are also the problems
called ”fading”, ”multipath” and ”fade out”. These problems are
caused not by electrical noise but by the nature of the radio
waves themselves.

(1) Fading

Besides electrical interference, AM broadcasts are
also susceptible to other types of interference, es­pecially at night. This is because AM radio waves
bounce off the ionosphere at night. These radio
waves then interfere with the signals from the same
transmitter that reach the vehicle’s antenna directly.
This type of interference is called ”fading”.

BE2819

2000 LEXUS LS400 (RM717U)

2065Author!: Date!:

–BODY ELECTRICAL AUDIO SYSTEM

BE–203

Multipath

Fade Out

(2) Multipath

One type of interference caused by the bounce of
radio waves off of obstructions is called ”multipath”.
Multipath occurs when a signal from the broadcast
transmitter antenna bounces off buildings and
mountains and interferes with the signal that is re­ceived directly.

BE2820

(3) Fade Out

Because FM radio waves are of higher frequencies
than AM radio waves, they bounce off buildings,
mountains, and other obstructions. For this reason,
FM signals often seem to gradually disappear or
fade away as the vehicle goes behind a building or
other obstruction. This is called ”fade out”.

BE2821

4. NOISE PROBLEMS

(a) Questionnaire for noise:

It is very important for noise troubleshooting to have good
understanding of the claims from the customers, so that
make the best use of following questionnaire and diag­nose the problem accurately.

AM

FM

Noise occurs at a specific place.

Noise occurs when listening to
faint broadcasting.

Noise occurs only at night.

Noise occurs while driving and
at a specific place.

Strong possibility of foreign noise.

There is a case that the same program is broadcasted
from each local station and that may be the case you are
listening different station if the program is the same.

Strong possibility of the beat from a distant broadcasting.

Strong possibility of multipath noise and fading noise
caused by the changes of FM waves.

HINT:
In the case that the noise occurrence condition does not meet
any of the above questionnaire, check based on the ”Trouble
Phenomenon”.
Refer to above descriptions for multipath and fading.

2000 LEXUS LS400 (RM717U)

2066Author!: Date!:

BE–204

–BODY ELECTRICAL AUDIO SYSTEM

(b) Matters that require attention when checking:

! Noise coming into the radio usually has no harm for

practical use as the noise protection is taken and it
is hardly thinkable for an extremely loud noise to
come in. When extremely loud noise comes into the
radio, check if the grounding is normal where the
antenna is installed.

! Check if all the regular noise prevention parts are

properly installed and if there is any installation of
non–authorized parts and non–authorized wiring.

! If you leave the radio under out of tune (not tuning),

it is easy to diagnose the phenomenon as noise oc­curs frequently.

Noise

Noise

to Radio

Battery

Glass Printed Antenna

Noise

Signal

Noise

Noise

Choke Coil

Radio

N21545

(c) Antenna and noise:

Electronic signal received by the antenna will reach to the
radio transmitting through the core wire of the coaxial
cable. Any noise wave other than radio wave is mixed into
this core wire, that naturally causes noise in the radio and
poor sound quality. In order to prevent these noises from
mixing into the radio, the core wire inside the coaxial cable
is covered with a mesh wire called shield wire. This shield
wire shelters the noise and transmits it to the ground, thus
preventing noise from mixing in.

If this shield wire has grounding failure, that causes noise.

(d) Choke coil and noise:

The choke coil is connected in the rear window defogger
circuit. This is connected so to prevent noise from mixing
into the radio by making the noise current included in the
power source of the rear window defogger flow to the
ground.

Noise

2000 LEXUS LS400 (RM717U)

N21546

2067Author!: Date!:

–BODY ELECTRICAL AUDIO SYSTEM

BE–205

Antenna
Ter mi n al

Plug (Main)

1

3 4

Plug (Sub)

(Main)

Antenna
Terminal
(Sub)

I04609

(e) Antenna code continuity check and grounding point:
HINT:
During troubleshooting, in case that the antenna code continu­ity check, grounding check and grounding check of the choke

2

coil are needed, please check referring to the following illustra­tion.

Te r mi n a l c o n ne c t i o n Normal condition

(1) ↔ (2) Continuity

(3) ↔ (4) No continuity

5. COMPACT DISC PLAYER

Compact Disc Players use a laser beam pick–up to read the dig­ital signals recorded on the CD and reproduce analog signals
of the music, etc.
HINT:
Never attempt to disassemble or oil any part of the player unit.
Do not insert any object other than a disc into the magazine.

NOTICE:
CD players use an invisible laser beam which could cause
hazardous radiation exposure. Be sure to operate the play­er correctly as instructed.

Example :

Head

Pinch Roller

2000 LEXUS LS400 (RM717U)

Capstan

N17398

BE4331

6. Tape Player/Head Cleaning:
MAINTENANCE

(a) Raise the cassette door with your finger.

Next, using a pencil or similar object, push in the guide.

(b) Using a cleaning pen or cotton applicator soaked in clean-

er, clean the head surface, pinch rollers and capstans.

7. CD Player/Disc Cleaning:
MAINTENANCE

If the disc gets dirty, clean the disc by wiping the surface from
the center to outside in the radial directions with a soft cloth.

NOTICE:
Do not use a conventional record cleaner or anti–static pre­servative.

2068Author!: Date!:

BE–206

–BODY ELECTRICAL AUDIO SYSTEM

8. OUTLINE OF AVC–LAN

(a) What is AVC–LAN?

AVC–LAN is the abbreviation, which stands for Audio Visual Communication–Local Area Network.
This is a unified standard co–developed by 6 audio manufactures associated with Toyota Motor Corpo­ration.
The Unified standard covers signals, such as audio signal, visual signal, signal for switch indication
and communication signal.

(b) Objectives

Recently the car audio system has been rapidly developed and functions have been changed drasti­cally. The conventional system has been switched to the multi–media type such as a navigation sys­tem. At the same time the level of customers needs to audio system has been heightened. This lies
behind this standardization.
The concrete objectives are explained below.

! When products by different manufactures were combined together, there used to be a case

that malfunction occurred such as sound did not come out. This problem has been resolved
by standardization of signals.

! Various types of after market products have been able to add or replace freely.
! Thanks to the above (2), each manufacture has become able to concentrate on developing

products in their strongest field. This has enabled many types of products provided inex­pensively.

! Conventionally, a new product developed by a manufacture could not be used due to a lack

of compatibility with other manufactures products. Thanks to this new standard, users can

enjoy compatible products provided for them timely.
The above descriptions are the objectives to introduce AVC–LAN. By this standardization, development of
new products will no longer cause systematic errors. Thus, this is very effective standard for a product in the
future.
HINT:

! When +B short or GND short is detected in AVC–LAN circuit, communication stops. Accordingly the

audio system does not function normally.

! When audio system is not equipped with a navigation system, audio head unit is the master unit.
! The car audio system using AVC–LAN circuit has a diagnosis function.
! Each product has its own specified numbers called physical address. Numbers are also allotted to

each function in one product, which are called logical address.

2000 LEXUS LS400 (RM717U)

2069Author!: Date!:

ON

BE–201

–

BE0CW–01

INSPECTION

1. INSPECT FUEL LID OPENER SWITCH CONTINUITY

(a) Check that there is continuity between terminals with the

switch ON (Lever pulled).

(b) Check that there is no continuity between terminals with

the switch OFF (Lever free).

If continuity is not as specified, replace the switch assembly.

N13319

2. INSPECT FUEL LID OPENER SOLENOID OPERATION

(a) Apply battery positive voltage to the terminals.
(b) Check that the solenoid operates in the open direction.
If operation is not as specified, replace the solenoid.

N06769

2064Author!: Date!:

BE–200

FUEL LID OPENER SYSTEM

LOCATION

–

BE0CV–01

Fuel Lid Opener Switch

Instrument Panel Junction Block
! FUEL OPN Fuse

Fuel Lid Opener Solenoid

I03237

2063Author!: Date!:

Z14905

BE–197

–BODY ELECTRICAL SEAT HEATER SYSTEM

BE0CU–01

INSPECTION

1. INSPECT SEAT HEATER SWITCH CONTINUITY

Condition Te s te r c o nn e c t i on Specified condition

OFF – No continuity

ON (Left) 8 – 9 – 11 Continuity

ON (Right) 8 – 11 – 13 Continuity

Illumination 10 – 12 Continuity

If continuity is not as specified, replace the switch or bulb.

2. INSPECT SEAT HEATER SWITCH INDICATOR

(a) Connect the positive (+) lead from the battery to terminal

11 and the negative (–) lead to terminal 8.

(b) Push the switch and check that the indicator light lights

up.

If operation is not as specified, replace the switch.

Wire Harness Side

Te s te r c on n e c t i on t o

terminal number

8 – Ground Constant Continuity

9 – Ground Constant * Continuity

13 – Ground Constant * Continuity

11 – G round Ignition switch turned to ON Battery positive voltage

N13349

3. INSPECT SEAT HEATER SWITCH CIRCUIT

Disconnect the switch connector and inspect the connector on
the wire harness side, as shown.

Z14753

Condition Specified condition

*: There is resistance because this circuit is grounded through
the relay coil.
If circuit is not as specified, inspect the circuits connected to oth­er parts.

2000 LEXUS LS400 (RM717U)

2060Author!: Date!:

BE–198

Z08901

–BODY ELECTRICAL SEAT HEATER SYSTEM

4. INSPECT ENGINE MAIN RELAY CONTINUITY

Condition Te s te r c o nn e c t i on Specified condition

Constant

Apply B+ between

terminals 1 and 3.

1 – 3

2 – 4

4 – 5 Continuity

Continuity

If continuity is not as specified, replace the relay.

5. INSPECT ENGINE MAIN RELAY CIRCUIT

Remove the relay and inspect the connector on the junction
block side, as shown.

BE4730

Te s te r c o nn e c t i on Condition Specified condition

2 – Ground Constant Continuity

3 – Ground Constant Continuity

1 – Ground Ignition switch ON Battery positive voltage

5 – Ground Constant Battery positive voltage

If circuit is not as specified, inspect the circuits connected to oth­er parts.

2000 LEXUS LS400 (RM717U)

2061Author!: Date!:

–BODY ELECTRICAL SEAT HEATER SYSTEM

BE–199

Seat Cushion Side

6. Seat Cushion:
INSPECT SEAT HEATER CONTINUITY

(a) Heat the thermostat with a light.
(b) Inspect the seat heater continuity between terminals.

Connector ”A”

Connector ”B”

Te s te r c o nn e c t i on Condition Specified condition

A2 – B3 Constant Continuity

A1 – B1 Seat heater temperature bellow 25°C (77°F) Continuity

B1 – B2 Seat heater temperature bellow 25°C (77°F) Continuity

A1 – B2 Seat heater temperature bellow 25°C (77°F) Continuity

A1 – B1

B1 – B2

A1 – B2

Z14754

Seat heater temperature above
55°C (131°F)

Seat heater temperature above
45°C (113°F)

Seat heater temperature above
45°C (113°F)

No continuity

No continuity

No continuity

If continuity is not as specified, replace the seat cushion pad.

Seat Back Side

Te s te r c o nn e c t i on Condition Specified condition

1 – 3 Constant Continuity

2 – 3 Constant Continuity

2000 LEXUS LS400 (RM717U)

7. Seat Back:
INSPECT SEAT HEATER CONTINUITY

Inspect the seat heater continuity between terminals, as
shown.

Z14755

If continuity is not as specified, replace the seat back pad.

2062Author!: Date!:

BE–196

SEAT HEATER SYSTEM

LOCATION

–

BE0CT–01

Engine Room Junction Block

! FR S/HTR Fuse
! Engine Main Relay

Seat Heater
(Seat Back)

Seat Heater
(Seat Cushion)

Seat Heater Switch

I03404

2059Author!: Date!:

BE–194

–BODY ELECTRICAL ELECTRO CHROMIC MIRROR SYSTEM

BE0CS–01

INSPECTION

1. INSPECT ELECTRO CHROMIC INNER MIRROR OP­ERATION

(a) Connect the positive (+) lead from the battery to terminal

1 and the negative (–) lead to terminal 4.

(b) Connect the positive (+) leaf from the voltmeter to terminal

2 and the negative (–) lead to terminal 3.

(c) Shine an electric light on the mirror, and check that there

is battery positive voltage and mirror surface becomes
”bright” to ”dark”.

If operation is not as specified, replace the inner mirror.

Wire Harness Side

Te s te r c o nn e c t i on Condition Specified condition

4 – Ground Constant Continuity

1 – Ground Ignition switch LOCK or ACC No voltage

1 – Ground Ignition switch ON Battery positive voltage

N16074

2. INSPECT ELECTRO CHROMIC INNER MIRROR CIR­CUIT

Disconnect the connector from the mirror and inspect the con­nector on the wire harness side, as shown.
If circuit is not as specified, inspect the circuits connected to oth­er parts.

Z14965

2000 LEXUS LS400 (RM717U)

2057Author!: Date!:

–BODY ELECTRICAL ELECTRO CHROMIC MIRROR SYSTEM

BE–195

”Bright”

”Dark”

”Bright”

”Dark”

w/o Memory

w/ Memory

4

3

N17035

I04603

3. INSPECT ELECTRO CHROMIC OUTER MIRROR OP­ERATION
w/o Driving position memory:

(a) Disconnect the outer mirror connector.
(b) Connect the positive (+) lead from the dry through battery

to terminal 2 and the negative (–) lead to terminal 1, then
check that the mirror surface become ”dark”.

(c) Reconnect to the dry through battery by the reverse order,

then check that the mirror surface become ”bright”.

If operation is not as specified, replace the mirror assembly.

4. INSPECT ELECTRO CHROMIC OUTER MIRROR OP­ERATION
w/ Driving position memory:

(a) Disconnect the outer mirror connector.
(b) Connect the positive (+) lead from the dry through battery

to terminal 4 and the negative (–) lead to terminal 3, then
check that the mirror surface become ”dark”.

(c) Reconnect to the dry through battery by the reverse order,

then check that the mirror surface become ”bright”.

If operation is not as specified, replace the mirror assembly.

2000 LEXUS LS400 (RM717U)

2058Author!: Date!:

–

ELECTRO CHROMIC MIRROR SYSTEM

LOCATION

Ignition Switch

BE–193

BE0CR–01

Instrument Panel
Junction Block
! ECU–IG Fuse

Electro Chromic Inner Mirror

I03408

2056Author!: Date!:

Slider

Upward

4

Downward

1

4

BE–187

–BODY ELECTRICAL POWER SHOULDER BELT ANCHORAGE SYSTEM

BE0CQ–01

(b)(a)

1

INSPECTION

1. INSPECT DRIVER’S HEIGHT ADJUSTABLE ANCHOR
MOTOR AND SENSOR OPERATION

(a) Connect the positive (+) lead from the battery to terminal

4 and the negative (–) lead to terminal 1, and check that
the slider moves upward.

(b) Reverse the polarity and check that the slider moves

downward.

N13338

If operation is not as specified, replace the height adjustable an­chor motor.

2. Inspection using an ammeter:

4

1

INSPECT DRIVER’S HEIGHT ADJUSTABLE ANCHOR
MOTOR AND SENSOR PTC THERMISTOR OPERA­TION

(a) Connect the positive (+) lead from the battery to terminal

1, the positive (+) lead from the ammeter to terminal 4,
and the negative (–) lead to battery negative (–) terminal,
then move the slider to end position.

N13339

(b) Continue to apply voltage and check the current changes

to less than 0.1 A within 6 to 46 seconds.

(c) Disconnect the leads from terminals.

4

1

(d) Approximately 60 seconds later, connect the positive (+)

lead from battery to terminal 4 and the negative (–) lead
to terminal 1, and check that the slider moves to the oppo­site side.

If operation is not as specified, replace the height adjustable an­chor motor.

N13340

2000 LEXUS LS400 (RM717U)

2050Author!: Date!:

BE–188

–BODY ELECTRICAL POWER SHOULDER BELT ANCHORAGE SYSTEM

3. Inspection using an ammeter with a current–measur-

4

1

ing probe:
INSPECT DRIVER’S HEIGHT ADJUSTABLE ANCHOR
MOTOR AND SENSOR PTC THERMISTOR OPERA­TION

(a) Connect the positive (+) lead from the battery to terminal

1 and the negative (–) lead to terminal 4.

(b) Attach a current–measuring probe to the negative (–)

N13380

lead, and move the slider to the end position.

(c) Check the current changes to less than 0.1 A with 6 to 46

seconds.

Slider

Upward

2

4

Downward

2

1

1

1

N13340

N13341

(d) Disconnect the leads from terminals.
(e) Approximately 60 seconds later, reverse the polarity, and

check that the slider moves to the opposite side.

If operation is not as specified, replace the height adjustable an­chor motor.

4. INSPECT PASSENGER’S HEIGHT ADJUSTABLE AN­CHOR MOTOR AND SENSOR OPERATION

(a) Connect the positive (+) lead from the battery to terminal

2 and the negative (–) lead to terminal 1, and check that
the slider moves upward.

(b) Reverse the polarity and check that the slider moves

downward.

If operation is not as specified, replace the height adjustable an­chor motor.

2000 LEXUS LS400 (RM717U)

2051Author!: Date!:

BE–189

–BODY ELECTRICAL POWER SHOULDER BELT ANCHORAGE SYSTEM

5. Inspection using an ammeter:

2

1

INSPECT PASSENGER’S HEIGHT ADJUSTABLE AN­CHOR MOTOR AND SENSOR PTC THERMISTOR OP­ERATION

(a) Connect the positive (+) lead from the battery to terminal

1, the positive (+) lead from the ammeter to terminal 2,
and the negative (–) lead to battery negative (–) terminal,
then move the slider to end position.

N13342

(b) Continue to apply voltage and check the current changes

to less than 0.1 A within 6 to 46 seconds.

(c) Disconnect the leads from terminals.

(d) Approximately 60 seconds later, connect the positive (+)

2

1

lead from battery to terminal 2 and the negative (–) lead
to terminal 1, and check that the slider moves to the oppo­site side.

If operation is not as specified, replace the height adjustable an­chor motor.

N13343

6. Inspection using an ammeter with a current–measur-

2

1

ing probe:
INSPECT PASSENGER’S HEIGHT ADJUSTABLE AN­CHOR MOTOR AND SENSOR PTC THERMISTOR OP­ERATION

(a) Connect the positive (+) lead from the battery to terminal

1 and the negative (–) lead to terminal 2.

(b) Attach a current–measuring probe to the negative (–)

N13344

lead, and move the slider to the end position.

(c) Check the current changes to less than 0.1 A within 6 to

46 seconds.

2000 LEXUS LS400 (RM717U)

2052Author!: Date!:

BE–190

Up

Down

–BODY ELECTRICAL POWER SHOULDER BELT ANCHORAGE SYSTEM

(d) Disconnect the leads from terminals.

2

1

(e) Approximately 60 seconds later, reverse the polarity and

check that the slider moves to the opposite side.

If operation is not as specified, replace the height adjustable an­chor motor.

N13343

7. INSPECT DRIVER’S SHOULDER BE LT ADJUST
SWITCH CIRCUIT (See page DI–755)

8. INSPECT DRIVER’S SHOULDER BE LT ADJUST
SWITCH CONTINUITY

Switch position Te s te r c o nn e c t i on Specified condition

UP 2 – 3 Continuity

OFF – No continuity

Z08899

9. INSPECT PASSENGER’S SHOULDER BELT ADJUST

DOWN 1 – 3 Continuity

SWITCH CONTINUITY

Wire Harness Side

h–7–1

Te s te r c o nn e c t i on Condition Specified condition

6 – Ground Constant Continuity

7 – Ground Constant Continuity

Switch position Te s te r c o nn e c t i on Specified condition

UP 1 – 7 Continuity

OFF – No continuity

DOWN 2 – 6 Continuity

If continuity is not as specified, replace the switch.

10. INSPECT PASSENGER’S SHOULDER BELT ADJUST
SWITCH CIRCUIT

Disconnect the connector from the switch and inspect the con­nector on the wire harness side, as shown.

Z08795

If circuit is not as specified, inspect wire harness.

2000 LEXUS LS400 (RM717U)

2053Author!: Date!:

BE–191

–BODY ELECTRICAL POWER SHOULDER BELT ANCHORAGE SYSTEM

11. Upward:

1

4

INSPECT SHOULDER BELT ANCHOR RELAY OPERA­TION

(a) Connect the positive (+) lead from the battery to terminal

7

5

4 and the negative (–) lead to terminal 5 and 7.

(b) Connect the positive (+) lead from the voltmeter to termi-

nal 1 and negative (–) lead to battery negative (–) termi­nal, and check that there is battery positive voltage.

N13346

8

Wire Harness Side

S–8–1

3

12. Downward:
INSPECT SHOULDER BELT ANCHOR RELAY OPERA-

4

TION

(a) Connect the positive (+) lead from the battery to terminal

7

4 and the negative (–) lead to terminal 7 and 8.

(b) Connect the positive (+) lead from the voltmeter to termi-

nal 3 and negative (–) lead to battery negative (–) termi­nal, and check that there is battery positive voltage.

N13347

If operation is not as specified, replace rheostat light control.

13. INSPECT SHOULDER BELT ANCHOR RELAY CIR­CUIT

Disconnect the connector from the rheostat light control and in­spect the connector on the wire harness side, as shown.

Z14752

Te s te r c o nn e c t i on Condition Specified condition

5 – Ground Seat belt adjust switch position UP Continuity

7 – Ground Constant Continuity

8 – Ground Seat belt adjust switch position DOWN Continuity

4 – Ground Constant Battery positive voltage

2000 LEXUS LS400 (RM717U)

If circuit is not as specified, inspect the circuits connected to oth­er parts.

2054Author!: Date!:

BE–192

–BODY ELECTRICAL POWER SHOULDER BELT ANCHORAGE SYSTEM

Wire Harness Side

Connector ”A”

Connector ”B”

e–12–1
h–22–1

Te s te r c o nn e c t i on Condition Specified condition

A7 – Ground

B9 – Ground

A4 – Ground

B22 – Ground

B15 – Ground Ignition switch turned to ON Battery positive voltage

A6 – B8

B8 – B17 Constant Approx. 4 – 6 kΩ

14. INSPECT TILT AND TELESCOPIC ECU CIRCUIT

Disconnect the ECU connector, and inspect the connector on
wire harness side, as shown.

Z14981

Constant Continuity

Constant Battery positive voltage

Move the driver’s height adjustable

anchor sensor

Resistance changes from Approx. 0 to 5 kΩ

If circuit is not as specified, inspect the circuit connected to oth­er parts.

2000 LEXUS LS400 (RM717U)

2055Author!: Date!:

BE–186

–

POWER SHOULDER BELT ANCHORAGE SYSTEM

LOCATION

Tilt and Telescopic ECU

BE0CP–01

Driver Door ECU

Drive Position Memory
and Return Switch
! Shoulder Belt Adjust Switch

Ignition Switch

Power Shoulder
Belt Anchor Relay

Shoulder Belt Adjust Switch

Height Adjustable Anchor Motor

I03235

2049Author!: Date!:

BE–182

Left/Right Adjustment Switch

9

8

7

6

5

Mirror Switch

I04167

–BODY ELECTRICAL POWER MIRROR CONTROL SYSTEM

BE11W–01

INSPECTION

1. INSPECT MIRROR SWITCH CONTINUITY

Switch position Te s te r c o nn e c t i on Resistance (Ω)

LEFT 8 – 9 100

RIGHT 8 – 9 0

Illumination 5 – 6 Continuity

If continuity is not as specified, replace the switch.

2. INSPECT MIRROR SWITCH RESISTANCE

Measure resistance between terminals 7 and 9 at each switch
position, as shown in the chart.

Switch position Resistance (Ω)

UP Approx. 100

RIGHT 250

DOWN 470

LEFT 800

If resistance is not as specified, replace the switch.

3. INSPECT MIRROR SWITCH CIRCUIT
(See page DI–452)

6

5

RETURN RETRACT

3

N13659

2

1

I09236

4

4. INSPECT MIRROR SWITCH INDICATOR LIGHT OP­ERATION

Connect the positive (+) lead from the battery to terminal 5 and
the negative (–) lead to terminal 6, and check that the indicator
light does not light up, replace the switch.

5. CANADA and TAIWAN models only:
INSPECT RETRACT SWITCH CONTINUITY

Switch position Te s te r c o nn e c t i on Specified condition

RETURN – No continuity

RETRACT 1 – 2 Continuity

6. CANADA and TAIWAN models only:
INSPECT RETRACT SWITCH INDICATOR OPERA­TION

Connect the positive (+) lead from the battery to terminal 4 and
negative (–) lead to terminal3 and check that the indicator does
no light up, replace the switch.

2000 LEXUS LS400 (RM717U)

I09237

2045Author!: Date!:

N13476

BE–183

–BODY ELECTRICAL POWER MIRROR CONTROL SYSTEM

7. INSPECT MIRROR MOTOR OPERATION
w/o Driving position memory:

(a) Connect the positive (+) lead from the battery to terminal

6 and negative (–) lead to terminal 5, then check that the
mirror turns to left side.

(b) Reverse the polarity and check that the mirror turns to

right side.

(c) Connect the positive (+) lead from the battery to terminal

4 and negative (–) lead to terminal 5, then check that the
mirror turns upward.

(d) Reverse the polarity and check that the mirror turns down-

ward.

12 11

11 10

12 11

11 10

N13477

8. INSPECT MIRROR MOTOR OPERATION
w/ Driving position memory:

(a) Connect the positive (+) lead from the battery to terminal

11 and negative (–) lead to terminal 12, then check that
the mirror turns to left side.

(b) Reverse the polarity and check that the mirror turns to

right side.

I04601

(c) Connect the positive (+) lead from the battery to terminal

11 and negative (–) lead to terminal 10, then check that
the mirror turns upward.

(d) Reverse the polarity and check that the mirror turns down-

ward.

I04602

7

13

11

10

2000 LEXUS LS400 (RM717U)

9. INSPECT MIRROR POSITION SENSORS

HINT:
Strip off the vinyl tape of the connector and remove terminals
6, 7, 10, 11, 12, 13 and 14 from the connector housing.

6

(a) Connect a series of three 1.5 V dry cell batteries.
(b) Connect the positive (+) lead from the dry cell batteries to

terminal 7 and the negative (–) lead to terminal 6.

(c) Connect the positive (+) lead from the voltmeter to termi-

I04605

nal 13 and the negative (–) lead to terminal 6.

2046Author!: Date!:

BE–184

14

12

14

12

13

11

–BODY ELECTRICAL POWER MIRROR CONTROL SYSTEM

(d) Apply battery positive voltage to terminals 10 and 11, then

check that the voltage gradually changes according to the

7

table below while the mirror moves between the upper­most position and lowermost position.

10

6

I04606

Mirror

position

Voltage 2.8 – 5.0

Lowermost

If voltage value is not as specified, replace the motor assembly.

Mirror

position

Changes

gradually

Uppermost

0 – 0.9

(e) Disconnect the 4 leads of the battery and voltmeter.
(f) Connect the positive (+) lead from the voltmeter to termi-

7

nal 14 and negative (–) lead to terminal 6.

(g) Apply battery positive voltage to terminals 11 and 12, then

6

inspect that the voltage gradually changes according to
the table below while the mirror moves between the left–

11

I04607

7

most position and right–most position.

Mirror

position

Voltage

LEFT

Voltage

RIGHT

Left–most

2.8 – 5.0

0 – 0.9

Mirror

position

Changes

gradually

Changes

gradually

Right–most

0 – 0.9

2.8 –5.0

If voltage value is not as specified, replace the motor assembly.

6

11

SW1

SW2

SET Switch

I04608

N13484

10. INSPECT DRIVING POSITION MEMORY AND RE­TURN SWITCH CONTINUITY

Switch position Te s te r c o nn e c t i on Specified condition

SET switch ON 3 – 4 Continuity

Return SW1 ON 3 – 7 Continuity

Return SW2 ON 3 – 6 Continuity

If continuity is not as specified, replace the switch.
If continuity is as specified, inspect the switch circuit.

11. INSPECT DRIVING POSITION MEMORY AND RE­TURN SWITCH CIRCUIT (See page DI–755)

2000 LEXUS LS400 (RM717U)

2047Author!: Date!:

BE–185

–BODY ELECTRICAL POWER MIRROR CONTROL SYSTEM

12. INSPECT ELECTRICAL RETRACT MOTOR CONTINU-

2

1

ITY

(a) Connect the positive (+) lead from the battery to terminal

2 and negative (–) lead to terminal 1, check that the no
continuity exists in folding position.

(b) Reverse the polarity, check that no continuity exists in

driving position.

If operation is not as specified, replace the mirror assembly.

I09238

13. INSPECT ELECTRICAL RETRACT MOTOR CONTINU-

2

1

ITY
At drive position:

(a) Connect the positive (+) lead from the battery to terminal

2 and negative (–) lead to terminal 1, check that continuity
exists in folding position.

(b) Reverse the polarity, check that no continuity exists in

driving position.

I09239

If operation is not as specified, replace the mirror assembly.

14. INSPECT ELECTRICAL RETRACT MOTOR CONTINU-

2

1

ITY
Between drive position and retract position:

(a) Connect the positive (+) lead from the battery to terminal

2 and negative (–) lead to terminal 1, check that continuity
exists in folding position.

(b) Reverse the polarity, check that no continuity exists in

driving position.

I09240

If operation is not as specified, replace the mirror assembly.

15. INSPECT MIRROR MOTOR OPERATION

1

2

(a) Connect the positive (+) lead from the battery to terminal

2 and negative (–) lead to terminal 1.

(b) Check that the motor turns (moves to folding position).

NOTICE:
These tests must be performed quickly (within 5 – 10 se­conds) to prevent the coil from burning out.

I09241

(c) Connect the positive (+) lead from the battery to terminal

2

1

1 and negative (–) lead to terminal 2.

(d) Check that the motor turns (moves to driving position).

NOTICE:
These tests must be performed quickly (within 5 – 10 se­conds) to prevent the coil from burning out.

If operation is not as specified, replace the mirror assembly.

2000 LEXUS LS400 (RM717U)

I09242

2048Author!: Date!:

–

POWER MIRROR CONTROL SYSTEM

LOCATION

BE–181

BE0CN–01

Engine Room Junction Block
! HORN Fuse

Ignition Switch

Tilt & Telescopic ECU

Body ECU

Driver Door ECU

Instrument Panel Junction Block
! RADIO No.2 Fuse

Front Passenger Door ECU

Driving Position Memory
& Return Switches

I03406

2044Author!: Date!:

Front vertical Rear vertical

UP

DOWN

Slide

UP

DOWN

BACKFRONT

Z16936

–BODY ELECTRICAL POWER SEAT CONTROL SYSTEM (w/o Driving

Position Memory)

BE–171

BE121–01

INSPECTION

1. INSPECT FRONT POWER SEAT SWITCH CONTINU­ITY

Slide switch

Switch position Te s te r c o nn e c t i on Specified condition

FRONT

OFF

BACK

Front vertical switch

Switch position Te s te r c o nn e c t i on Specified condition

UP

OFF

DOWN

Rear vertical switch

11 – 14

12 – 13

11 – 13

12 – 13

11 – 13

12 – 14

9 – 14

10 – 13

9 – 13

10 – 13

9 – 13

10 – 14

Continuity

Continuity

Continuity

Continuity

Continuity

Continuity

Reclining

FORWARD

DOWN

UP

REAR

Head Rest

Switch position Te s te r c o nn e c t i on Specified condition

UP

OFF

DOWN

5 – 14

6 – 13

5 – 13

6 – 13

5 – 13

6 – 14

Continuity

Continuity

Continuity

Reclining switch

Switch position Te s te r c o nn e c t i on Specified condition

FORWARD

OFF

REAR

4 – 14

3 – 13

4 – 13

3 – 13

4 – 13

3 – 14

Continuity

Continuity

Continuity

Headrest switch

Switch position Te s te r c o nn e c t i on Specified condition

UP

OFF

DOWN

14 – 15

13 – 16

13 – 15

13 – 16

13 – 15

14 – 16

Continuity

Continuity

Continuity

If continuity is not as specified, replace the switch.

2000 LEXUS LS400 (RM717U)

Z16937

2034Author!: Date!:

BE–172

–BODY ELECTRICAL POWER SEAT CONTROL SYSTEM (w/o Driving

Position Memory)

Wire Harness Side

1

2

7

5

6

13

11

12

Te s te r c o nn e c t i on Condition Specified condition

13 – Ground Constant Continuity

14 – Ground Constant Battery positive voltage

14

2. INSPECT POWER SEAT SWITCH CIRCUIT

(a) Disconnect the switch connector and connect the seat

wire harness to the floor wire harness.

(b) Inspect the connector on the wire harness side, as

4

3

8

10

9

16

15

Z09315

shown.

If circuit is not as specified, inspect the circuits connected to oth­er parts.

3. INSPECT LUMBAR SUPPORT SWITCH CONTINUITY
( ): Passenger’s Seat

FORWARD RELEASE

Z07464

Switch position Te s te r c o nn e c t i on Specified condition

FORWARD

OFF

RELEASE

1(1) – 4(4)

2(2) – 3(3)

1(2) – 3(3)

2(2) – 3(4)

1(1) – 3(3)

2(2) – 4(4)

Continuity

Continuity

Continuity

If continuity is not as specified, replace the switch.

2000 LEXUS LS400 (RM717U)

2035Author!: Date!:

–BODY ELECTRICAL POWER SEAT CONTROL SYSTEM (w/o Driving

Position Memory)

BE–173

Wire Harness Side

4. INSPECT LUMBAR SUPPORT SWITCH CIRCUIT

(a) Disconnect the switch connector and connect the seat

wire harness to the floor wire harness.

(b) Inspect the connector on the wire harness side, as

shown.

Z06678

( ): Passenger’s Seat

Te s te r c o nn e c t i on Condition Specified condition

3 – Ground (2 – Ground) Constant Continuity

4 – Ground (1 – Ground) Constant Battery positive voltage

If circuit is not as specified, inspect the circuits connected to oth­er parts.

5. INSPECT SLIDE MOTOR OPERATION

(a) Connect the positive (+) lead from the battery to terminal

2 and the negative (–) lead to terminal 1 and check that
the motor turns counterclockwise.

(b) Reverse the polarity and check that the motor turns clock-

wise.

21

–+

N07798

If operation is not as specified, replace the motor.

2000 LEXUS LS400 (RM717U)

2

–

+

2

–+

1

–+

1

Z14972

Z07885

6. Driver’s seat:
INSPECT SLIDE MOTOR PTC THERMISTOR OPERA­TION

(a) Connect the positive (+) lead from the battery to terminal

2, the positive (+) lead from the ammeter to terminal 1,
and the negative (–) lead to battery negative (–) terminal,
then move the seat to front position.

(b) Continue to apply voltage and check that the current

changes to less than 1 ampere with 4 to 90 seconds.

(c) Disconnect the lead from terminals.
(d) Approximately 60 seconds later , connect the positive (+)

lead from battery to terminal 1 and the negative (–) lead
to terminal 2 and check that the seat begins to move back­wards.

If operation is not as specified, replace the motor.

2036Author!: Date!:

BE–174

(a) (b)

–BODY ELECTRICAL POWER SEAT CONTROL SYSTEM (w/o Driving

Position Memory)

7. INSPECT FRONT VERTICAL MOTOR OPERATION

(a) Connect the positive (+) lead from the battery to terminal

2 and the negative (–) lead to terminal 1 and check that
the motor turns clockwise.

(b) Reverse the polarity and check that the motor turns coun-

terclockwise.

If operation is not as specified, replace the motor.

21

–+

21

2

–+

Z14969

1

Z14970

8. Driver’s Seat:
INSPECT FRONT VERTICAL MOTOR PTC THERM­ISTOR OPERATION

(a) Connect the positive (+) lead from the battery to terminal

1, the positive (+) lead from the ammeter to terminal 2 and
the negative (–) lead to battery negative (–) terminal, then
move the front edge of seat cushion to the highest posi­tion.

(b) Continue to apply voltage, and check the current changes

to less than 1 ampere with 4 to 90 seconds.

(c) Disconnect the leads from terminals.
(d) Approximately 60 seconds later, connect the positive (+)

lead from battery to terminal 2 and the negative (–) lead
to terminal 1, and check that the seat cushion begins to
descend.

If operation is not as specified, replace the motor.

21

2000 LEXUS LS400 (RM717U)

Z07887

9. INSPECT REAR VERTICAL MOTOR OPERATION

(a) Connect the positive (+) lead from the battery to terminal

2 and the negative (–) lead to terminal 1, and check that
the motor turns clockwise.

(b) Reverse the polarity, and check that the motor turns coun-

terclockwise.

If operation is not as specified, replace the motor.

–+

N07798

2037Author!: Date!:

2

2

–+

1

–+

1

Z14971

–BODY ELECTRICAL POWER SEAT CONTROL SYSTEM (w/o Driving

Position Memory)

BE–175

10. Driver’s seat:
INSPECT REAR VERTICAL MOTOR PTC THERM­ISTOR OPERATION

(a) Connect the positive (+) lead from the battery to terminal

2, the positive (+) lead from the ammeter to terminal 1 and
the negative (–) lead to battery negative (–) terminal, then
move the rear edge of seat cushion to the highest posi­tion.

(b) Continue to apply voltage, and check that the current

changes to less than 1 ampere with 4 to 90 seconds.

(c) Disconnect the leads from terminals.
(d) Approximately 60 seconds later, connect the positive (+)

lead from battery to terminal 1 and the negative (–) lead
to terminal 2, and check that the seat cushion begins to
descend.

If operation is not as specified, replace the motor.

(a) (b)

21

–+

21

Z07469

11. Driver’s Seat:
INSPECT RECLINING MOTOR OPERATION

(a) Connect the positive (+) lead from the battery to terminal

2 and the negative (–) lead to terminal 1, and check that
the motor turns counterclockwise.

(b) Reverse the polarity, and check that the motor turns

clockwise.

If operation is not as specified, replace the motor.

–+

Z14969

2000 LEXUS LS400 (RM717U)

12. Driver’s Seat:

2

1

INSPECT RECLINING MOTOR PTC THERMISTOR OP­ERATION

(a) Connect the positive (+) lead from the battery to terminal

1, the positive (+) lead from the ammeter to terminal 2 and
the negative (–) lead to battery negative (–) terminal, then

–
+

–+

Z14973

recline the seat back to the most forward position.

(b) Continue to apply voltage, and check that the current

change to less than 1 ampere with 4 to 90 seconds.

2038Author!: Date!:

BE–176

(c) Disconnect the lead from terminals.

21

(d) Approximately 60 seconds later, connect the positive (+)

If operation is not as specified, replace the motor.

–+

Z07474

13. INSPECT LUMBAR SUPPORT MOTOR OPERATION

21

(a) Connect the positive (+) lead from the battery to terminal

–BODY ELECTRICAL POWER SEAT CONTROL SYSTEM (w/o Driving

Position Memory)

lead from battery to terminal 2 and the negative (–) lead
to terminal 1, check that the seat back starts to fall back­wards.

1 and the negative (–) lead to terminal 2, and check that
the lumbar support moves release side.

N21675

(b) Reverse the polarity, and check that the lumbar support

21

If operation is not as specified, replace the motor.

N21676

14. Driver’s Seat:

21

(a) Connect the positive (+) lead from the battery to terminal

N13487

2

1

(b) Continue to apply voltage, and check that the current

(c) Disconnect the leads from terminals.
(d) Approximately 60 seconds later, connect the positive (+)

If operation is not as specified, replace the motor.

moves forward.

INSPECT LUMBAR SUPPORT MOTOR PTC THERM­ISTOR OPERATION

1, the positive (+) lead from the ammeter to terminal 2 and
the negative (–) lead to battery negative (–) terminal, then
move the front edge of seat cushion to the highest posi­tion.

changes to less than 1 ampere with 4 to 90 seconds.

lead from battery to terminal 2 and the negative (–) lead
to terminal 1, and check that the seat cushion begins to
descend.

2000 LEXUS LS400 (RM717U)

N13488

2039Author!: Date!:

FRONT

UP

DOWN

REAR

Connector ”A”

FRONT

REAR

Connector ”B”

I09308

–BODY ELECTRICAL POWER SEAT CONTROL SYSTEM (w/o Driving

Position Memory)

15. Taiwan Models Only:
INSPECT REAR POWER SEAT SWITCH CONTINUITY

Slide switch LH:

Switch position Te s te r c o nn e c t i on Specified condition

FRONT

OFF

REAR

B1 – B5

B5 – B7

B1 – B7

B5 – B7

B1 – B7

B5 – B6

Continuity

Continuity

Continuity

Slide switch RH:

Switch position Te s te r c o nn e c t i on Specified condition

FRONT

OFF

REAR

B4 – B6

B9 – B7

B4 – B7

B7 – B10

B4 – B7

B7 – B10

Continuity

Continuity

Continuity

Headrest switch LH (for vertical):

BE–177

Switch position Te s te r c o nn e c t i on Specified condition

UP

OFF

DOWN

B2 – B6

B7 – B8

B2 – B7

B7 – B8

B2 – B7

B6 – B8

Continuity

Continuity

Continuity

Headrest switch RH (for vertical):

Switch position Te s te r c o nn e c t i on Specified condition

UP

OFF

DOWN

B3 – B6

B7 – B9

B3 – B7

B7 – B9

B3 – B7

B6 – B9

Continuity

Continuity

Continuity

Headrest switch LH (for turning)

Switch position Te s te r c o nn e c t i on Specified condition

FRONT A4 –B7 Continuity

OFF – No continuity

REAR A5 –B7 Continuity

Headrest switch RH (for turning)

2000 LEXUS LS400 (RM717U)

Switch position Te s te r c o nn e c t i on Specified condition

FRONT A4 –B7 Continuity

OFF – No continuity

REAR A5 –B7 Continuity

If continuity is not as specified, replace the switch.

2040Author!: Date!:

BE–178

–BODY ELECTRICAL POWER SEAT CONTROL SYSTEM (w/o Driving

Position Memory)

Wire Harness Side

Connector ”A”

Te s te r c o nn e c t i on Condition Specified condition

B7 – Ground Constant Continuity

B8 – Ground Constant Battery positive voltage

21

Connector ”B”

–+

16. INSPECT REAR POWER SEAT SWITCH CIRCUIT

(a) Disconnect the switch connector and connect the seat

wire harness to the floor wire harness.

(b) Inspect the connector on the wire harness side, as

shown.

I10509

If circuit is not as specified, inspect the circuits connected to oth­er parts.

17. INSPECT SLIDE MOTOR OPERATION

(a) Connect the positive (+) lead from the battery to terminal

2 and the negative (–) lead to terminal 1 and check that
the motor turns counterclockwise.

(b) Reverse the polarity and check that the motor turns clock-

wise.

If operation is not as specified, replace the motor.

N07798

2000 LEXUS LS400 (RM717U)

18. INSPECT SLIDE MOTOR PTC THERMISTOR OPERA-

2

1

TION

(a) Connect the positive (+) lead from the battery to terminal

2, the positive (+) lead from the ammeter to terminal 1,
and the negative (–) lead to battery negative (–) terminal,
then move the seat to front position.

(b) Continue to apply voltage and check that the current

changes to less than 1 ampere with 4 to 90 seconds.

I09301

(c) Disconnect the lead from terminals.

2

1

(d) Approximately 60 seconds later , connect the positive (+)

lead from battery to terminal 1 and the negative (–) lead
to terminal 2 and check that the seat begins to move back­wards.

If operation is not as specified, replace the motor.

I09300

2041Author!: Date!:

(a) (b)

21

21

–BODY ELECTRICAL POWER SEAT CONTROL SYSTEM (w/o Driving

Position Memory)

BE–179

19. INSPECT HEADREST MOTOR OPERATION
(For vertical)

(a) Connect the positive (+) lead from the battery to terminal

2 and the negative (–) lead to terminal 1, and check that
the motor turns counterclockwise.

(b) Reverse the polarity, and check that the motor turns

clockwise.

If operation is not as specified, replace the motor.

To ”DOWN”

I09261

20. INSPECT HEADREST MOTOR CIRCUIT BREAKER

1

OPERATION (For vertical)

(a) Connect the positive (+) lead from the battery to terminal

1 and negative (–) lead to terminal 2 on the motor connec-

2

I09282

tor and move the headrest to DOWN position.

(b) Continue to apply voltage, check that there is a circuit

1

breaker operation noise within 4 to 60 seconds.

(c) Reverse the polarity check that the headrest begins to

move UP side within approx. 60 seconds.

2

I09281

If operation is not as specified, replace the headrest.

2000 LEXUS LS400 (RM717U)

2042Author!: Date!:

BE–180

–BODY ELECTRICAL POWER SEAT CONTROL SYSTEM (w/o Driving

Position Memory)

FRONT

REAR

2

1

21. INSPECT HEADREST MOTOR OPERATION
(For turning)

(a) Connect the positive (+) lead from the battery to terminal

2 and negative (–) lead to terminal 4.

4

3

(b) Connect the negative (–) lead to each terminal and check

that the headrest turns at each position, as shown in the
chart.

Te s te r c o nn e c t i on Position

I09283

1 FRONT

3 REAR

If operation is not as specified, replace the headrest.

2000 LEXUS LS400 (RM717U)

2043Author!: Date!:

–BODY ELECTRICAL POWER SEAT CONTROL SYSTEM (w/o Driving

Position Memory)

POWER SEAT CONTROL SYSTEM (w/o Driving Position
Memory)

LOCATION

Engine Room
Junction Block
! FR S/HTR Fuse

BE–169

BE120–01

Lumbar Support Motor

Lumbar Support Switch

Poser Seat Switch

Front Vertical Motor

Slide Motor

Reclining Motor

Lumbar Support
Motor

Lumbar Support Motor

Lumbar Support Switch

Rear Vertical Motor

Poser Seat Switch

Slide Motor

Front Vertical Motor

I03262

2000 LEXUS LS400 (RM717U)

2032Author!: Date!:

BE–170

TAIWAN models:

–BODY ELECTRICAL POWER SEAT CONTROL SYSTEM (w/o Driving

Position Memory)

Headrest Motor RH
(for turning)

Headrest Motor RH
(for vertical)

Rear Power Seat Switch

Headrest Motor LH
(for turning)

Headrest Motor LH
(for vertical)

Slide Motor RH

Slide Motor LH

I09274

2000 LEXUS LS400 (RM717U)

2033Author!: Date!:

BE–164

I04154

–BODY ELECTRICAL WIRELESS DOOR LOCK CONTROL SYSTEM

BE0CK–01

REPLACEMENT

1. REPLACE TRANSMITTER (LITHIUM) BATTERY

NOTICE:
Special caution should be taken for handling each compo­nent as they are precision electronic components.

(a) Using a screwdriver, remove the screw and cover.

NOTICE:
Do not pry out the cover forcibly.

HINT:
Push the cover with a finger as shown in the illustration, so that
there becomes clearance, then pry out the cover from that
clearance.
(b) Remove the transmitter.

O–Ring

Terminal

I04155

I04156

(c) Using a screwdriver, remove the 2 screws and cover.
(d) Remove the battery (lithium battery).

NOTICE:

! Do not push the terminals with a finger.
! If prying up the battery (lithium battery) forcibly to re-

move, the terminals are deformed.

(e) Install a battery (lithium battery) as shown in the illustra-

tion.

NOTICE:
Face the battery upward. Take care not to deform the termi­nals.

(f) Check that O–ring is not distorted or slipped off, and

install the cover.

(g) Using a screwdriver, tighten the 2 screws.

NOTICE:
When the shrews are tightened loosely, it might cause
faulty contact of battery (lithium battery) and terminals.

(h) Assemble the transmitter to the key plate and the cover.
(i) Using a screwdriver, tighten the screw.

2000 LEXUS LS400 (RM717U)

2027Author!: Date!:

BE–165

–BODY ELECTRICAL WIRELESS DOOR LOCK CONTROL SYSTEM

2. REPLACE DOOR CONTROL RECEIVER AND TRANS­MITTER

NOTICE:
When replacing the door control receiver and transmitter,
registration of recognition code is necessary because they
are provided as a single components.

(a) Select the operation mode to perform from the following

operation modes.

! Add mode
! Rewrite mode
! Prohibition mode
! Confirmation mode

HINT:

! The add mode is used to retain codes already registered

while you register new recognition codes. This mode is
used when adding a transmitter. However, if the number
of registered codes exceeds 4 codes, previously regis­tered codes are correspondingly erased in order, starting
from the first registered code.

! The rewrite mode is used to erase all previously regis-

tered codes and register only new recognition codes.

! The prohibition mode is used to erase all registered codes

and cancels the wireless door lock function. Use this
mode when the transmitter is lost.

! The confirmation mode is for confirming few many recog-

nition codes ar already registered before you register
additional recognition codes.

(b) Follow the chart on the following page to register the

transmitter recognition code at the wireless door lock con­trol receiver.

HINT:

! When procedure is out of the specified, the operation re-

turns to normal operation.

! Maximum 4 recognition codes can be registered.

2000 LEXUS LS400 (RM717U)

2028Author!: Date!:

BE–166

–BODY ELECTRICAL WIRELESS DOOR LOCK CONTROL SYSTEM

Start registration of recognition code

The vehicle should be in the following conditions.

" The key is not inserted in the ignition key cylinder.
" Driver’s door is OPEN. (Other doors are CLOSED)
" Driver’s door is UNLOCKED. (Other doors are CLOSED)

Insert the key into the ignition key cylinder, then pull it out.

Press the door lock control switch (for manual operation) 5 times to
LOCK/UNLOCK at approx. 1 sec. interval.

1st time 2nd time 3rd time 4th time 5th time

Within
40 secs.

Within
40 secs.

LOCK

OFF

UNLOCK

LOCK

OFF

UNLOCK

Approx.
1 sec.

Approx.
1 sec.

Close the driver’s door, then open it.

Again press the door lock control switch (for manual operation) 5 times to
LOCK/UNLOCK at approx. 1 sec. interval.

1st time 2nd time 3rd time 4th time 5th time

Approx.
1 sec.

Approx.
1 sec.

2000 LEXUS LS400 (RM717U)

Insert the key into the ignition key cylinder.

2029Author!: Date!:

BE–167

–BODY ELECTRICAL WIRELESS DOOR LOCK CONTROL SYSTEM

Turn the ignition switch from ON to LOCK at approx. 1 sec. interval 1 to 5 times to select the mode.

Add mode

ON – LOCK change occurs 1 time

Approx. 1 sec.

ON

LOCK

Rewrite mode

ON – LOCK change occurs 2 times

Approx.
1 sec.

Approx.
1 sec.

ON

LOCK

Pull out the key plate from the ignition key cylinder.

When add mode or rewrite mode
is selected.

ON

LOCK

ON

LOCK

Confirmation mode

ON – LOCK change occurs 3 times

Approx.
1 sec.

Approx.
1 sec.

Prohibition mode

ON – LOCK change occurs 5 times

Approx.
1 sec.

Approx.
1 sec.

When prohibition
mode is selected.

When confirmation
mode is selected.

Within
3 secs.

MPX body ECU automatically performs
the LOCK–UNLOCK operation once
or twice at 1 sec, interval to inform the
operator that either the add mode or
rewrite mode has been selected.

LOCK–UNLOCK occurs once

Indicates that add mode has been selected.

1 sec.

LOCK

UNLOCK

LOCK–UNLOCK occurs twice

Indicates that rewrite mode has been
selected.

1 sec.

1 sec.

LOCK

UNLOCK

MPX body ECU automatically performs the
LOCK–UNLOCK operation 1 to 4 times at
2 sec. interval to inform the operator of
the number of the registered codes.
HINT:
When the number of the registered code
is 0, the operation is automatically
performed 5 times.

Example:
When the operation is performed twice, it
directs that 2 type of recognition code
have been registered.

1st time 2nd time

2 secs. 2 secs.

LOCK

UNLOCK

Registration of recognition code (Confirmation
mode and probation mode) is completed.

2000 LEXUS LS400 (RM717U)

2030Author!: Date!:

BE–168

–BODY ELECTRICAL WIRELESS DOOR LOCK CONTROL SYSTEM

When prohibition
mode is selected.

Within
40 secs.

Within 3 secs.

Within
3 secs.

MPX body performs operates LOCK–UNLOCK operation 5 times at a 1 sec.
interval to inform the operator that prohibition mode has been selected.

Approx.

Approx.

1 sec.

1 sec.

ON

LOCK

Press the lock and unlock switches on the transmitter simultaneously within 1.5 sec.

Press again either of switches on the transmitter for more than 1 sec.

MPX body ECU automatically performs LOCK–UNLOCK operation once or
twice at a 1 sec. interval to inform the operator that it has received the signal
from the transmitter.

LOCK–UNLOCK occurs once

Registration of recognition code is completed

LOCK–UNLOCK occurs twice

Registration of recognition code has not been completed.
" Recognition code received first time and second time did not match.

If they are not performed, the mode returns to the normal mode, then start with
”Start registration of recognition code”.

Proceed to finish registration

Proceed to continue registration

Within 40 secs.

If even one of the following conditions is satisfied, registration of recognition
codes in completed.

" 40 secs. elapses since the MPX body ECU response.
" The driver’s door is closed.
" The key plate is inserted in the ignition key cylinder.
" 4 types recognition codes are registration at one time.

Registration of recognition codes (add mode or rewrite mode) is completed.

2000 LEXUS LS400 (RM717U)

2031Author!: Date!:

BE–160

I04149

–BODY ELECTRICAL WIRELESS DOOR LOCK CONTROL SYSTEM

BE0CJ–01

INSPECTION

1. INSPECT WIRELESS DOOR LOCK TRANSMITTER
OPERATION

HINT:
Refer to ”Wireless door lock control receiver and transmitter re­placement”.
(a) Using a screwdriver, remove the screw and cover.
(b) Remove the battery (lithium battery).

(c) Install a new or normal battery (lithium battery).
HINT:
When a new or normal battery can not be obtained, connect 2
new 1.5 V batteries in series, connect the battery (+) to the bat­tery receptacle side terminal and battery (–) to the bottom termi­nal, then apply 3 V voltage to the transmitter.
(d) In the location where is approx. 1 M away from driver’s

outside handle in the right direction, face the key plate of
the transmitter to the vehicle, and check the transmitter
operation when pressing transmission switch on the side
of the transmitter body.

Standard:

! Remote control of vehicle door lock can be operated.
! LED lights up more than once.

HINT:

! The minimum operation distance differs according to op-

erator, the way of holding, and location.

! As weak wave is used, operation distance might be short-

ened when noise is detected in strong wave or used fre­quency.

(e) Install the battery (lithium battery).
(f) Install a cover so that O–ring is not distorted or slipped off.
(g) Using a screwdriver, tighten the screw.

2000 LEXUS LS400 (RM717U)

2023Author!: Date!:

BE–161

–BODY ELECTRICAL WIRELESS DOOR LOCK CONTROL SYSTEM

2. CHECK BATTERY CAPACITY

HINT:

! Make sure to use the TOYOTA electrical tester.
! With the battery unloaded, judge can not be made wheth-

er the battery is available or not on the test.

! When the transmitter is faulty, the energy amount left in

the battery might not be checked correctly.

! On the lithium battery used for the transmitter, the voltage

more than 2.5 V with the battery unloaded is shown on the
tester until the energy is completely consumed.
Accordingly when inspecting the energy amount left in the
battery, it is necessary to measure the voltage when the
battery is loaded. (1.2 kΩ).

I04150

I04151

(a) Remove the screws and cover using a (–) driver.
(b) Remove the battery (lithium battery) from the transmitter.
(c) Connect the lead to the (–) terminal of the transmitter and

install the battery.

(d) Connect the (+) tester to the (+) battery (lithium battery),

and (–) tester to the lead respectively.

(e) Press one of the transmitting switches on the transmitter

for approx. 1 second.

(f) Press the transmitting switch on the transmitter again to

check the voltage.

Standard: 2.1 V or more

2000 LEXUS LS400 (RM717U)

2024Author!: Date!:

BE–162

–BODY ELECTRICAL WIRELESS DOOR LOCK CONTROL SYSTEM

HINT:

! When the temperature of the battery is low, the judge can

not be made correctly.
When the outcome of the test is less than 2.1 V, conduct
the test again after leaving the battery in the place at 18
°C for more than 30 minutes.

! By auto power off function, the voltage becomes no load

voltage (more than 2.5 V) condition after 0.8 seconds
from the switch was pressed.
Make sure to read the voltage before of it.

! High voltage might be shown 1 to 2 times after leaving the

battery, judge should be made with the voltage shown at
the 3rd time or later.

(g) Disconnect the lead.
(h) Set the battery (lithium battery) in the transmitter.
(i) Install the cover, so that the O–ring is not distorted or

slipped off.

(j) Using a screwdriver, tighten the screws.

N13470

21

I04935

3. INSPECT WIRELESS DOOR LOCK CONTROL CAN­CEL SWITCH

Switch position Te s te r c o nn e c t i on Specified condition

OFF – No continuity

ON 1 – 2 Continuity

If continuity is not as specified, replace the switch.
If continuity is as specified, inspect the switch circuit.

4. INSPECT WIRELESS DOOR LOCK CONTROL CAN­CEL SWITCH CIRCUIT (See page DI–689)

5. INSPECT WIRELESS DOOR LOCK BUZZER OPERA­TION

Connect the positive (+) lead from the ohmmeter to terminal 1
and the negative (–) lead to terminal 2, and measure resistance
approx. 1 kΩ.
If resistance is not as specified, replace the buzzer.

6. INSPECT WIRELESS DOOR LOCK BUZZER CIRCUIT
(See page DI–689)

2000 LEXUS LS400 (RM717U)

2025Author!: Date!:

–BODY ELECTRICAL WIRELESS DOOR LOCK CONTROL SYSTEM

BE–163

Wire Harness Side

Te s te r c o nn e c t i on Condition Specified condition

7 – Ground Constant Continuity

1 – Ground Constant Battery positive voltage

From Back Side

7. Connector disconnected:
INSPECT WIRELESS DOOR LOCK CONTROL RE­CEIVER CIRCUIT

Disconnect the connector from the receiver and inspect the
connector on the wire harness side, as shown.

I04152

If the circuit is not as specified, inspect the circuit connected to
other parts.

8. Connector connected:
INSPECT WIRELESS DOOR LOCK CONTROL RE­CEIVER CIRCUIT

Connect the wire harness side connector to the receiver and in­spect the wire harness side connector from the back side, as
shown.

I04153

Te s te r c o nn e c t i on Condition Specified condition

Ignition switch position OFF

3 – Ground

3 – Ground

4 – Ground

Key removed

Transmitter OFF → ON

Ignition switch position OFF

Key removed

Transmitter OFF → ON

Ignition switch position OFF

Key removed

Transmitter OFF

4.5 – 5.5 V → below 1 V

4.5 – 5.5 V → below 1 V

10 – 14 V

If circuit is as specified, replace the receiver.
If the circuit is not as specified, inspect the circuit connected to
other parts.

2000 LEXUS LS400 (RM717U)

2026Author!: Date!:

–BODY ELECTRICAL WIRELESS DOOR LOCK CONTROL SYSTEM

PRE–CHECK

Only wireless function (Remote control) will not operate.

1

(If a new transmitter or a transmitter of the same type that works properly with the vehicle is not available.)

Make the vehicle in the initialized condition:
The initialized condition is the condition when the following conditions are satisfied.
(1) Key plate has not been inserted in the ignition key cylinder.
(2) All the doors are closed. (Door warning light is off.)
(3) All the doors are locked.
(4) Wireless door lock control switch (Buzzer switch) is ON.

Basic function check:

Under the standard operation, when repeating the operation of UNLOCK and LOCK switch 3 times or more alter­nately, check the UNLOCK–LOCK operation from 3rd time onward.
! Following procedures are standard operation.
(1) Keep about 1 M away to the right direction from the outside handle of a driver’s seat.
(2) Face the transmitter toward the vehicle and press one of transmitter switches for about 1 sec.
<Reference>
! As of the security function, even the wireless function is normal, there may be the case that only UNLOCK opera­tion will not work.
! As of the UNLOCK operation times adjustment function of body customize function, when using LEXUS hand–
held tester to set ”operation twice”, only driver’s seat is unlocked by unlock operation performed once.

BE–153

BE0CI–01

No Yes

Transmitter LED inspection:

Check when pressing UNLOCK switch
and LOCK switch under standard
operation, that the transmitter LED
lights up one more once.

No

Yes

Normal
<Reference>
! Operative distance may differ according to
an operator, the way of holding the transmitter
or position.
! Because weak electric wave is used, when
there is strong wave or noise in the used
frequency ,operation distance might be
shortened.

2000 LEXUS LS400 (RM717U)

2016Author!: Date!: