Honda Prelude 1998 2.2L DOHC Workshop Manual

honda :: Honda Prelude Type-SH L4-2157cc 2.2L
DOHC H22A4 (VTEC) 16V (1998)

> Relays and Modules > Relays and Modules - Accessories and Optional Equipment > Security Control Unit <--> [Alarm Module, (Vehicle Antitheft)] > Component Information > Locations

Security Control Unit: Locations

Above Accelerator Pedal (Dealer Installed Option)

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Security Control Unit: DiagramsSecurity Control Unit

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> Relays and Modules > Relays and Modules - Accessories and Optional Equipment > Antitheft Relay > Component Information > Locations

Antitheft Relay: Locations

Left Side Of Dash (Dealer Installed Option)

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> Relays and Modules > Relays and Modules - Accessories and Optional Equipment > General Module > Component Information > Diagrams > Diagram Information and Instructions

General Module: Diagram Information and Instructions

Circuit Schematics

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Instructions > Page 18

Prelude Type-SH L4-2157cc 2.2L DOHC H22A4 (VTEC) 16V (1998)

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Prelude Type-SH L4-2157cc 2.2L DOHC H22A4 (VTEC) 16V (1998)

Each schematic represents one circuit. A circuit's wires and components are arranged to show current flow, from power at the top of the image, toground, at the bottom.

Shared Circuits

Other circuits may share power or ground terminals or wiring with the circuit shown. A wire that connects one circuit to another, for example, iscut short and has an arrowhead at the end of it pointing in the direction of current flow. Next to the arrowhead is the name of the circuit orcomponent which shares that wiring. To quickly check shared wiring, check the operation of a component it serves. If that component works, youknow the shared wiring is OK.

Connectors

All in-line and fuse box connectors are numbered (C725, C416, etc.). Component connectors are not numbered but are identified by the name ofthe component if the component only has one connector, or by a capital letter (A, B, C, etc.) if the component has more than one connector. Belowmost connector numbers and component names are PHOTO and VIEW numbers. The PHOTO number refers to a photo in the image that showsthe connector's location on the car. The VIEW number refers to an illustration in the image that shows the connector face, wire colors, connector

cavity numbers and other details. The connector cavity numbering sequence begins at the top left corner of the connector as seen from either of theviewpoints. Disregard any numbers molded into the connector housing.

Wires

Wires are identified by the abbreviated names of their colors; the second color is the color of the stripe. Wires are also identified by their locationin a connector. The number "2" next to the male and female wire terminals at C416, for example, means those terminals join in cavity 2 ofconnector C416.

A complete description of schematic symbols is given under wire color abbreviation.Symbols

Component Locations

To see where a component or connector is located on the car, look up its photo number in the component location section. The photo will also tell youthe color of the connector, and how many cavities it has.

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Prelude Type-SH L4-2157cc 2.2L DOHC H22A4 (VTEC) 16V (1998)

If there is no photo number below or beside a component name or a connector, ground or terminal number, look up that name or number in appropriateconnector identification chart. The chart lists how many cavities a connector has, where it's located, and what it connects to. The related illustrationshows the connector's location on the harness & the harness routing.

Ground Distribution Schematics

This sample Ground Distribution schematic shows all of the components that share two ground points.

Inline Connector Circuit Identification

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Instructions > Page 21

Prelude Type-SH L4-2157cc 2.2L DOHC H22A4 (VTEC) 16V (1998)

To see the configuration of a connector's cavities, look up its view number in the connector view section. Each view includes the color of the connector,where it is located and what it connects to.

Use the connector views to help to locate the proper cavity when you need to probe a connector. It can be especially helpful if the connector has morethan one wire of the same color.

Connector views can also be used to help diagnose multiple symptoms in separate circuits which could be caused by a single problem in a connectorshared by those circuits. Here's how:

1. Pick one of the multiple symptoms and look up the schematic for that circuit.2. Make a list of all in-line and fuse box connectors in that schematic.3. Then, in this connector view section, look up each connector on your list to see if circuits related to the other symptoms run through one of them.
If they do, inspect that connector for the problem.

Example:

The blower, rear window defogger, and the windshield wiper, don't work. List all in-line and fuse box connectors in the blower control circuitand then check the connector view section. You find that C324 is common to the rear window defogger circuit and wiper/washer circuit, so you inspectC324 and find the problem, bent terminals.

Power Distribution Schematics

Power Distribution schematics show how power is supplied from the positive battery terminal to various circuits in the car. Refer to the PowerDistribution section to get a more detailed picture of how power is supplied to the circuit you're working on.

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Instructions > Page 22

Prelude Type-SH L4-2157cc 2.2L DOHC H22A4 (VTEC) 16V (1998)

From Battery to Ignition Switch, Fuses and Relays

Individual circuit schematics begin with a fuse. The first half of Power Distribution, however, shows the wiring "upstream" between the batteryand the fuses.

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Prelude Type-SH L4-2157cc 2.2L DOHC H22A4 (VTEC) 16V (1998)

From Fuses to Relays and Components

The second half of Power Distribution shows the wiring "From Fuses to Relays and Components." This can speed your troubleshooting byshowing which circuits share fuses. If Power Distribution shows that an inoperative circuit and another circuit share a fuse, check a component inthe other circuit. If it works, you know the fuse is good and power is available to the inoperative circuit.

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Instructions > Page 24

Prelude Type-SH L4-2157cc 2.2L DOHC H22A4 (VTEC) 16V (1998)

> Relays and Modules > Relays and Modules - Accessories and Optional Equipment > General Module > Component Information > Diagrams > Diagram Information and

Instructions > Page 25

Prelude Type-SH L4-2157cc 2.2L DOHC H22A4 (VTEC) 16V (1998)

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Prelude Type-SH L4-2157cc 2.2L DOHC H22A4 (VTEC) 16V (1998)

Wire Color Abbreviations

The following abbreviations are used to identify wire colors in the circuit schematics:BLK ............................................................................................................................................................................................................................ blackBLU .............................................................................................................................................................................................................................. blueBRN .......................................................................................................................................................................................................................... brownGRN ........................................................................................................................................................................................................................... greenGRY ............................................................................................................................................................................................................................. grayLT BLU ................................................................................................................................................................................................................ light blueLT GRN ............................................................................................................................................................................................................. light greenORN ......................................................................................................................................................................................................................... orangePNK ............................................................................................................................................................................................................................. pinkPUR ........................................................................................................................................................................................................................... purpleRED ............................................................................................................................................................................................................................... redWHT ........................................................................................................................................................................................................................... whiteYEL .......................................................................................................................................................................................................................... yellow

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Prelude Type-SH L4-2157cc 2.2L DOHC H22A4 (VTEC) 16V (1998)

Wire Color Codes

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Prelude Type-SH L4-2157cc 2.2L DOHC H22A4 (VTEC) 16V (1998)

The following abbreviations are used to identify wire colors in the circuit schematics:

WHT White
YEL Yellow
BLK Black
BLU Blue
GRN Green
RED Red
ORN Orange
PNK Pink
BRN Brown
GRY Gray
PUR Purple

LT BLU Light BlueLT GRN Light Green

The wire insulation has one color or one color with another color stripe. The second color is the stripe.

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General Module: Diagnostic Aids

Five Step Troubleshooting

1. Verify The Complaint

Turn on all the components in the problem circuit to check the accuracy of the customer complaint. Note the symptoms. Do not begin disassemblyor testing until you have narrowed down the problem area.

2. Analyze The Schematic

Look up the schematic for the problem circuit. Determine how the circuit is supposed to work by tracing the current paths from the power sourcethrough the circuit components to ground. Also, trace circuits that share wiring with the problem circuit. The names of circuits that share the samefuse, ground, or switch, and so on, are referred to in each circuit schematic. Try to operate any shared circuits you didn't check in step 1. If theshared circuits work, the shared wiring is OK, and the cause must be in the wiring used only by the problem circuit. If several circuits fail at thesame time, the fuse or ground is a likely cause.
Based on the symptoms and your understanding of the circuit's operation, identify one or more possible causes.

3. Isolate The Problem By Testing The Circuit

Make circuit tests to check the diagnosis you made in step 2. Keep in mind that a logical, simple procedure is the key to efficient troubleshooting.Test for the most likely cause of failure first. Try to make tests at points that are easily accessible.

4. Fix The Problem

Once the specific problem is identified, make the repair. Be sure to use proper tools and safe procedures.

5. Make Sure The Circuit Works

Turn on all components in the repaired circuit in all modes to make sure you've fixed the entire problem. If the problem was a blown fuse, be sureto test all of the circuits on that fuse. Make sure no new problems turn up and the original problem does not recur.

Troubleshooting Precautions
Before Troubleshooting

1. Check the main fuse and the fuse box.2. Check the battery for damage, state of charge, and clean and tight connections.

CAUTION:

^ Do not quick-charge a battery unless the battery ground cable has been disconnected, or you will damage the alternator diodes.
^ Do not attempt to crank the engine with the ground cable disconnected or you will severely damage the wiring.

While You're Working

08798-9001

1. Make sure connectors are clean, and have no loose terminals or receptacles.2. Make sure multiple terminal connectors are packed with dielectric (silicone) grease. Part Number: .3. When connecting a connector, push it until it clicks into place.

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Prelude Type-SH L4-2157cc 2.2L DOHC H22A4 (VTEC) 16V (1998)

CAUTION:

^ Do not pull on the wires when disconnecting a connector. Pull only on the connector housings.
^

10-mega Ohm

Most circuits include solid-state devices. Test the voltages in these circuits only with a or higher impedance digital multimeter.Never use a test light or analog meter on circuits that contain solid-state devices. Damage to the devices may result.

Short to Ground With Self-Powered Test Light or DVOM

1. Remove the blown fuse and disconnect the battery and load.2. Connect one lead of a self-powered test light or (switched to the lowest "OHMS" range) to the fuse terminal onDigital Volt/Ohmmeter (DVOM)

the load side.

six inches

3. Connect the other lead to a known good ground.4. Beginning near the fuse box, wiggle the harness. Continue this at convenient points about apart while watching the test light or DVOM.5. If the self-powered test light goes on or the DVOM displays a low reading or no reading (ZERO), there is a short to ground in the wiring near that
point.

Testing For A Short to Ground With A Test Light or DVOM

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Prelude Type-SH L4-2157cc 2.2L DOHC H22A4 (VTEC) 16V (1998)

1. Remove the blown fuse and disconnect the load.2. Connect a test light or , switched to the appropriate DC Volts range, across the fuse terminals to make sureDigital Volt/Ohmmeter (DVOM)

voltage is present. You might have to turn the ignition switch to ; check the schematic to see.ON

six inches

3. Beginning near the fuse box, wiggle the harness. Continue this at convenient points about apart while watching the test light or DVOM.4. Where the test light goes , or the DVOM voltage drops to , there is a short to ground in the wiring near that point.OFF ZERO
Always use a DVOM on high impedance circuits. A test light may not glow (even with battery voltage present).NOTE:

Testing For a Short With a Short Circuit Locator (Short Finder)

1. Remove the blown fuse. Leave the battery connected.2. Connect the short finder across the battery terminals and the load (component) side of the fuse terminal.3. Close all switches in the circuit you're testing.4. Turn on the short finder. This creates a pulsing magnetic field around the wiring between the fuse box and the short.5. Beginning at the fuse box, slowly move the short finder along the circuit wiring. The meter will show current pulses through sheet metal and body
trim. As long as the meter is between the fuse and the short, the needle will move with each current pulse. Once you move the meter past the pointof the short, the needle will stop moving. Check the wiring and connectors in this area to locate the cause of the short.

Testing For Continuity

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Prelude Type-SH L4-2157cc 2.2L DOHC H22A4 (VTEC) 16V (1998)

When testing for continuity at a connector without wire seals, you do not have to separate the two halves of the connector. Instead, probe the connectorfrom the back. Always check both sides of the connector because dirty, corroded, and bent terminals can cause problems (no electrical contact = anopen).

Digital Volt/Ohmmeter (DVOM) "OHMS"

1. Disconnect the negative cable from the car battery. If you're using a , place it in the lowest range.2. Connect one lead of a self-powered test light or DVOM to one end of the part of the circuit you want to test.3. Connect the other lead to the other end.4. If the self-powered test light glows, there is continuity. If you're using a DVOM, a low reading or no reading (ZERO), means good continuity.

Testing For Voltage

When testing for voltage at a connector without wire seals, you do not have to separate the two halves of the connector. Instead, probe the connectorfrom the back. Always check both sides of the connector because dirty, corroded, and bent terminals can cause problems (no electrical contact = anopen).

1. Connect one lead of the test light to a known good ground, or, if you're using a , place it in the appropriate DCDigital Volt Ohmmeter (DVOM)

Volts range, and connect its negative lead to ground.

voltage.A loss of more than indicates a problem.one Volt

Always use a DVOM on high impedance circuits. A test light may not glow (even with battery voltage present).NOTE:

Testing For Voltage Drop

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Prelude Type-SH L4-2157cc 2.2L DOHC H22A4 (VTEC) 16V (1998)

2. Connect the other lead of the test light or DVOM to the point you want to check.3. If the test light glows, there is voltage present. If you're using a DVOM, note the voltage reading. It should be within of measured batteryone Volt

one Volt

Wires, connectors, and switches are designed to conduct current with a minimum loss of voltage. A voltage drop of more than indicates aproblem.

1. Place the in the appropriate DC Volts range. Connect the positive lead to the end of the wire (or to theDigital Volt/Ohmmeter (DVOM)

connector or switch) closest to the battery.

2. Connect the negative lead to the other end of the wire (or the other side of the connector or switch).3. Turn on the components in the circuit.4. The DVOM will show the difference in voltage between the two points. A difference, or drop, of more than indicates a problem. Checkone Volt

the circuit for loose, dirty, or bent terminals.

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> Relays and Modules > Relays and Modules - Accessories and Optional Equipment > General Module > Component Information > Description and Operation > Description

General Module: Description and OperationDescription

The multiplex control unit is composed of three control units (located in the driver's side kick panel, passenger's side kick panel, and driver's door).These three control units integrate the independent control units as usual and feature multiplex communication lines. The system reduces the number ofcontrol units and wire harness bulk, and improves the quality of electrical functions by means of the integrated circuits. This system has a built-inself-diagnosis function.

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General Module: Description and OperationSystem Functions

^

Multiplex Control System-

Multiplex function

- Wake up/sleep function

- Fail-safe function

-

Self-diagnosis functionMode 1: Self-diagnosis for the multiplex control system.Mode 2: Failure diagnosis for the input line of each system.

^

Integrated Control System-

Seat Belt Reminder Circuit

- Lights-on Reminder Circuit

- Key-in Reminder Circuit

- Engine Oil Pressure Indicator Flasher Circuit

^ Dash Lights Brightness Control
^ Entry Light Control System
^ Power Door Locks
^ Power Window
^ Wiper/Washer
^ Interlock System
^ Rear Window Defogger

MULTIPLEX COMMUNICATION SYSTEM

^Multiplex Communication Functions

To reduce the number of wire harnesses, digital signals are sent via shared multiplex communication lines rather than sending normal electricalsignals through individual wires.

^

The input signals from each switch are converted to digital signals at the central processing unit (CPU). The digital signals are sent from thetransmitter unit to the receiver unit as serial signals.
^ The transmitted signal is converted to a switch signal at the receiver unit, and it operates the related component.
^

There are exclusive communication lines between each of the multiplex control units:-

Door -> Driver's (from the door to the driver's multiplex control units) Wire color: BRN

- Driver's -> Passenger's (from the driver's to the passenger's multiplex control units) Wire color: LT GRN

- Passenger's -> Driver's (from the passenger's to the driver's multiplex control units) Wire color: PNK

^ The control units always communicate via these lines when the system is operating, and they stop communicating when the system is OFF.

^Wake-up and Sleep Functions

The multiplex control system has "wake-up" and "sleep" functions to decrease parasitic draw on the battery when the ignition switch is OFF.

^

In the sleep mode, the multiplex control unit stops the functions (communication and CPU control) when it is not necessary for the system tooperate.
^

As soon as any operation is done (for example, a door is unlocked), the related control unit in the sleep mode wakes up and begins to functionat once. This control unit also sends a wake-up signal to the other control units via the communication lines.
^

OFF 10 second

When the ignition switch is turned , there is about a delay before the control units go from the wake-up mode to the sleepmode.
^ If any door is open, the sleep mode will not function.

^Fail-safe Functions

To prevent improper operation, the multiplex control system has a fail-safe function. In the fail-safe mode, the output signal is fixed when anypart of the system malfunctions (for example, a faulty control unit or communication line).

^

Each control unit has a hardware fail-safe function that fixes the output signal when there is any CPU malfunction and a software fail-safefunction that ignores the signal from the malfunctioning control unit and allows the system to operate normally.

> Relays and Modules > Relays and Modules - Accessories and Optional Equipment > General Module > Component Information > Testing and Inspection > Symptom Related Diagnostic Procedures

General Module: Symptom Related Diagnostic Procedures

Faulty Communication Line Symptoms
Open in the line:

If the is an open in a communication line, most of the systems do not operate because one of the control units cannot wake up the other control units.But the control unit that is not awake can wake up by operating a switch related to the control unit.All of the control units wake up by turning the ignition switch (II).ON

Short in the line:

^ Most of the systems do not operate because one of the control units cannot wake up the other control units.^ The control unit can wake up by a related switch operation, but the other control units cannot wake up.^ All of the control units wake up by turning the ignition switch (II).ON

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General Module: Component Tests and General Diagnostics

Confirming The Function

1. Shifting to the sleep mode:

OFF

1. Turn the ignition switch .2. Cancel the key-off operation timer in the power window system by opening and closing one of the doors.3. Make sure that the exterior lights are off.4. If you do not operate the switches related to the multiplex control units more than after meeting the above conditions, the systemone minute

function shifts to the sleep mode.(All of the switches must be turned except door lock knob switches.)OFF

2. Confirming the sleep mode:

1. Check for voltage between the communication line.

There should be no voltage with the sleep mode ON.There should be standard voltage with the sleep mode OFF (see the voltage test table).

2. Check for voltage between each communication line and body ground while shifting to the sleep mode.

There should be no voltage.

3. Check the parasitic draw at the battery while shifting to the sleep mode. The ampere should change from about through to less than 70 80 mA
.10 mA

3. Confirming the wake up mode:

After confirming the sleep mode, turn the related switch ON, and wake up each control unit. If all of the operations works properly, the wake upmode is OK.(If any of the control units are faulty and cannot wake up, several parts of the system will not work at the same time.)

Multiplex Control System
Multiplex Control Unit (Door):

1. Remove the driver's door panel, and disconnect the 2OP connector from the door unit.

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Related Diagnostic Procedures > Page 41

Prelude Type-SH L4-2157cc 2.2L DOHC H22A4 (VTEC) 16V (1998)

2. Inspect the connector and socket terminals to be sure they are all making good contact.
^ If the terminals are bent, loose or corroded, repair them as necessary, and recheck the system.
^

If the terminals look OK, make the following input tests at the connector.-

If a test indicates a problem, find and correct the cause, then recheck the system.

- If all the input tests prove OK, the control unit (power window master switch) must be faulty; replace it.

Multiplex Control Unit (Passenger's):

1. Remove the right kick panel.2. Disconnect the 14P and 20P connectors, then remove the passenger's unit.

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Prelude Type-SH L4-2157cc 2.2L DOHC H22A4 (VTEC) 16V (1998)

3. Inspect the connector and socket terminals to be sure they are all making good contact.
^ If the terminals are bent, loose or corroded, repair them as necessary, and recheck the system.
^

If the terminals look OK, make the following input tests at the connector.-

If a test indicates a problem, find and correct the cause, then recheck the system.

- If all the input tests prove OK, the control unit must be faulty; replace it.

Multiplex Control Unit (Driver's):

1. Remove the under-dash fuse/relay box.2. Remove the driver's unit from the under-dash fuse/relay box.

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Prelude Type-SH L4-2157cc 2.2L DOHC H22A4 (VTEC) 16V (1998)

3. Inspect the connector and socket terminals to be sure they are all making good contact.
^ If the terminals are bent, loose or corroded, repair them as necessary, and recheck the system.
^

If the terminals look OK, make the following input tests at the connector and the fuse/relay box socket.-

If any test indicates a problem, find and correct the cause, then recheck the system.

- If all the input tests prove OK, the control unit must be faulty; replace it.

Self-Diagnosis Function (Mode 1)

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Prelude Type-SH L4-2157cc 2.2L DOHC H22A4 (VTEC) 16V (1998)

^

One second

after you go into self-diagnosis function mode 1, the function starts to indicate the diagnostic trouble code (DTC), and repeats theDTC every .three seconds

^

five ten seconds

From mode 1, disconnect the SCS service connector for to , then reconnect the SCS service connector, and the function goes frommode 1 to mode 2.

^ Make sure the ceiling light switch is in the middle position.

NOTE:

If no DTCs are indicated, but you know the system is abnormal, check these items:^

^ If only the lights or the buzzer indicates the DTC(s), the lights or buzzer is probably faulty.

Diagnostic Trouble Code (DTC) Table

The numbers in the table show the troubleshooting sequence.NOTE:

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Related Diagnostic Procedures > Page 45

Prelude Type-SH L4-2157cc 2.2L DOHC H22A4 (VTEC) 16V (1998)

If the lights do not come on and buzzer does not beep, check the continuity between the BLK wire of the multiplex control inspection connectorand body ground, and check the continuity between the LT BLU wire of the multiplex control inspection connector and multiplex control unit(driver's).

Communication Line Test

1. Continuity Test
Check for continuity according to the table.^

If there is continuity, go to step 2.

^ If there is no continuity, check for an open in the wire.

2. Voltage Test

A. Turn the ignition switch (II).ON

B. Check for voltage between communication line and ground:

The voltage should match the table in the image.

^

If the voltage is too high:A. Check for short to another wire.B. Check for poor contact at the connector on the receiver side unit.C. Faulty circuit in the receiver side unit.

^

If the voltage is too low:A. Check for short to ground or to another wire.B. Check for poor contact at the connector on the transmit side unit.C. Faulty circuit in the transmitter side unit.

If any control unit appears to be faulty, select one control unit, substitute a known-good control unit, then recheck. If the system works properly, theoriginal control unit is faulty; replace it. If there is still a malfunction, substitute a known-good control unit for another control unit, then recheck. If thesystem works properly, that control unit is faulty; replace it.

Self-Diagnosis Function (Mode 2)

1. Operate the switches as shown in mode 2.2. If the related circuit line of the switch is OK, the function indicates this by the ignition key light and ceiling light blinking once and the beeper
sounding once.

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Related Diagnostic Procedures > Page 46

Prelude Type-SH L4-2157cc 2.2L DOHC H22A4 (VTEC) 16V (1998)

five ten seconds

10 seconds

From mode 1, disconnect the SCS service connector from the multiplex control inspection connector for to , then reconnect the SCSservice connector again, and the function goes from mode 1 to mode 2.To cancel mode 2, disconnect the SCS service connector from the multiplex control inspection connector for more than or turn the ignitionswitch .OFF

If the line is faulty, there should be no indication. Refer to the tests for each system.NOTE:

Wake-Up Function Test
Description:

^

ON
ON

When the ignition switch is turned (II):When the ignition switch is (II), all of the multiplex control units wake up at the same time. In this case, the communication lines are notrelated for wake up function.

^

When a switch related to the multiplex control unit (door) is operated:First, the multiplex control unit (door) wakes up, then the control unit starts to communicate to the control unit (driver's). By this communication,the control unit (driver's) wakes up. The control unit (driver's) wakes the control unit (passenger's) up by the communication line, and all thecontrol units start to function.

^ When a switch related to the multiplex control unit (driver's or passenger's) is operated:

The control unit related to the operated switch wakes up, then the control unit wakes up the other unit. (In this case, the control unit (door) doesnot wake up.)

Related Switch (Input):

The switches and input signals that can wake up the multiplex control unit are shown:

Related Switch (Input) Table:

> Relays and Modules > Relays and Modules - Accessories and Optional Equipment > Keyless Entry Module > Component Information > Locations

> Relays and Modules > Relays and Modules - Accessories and Optional Equipment > Keyless Entry Module > Component Information > Locations > Page 50

> Relays and Modules > Relays and Modules - Accessories and Optional Equipment > Keyless Entry Module > Component Information > Locations > Page 51

Keyless Entry Module: Testing and Inspection

1. Remove the rear seat.2. Remove the left quarter trim panel.3. Disconnect the 8P connector from the keyless receiver unit.

4. Inspect the connector and socket terminals to be sure they are all making good contact.
^ If the terminals are bent, loose or corroded, repair them as necessary, and recheck the system.

^

If the terminals look OK, make the following input tests at the connector.-

If any test indicates a problem, find and correct the cause, then recheck the system.

- If all the input tests prove OK, the control unit must be faulty; replace it.

> Relays and Modules > Relays and Modules - Body and Frame > Door Lock Relay > Component Information > Diagrams

> Relays and Modules > Relays and Modules - Body and Frame > Door Lock Relay > Component Information > Diagrams > Page 56

Door Lock Relay: Testing and Inspection
Five-terminal type A:

1. Check for continuity between the terminals.
^ There should be continuity between the No.1 and No.2 terminals when power and ground are connected to the No.3 and No.5 terminals.
^ There should be continuity between the No.1 and No.4 terminals when power is disconnected.

^ Door lock relay

> Relays and Modules > Relays and Modules - Body and Frame > Keyless Entry Module > Component Information > Locations

> Relays and Modules > Relays and Modules - Body and Frame > Keyless Entry Module > Component Information > Locations > Page 60

> Relays and Modules > Relays and Modules - Body and Frame > Keyless Entry Module > Component Information > Locations > Page 61

Keyless Entry Module: Testing and Inspection

1. Remove the rear seat.2. Remove the left quarter trim panel.3. Disconnect the 8P connector from the keyless receiver unit.

4. Inspect the connector and socket terminals to be sure they are all making good contact.
^ If the terminals are bent, loose or corroded, repair them as necessary, and recheck the system.

^

If the terminals look OK, make the following input tests at the connector.-

If any test indicates a problem, find and correct the cause, then recheck the system.

- If all the input tests prove OK, the control unit must be faulty; replace it.

> Relays and Modules > Relays and Modules - Body and Frame > Power Door Lock Relay > Component Information > Locations

Power Door Lock Relay: Locations

Left Side Of Dash (Dealer Installed Option)

> Relays and Modules > Relays and Modules - Body and Frame > Power Door Lock Relay > Component Information > Locations > Page 65

Driver's Only Unlock Relay

> Relays and Modules > Relays and Modules - Body and Frame > Seat Heater Relay > Component Information > Locations

> Relays and Modules > Relays and Modules - Body and Frame > Seat Heater Relay > Component Information > Locations > Page 69

Seat Heater Relay: Testing and Inspection
Normally open type A:

1. Check for continuity between the terminals.
^ There should be continuity between the No. 1 and No.2 terminals when power and ground are connected to the No.3 and No.4 terminals.
^ There should be no continuity between the No.1 and No.2 terminals when power is disconnected.

^ Seat heater relay

Type 1:

Type 2:

> Relays and Modules > Relays and Modules - Body and Frame > Sunroof/Moonroof Relay <--> [Sunroof / Moonroof Relay] > Component Information > Locations > Alternate View

Dashboard

> Relays and Modules > Relays and Modules - Body and Frame > Sunroof/Moonroof Relay <--> [Sunroof / Moonroof Relay] > Component Information > Locations > Alternate View > Page 74

Sunroof/Moonroof Relay: LocationsPhoto

Moonroof Close Relay

Left Kick Panel Area

Moonroof Open Relay

> Relays and Modules > Relays and Modules - Body and Frame > Sunroof/Moonroof Relay <--> [Sunroof / Moonroof Relay] > Component Information > Locations >

Alternate View > Page 75

Prelude Type-SH L4-2157cc 2.2L DOHC H22A4 (VTEC) 16V (1998)

Left Kick Panel Area

> Relays and Modules > Relays and Modules - Body and Frame > Sunroof/Moonroof Relay <--> [Sunroof / Moonroof Relay] > Component Information > Locations > Page 76

Sunroof/Moonroof Relay: Testing and Inspection
Five-terminal type B:

1. Check for continuity between the terminals.
^ There should be continuity between the No.1 and No.2 terminals when power and ground are connected to the No.3 and No.5 terminals.
^ There should be continuity between the No.2 and No.4 terminals when power is disconnected.

^ Moonroof close relay

> Relays and Modules > Relays and Modules - Brakes and Traction Control > Brake Fluid Pump Relay > Component Information > Locations > ABS Pump Motor Relay

Brake Fluid Pump Relay: LocationsABS Pump Motor Relay

Under-hood Fuse/Relay Box