Akai LEA-19V07P, LEA-22V07P, LEA-24V07P Schematic

LEA-19V07P

LEA-22V07P

LEA-24V07P

Important Safety Instructions ---------------------------------------------------------------- 3

Basic Trouble Shooting ------------------------------------------------------------------------- 4

Main Board Trouble Shooting ----------------------------------------------------------------- 5

Main Board Circuit Diagram -------------------------------------------------------------------14

Panel Interface Pin Connection --------------------------------------------------------------25

General Trouble Shooting ----------------------------------------------------------------------33

Software Upgrading Methods -----------------------------------------------------------------

Important Safety Instructions

Observe all warnings and cautions

● All warning and cautions on the unit and in the User Manual must be observed closely.

Servicing

●

Non-qualified service personnel shall not open the cabinet for repairing.

Be sure to unplug the power cord from the outlet before cleaning and servicing.

Handing and Cleaning the Screen

●Do not push on or scratch with hard objects. Or throw anything at the screen. The

screen may be damaged.

●To remove dust from the screen surface, wipe gently with a clean, soft and cotton-free

dry cloth.

● Do not use any type of abrasive pad, alkaline/acid cleaner or strong solvent such as

alcohol, thinner or benzene etc, as the surface maybe impaired.

Replacement Parts

● Make sure that the replacement parts are specified by the manufacturer, or those parts

with the same characteristics and performance as the original parts. Use of unauthorized parts can result in fire, electrical shock or other danger.

●Upon completion of service or repair work, request the service technician to perform

safety checks to ensure that the unit is in proper operating condition.

Basic Trouble Shooting

Problem: Do not power on and no red indicator light.

Please check the output voltage of AC adaptor, the proper output should be DC12V.

●

● Please check the fuse on the Main Board if broken.

Problem: Do not power on, red indicator light at stand-by mode.

Please check whether the power supply has somewhere short circuit to ground or not?

●

● The EEPROM or Flash memory lose the software, upgrade again please.

Problem: Power on the unit, no display on the screen, but sound is ok.

Please check whether the backlight of LCD/LED panel is lighted or not.

●

● If no backlight, check the connection is reliable? And check whether LED driver board is ok or

not? If not, please replace the LED driver board.

● If the backlight works normal, but no display or no picture on the screen, please check whether

the power supply to the panel (+5V) is right or not? If not, need to check whether the switch transistor on the Main board is broken or not? Refer to Main Board Trouble Shooting and Circuit Diagram.

Problem: The remote controller doesn’t work.

Please check whether the connector from the Main board to Key board is reliable or not? Refer

●

to Main Board Circuit Diagram.

Problem: No sound.

Refer to Main Board Trouble Shooting: Audio Trouble.

●

Problem: Crackly noise

● When turn volume high up it vibrate the casing and make crackly noise, please check and add

more cotton flannels on the cabinet. And please check whether the speaker is damaged. If yes, please replace a new speaker.

Problem: TV can not search any channels.

● Refer to Main Board Trouble Shooting: Function Trouble.

Main Board Trouble Shooting

1、Power Supply Trouble

Check U4 for 1.2V

It s normal but

No.4 f

U7/

Check if pin No.4 f

U4/

E6 is d

Check E3 for 12V output ?

F1 damage or power supply Check E9 for 5V output

Check if U1,U2 for 3.3V

and U3 for 2.5V output?

Check the circuit

of U1,U2 ,U3

U4/ AIC2857GR8TR damage

output

L2/10μH is damaged or

false welding

It’s normal but

the voltage is

high

L13/10μHis

dama

ed or false

welding

It’s normal but the

voltage is high

’

the voltage is

Low

Check if pin

RT8269GSP is

false welding

or U7 is

damaged

E9 is damaged or the loader is

in short

circuit

It’s normal but

the voltage is

Low

AIC2857GR8TR is false welding

or U4 is damaged

amaged or the

loader is in short

circuit

2、Display Trouble（exceptional screen）

and connected tightly

Exceptional screen

Check if the cable is correct

Y N

Check if the LCD

panel is OK

Change LCD

Check if the output circuit from

U12 to the jack to panel are normal

Check the circuit of U12

Change or repair the damage

components in this part

Change the cable

for panel

3、Display Trouble （white screen）

supply is normal(depend on panel)

White screen

Check if the voltage of panel power

Is there voltage on grid of

Q8/WPM3407 can changed

CN4 is ill-connected

(is there voltage for panel)

or Q8 is damaged

Check if the I/O of U12 is damaged

(the 132th pin)

(12～0V or 5V~0)

Check if the circuit of Q9 normal?

Is there output signal

from U12

Change the LCD panel

U12 is illness

or the cable to panel

Q9 is damaged

4、

Display Trouble（black screen）

Check if the power supply

for inverter is normal

Black screen

Check if the voltage on

CN13/BLON is 5V

Repair the power supply

The inverter is damaged

Check the control circuit from

BLON to U12 or U12 is damaged

5、Audio Trouble（No sound)

Is normal

Check external

No Sound

Check if have audio signal

input

Check the set of volume, Mute is normal

Audio equipment

Check signal output on pin no. 4 & 6 of U13

Check power supply (>11V)on pin no. 7 of

U13/1517P

Check the voltage (>9.2V) on pin no.8

Of U13

Check the signal output on pin 64 &65 of U12

Does it has signal input on U12

Check the circuit from U12 to U13

Rest it

Check external

speaker

Repair the U13 power supply

Does Q26 has damage

And repair D60 or R257

6、Function Trouble（TV video）

cable do have signal

(

in this part

(

N Y

TV can’t search any

channel/no picture

Confirm if the RF

Check if T2-pin7 for 5V

Check external

signal source

Check if t1-pin9&10have data

Check the circuit

from T2-pin9&10 to

U12

and the power

supply for U12

Check if T2-pin5,6 has

data for I

Check if T2-pin2 for variational

voltage within 1.8V~4.3V

Change T2

Check the circuit

Check the I2C circuit

between T1-pin5,6

and 82,83)

Check the

power supply

circuit

+ 23 hidden pages