LG L1510S, LB500J-EL TROUBLESHOOTING GUIDE

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TROUBLESHOOTING GUIDE

1. NO POWER

CHECK U803.

CHECK

U501 PIN 8

VOLTAGE

(5V) ?

NO

NO POWER

(POWER INDICATOR OFF)

CHECK POWER

BOARD, AND FIND

OUT A SHORT POINT

AS OPENING

EACH POWER LINE

CHECK J707

VOLTAGE

PIN1&PIN2(12V)

PIN4(5V)?

NO

CHECK 5VS LINE

(OPEN CHECK)

CHECK

U805 Voltage

(5V) ?

NO

CHECK IIC LINE

CONNECTION

(U501, U502)

CHECK U201 VCC,

XTAL, RESET

IS U201 PIN12

VOLTAGE REPEATED

AS PULSE SHAPE ?

NO

YES

YES

YES

NO PROBLEM

NO

CHECK KEY CONTROL

CONNECTOR ROUTINE

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2. NO RASTER (OSD IS NOT DISPLAYED) – INVERTER

CHECK MICOM INV

ON/OFF PORT.

J705 PIN8

5V?

NO

NO RASTER

(OSD IS NOT DISPLAYED)

CHECK POWER BOARD

J705 PIN1

12V?

NO

1. CONFIRM BRIGHTNESS
OSD CONTRL STATE.

2. CHECK MICOM DIM-ADJ
PORT

J705 PIN7

5V?

NO

REPLACE

INVERTER ASS’Y

CHECK

PULSE AS

CONTACTING SCOPE

PROBE TO CAUTION LABEL.

(CONTACT PROBE TO

CAUTION LABEL.

CAN YOU SEE PULSE

AT YOUR

SCOPE?

NO

REPLACE CCFL LAMP

IN THE LCD MODULE

YES

YES

YES

YES