Troubleshooting - Philips 15PF9925/12S Service Manual

1. General Features
No. Symptom
1 Soft touch doesn't
function properly
2 Soft touch doesn't
function
3 No screen
4 Dark screen
5 Broken OSD display
2. PC Mode
No. Symptom
6 Screen noise
7 Screen position error
8 Color beat noise
3. TV and external input
No. Symptom
9 No sound
- Speaker
- Earphone
10 Video color beat noise

TROUBLESHOOTING

Cause
Defective speaker wire
and inverter wire
1) Broken components and
soldering of them
2) P101 connector error
Input error of inverter connector
P502 and Pin 21 connector
being slipped out
Cracked components and
soldering at tuner board
1) Defective LCD lamp
2) Defective inverter
3) Input error of inverter connector
Defective the font rom of IC501
Cause
Clock or phase being
not able to be adjusted
Screen position error
horizontally or vertically
Soldering AD converter
or making it short
Cause
Defective Reset IC of IC603
Defective MSP3400D of IC601
Defective B+(8V,5V) of IC604,605.
Earphone shield case being touched
Soldering IC301 and IC507
Check Point
1) Make some space between the speaker wire and
the Soft touch Board by sticking the speaker wire
to the guide hole of the cabinet.
2) Arrange working state of A1. Tape in the inverter wire
and correct working state of the Shield case.
1) Check Soft touch with eyes
Check and repair soldering
2) Check and repair the P101 connector
1) Bend the pin legs of P801 connector -> recheck them
2) Check and repair the IC801,802 SI4925
1) Check and fix P502 connector
2) Check and fix the components at P502 LCD module
and at main board.
3) Check Pin21.
1) Check and repair tuner board and main board
2) Solder Q403, Q402 and C153
1) Replace the inverter
2) Replace the LCD lamp
2) Check the connector input.
Check and replace the font rom of IC501
Check Point
1) Resettig is needed according to the video card of each
PC
2) Horizontal noise : adjust phase until no horizontal
noise occurres
3) Vertical noise : adjust clock in menu until no vertical
noise occurres
1) Play the Auto Configure in Menu.
2) Adjust horizontal and vertical position until the screen
displayes normally
Recheck adn repair AD9884
Check Point
1) Check volume and speaker
- Sound comes out only when being inputted into Audio
L/R
2) Check after replacing IC603
3) Replace IC601
4) Check and replace B+ of IC604,605.
Check the mould of shield and JA401, Replace shield case
Re-soldering