Samsung HCH551WX Service Manual page 25

Troubleshooting
4-3 No Power
Normal Normal
Check STB B+ Line (5V)
4-4 No Picture (Power ON, Raster and Sound OK)
4-2
Check CN805 pin 2 (STB B+)
Check CN501 pins 1,3,5
(See the waveforms)
Abnormal
Check Q212,Q213,Q214
Replae Q212,
Q213,Q214
Abnormal
Normal
Check CN805 pin 3
Check IC902
Abnormal
Normal
Check the circuitry
near IC201, IC202
Abnormal
Replace IC201,IC202
Abnormal
Check Q801 and Relay
Abnormal
Check the circuitry near
TDA6120Q and IC
Normal
Check
the digital board
Samsung Electronics