Samsung PS42D51SX/XEC Service Manual page 103

Circuit Description
■ Troubleshooting the Drive Board
1) Y Buffer
- To check whether the Y Main board is properly working, check the operation of the Y Buffer first.
- Separate the connector of the Y Buffer from the Y Main board
- Check OUTL and OUTH and confirm that the forward voltage reduction is between 0.4V ~ 0.5V.
UP - CN5407 1~10pin - OUTH / 11~33pin - OUTL
LOW - CN5507 50~41pin - OUTH / 40~17pin - OUTL
- In addition, the resistance between the points must be higher than a few kΩ .
13-18
OUTL OUTH
OU T L ( 5 ~ 2 4 )
CN5504
OU L H (1 ~ 4 )
Y - B u f f e r (L o w )
OU T L ( 3 5 ~ 3 8 )
OU T L ( 1 7 ~ 3 4 )
CN5404
Y - B u f f e r (U P )
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