Dpms Failure - Samsung SyncMaster CSH7839L Service Manual

7 Troubleshooting

7-1-2 DPMS Failure

Check signal source
H/V sync video level.
Make No H/V sync (power off
mode)
LED blinks
Yes
+12 V line off
Yes
Q654 Base driving voltage exists?
Yes
Q659 Gate driving
2
voltage exists?
Yes
Done
7-2
No
Check IC201 Pin 31.
No
Check IC201 Pin 1.
Check and replace Q655.
No
Check IC201 Pin 2.
Check and replace Q654.
No
Refer to 7-1-1 No Power Supply.
WAVEFORMS
56.4 V (T601, #7)
2
CH1 P-P = 56.4 V CH1 RMS = 9.18 V
CSH7839L/CSH9839L