Sony KDS-50A2000 Training Manual page 41

The next step is to confirm application of the AC voltage to the G-Board
through the Main Fuse. Check for 110V AC at CN6001 on the G-Board to
confirm AC supply voltage. If the answer to the question diamond is No
(AC is not present at CN6001) then check all connections between AC
power cord and the G-board for loose connections or damage. Check
the main fuse (F6001) on the G-Board. Replace connectors, fuse, or
power cord if defective or damaged.
If the answer to the question diamond is Yes (AC is present at CN6001),
then the next step is to check if the Standby 5V power supply is functioning
properly. Check for Standby 5V at CN6005 on G-Board (Reference
Figure 2-5 for STBY 5V TP)). An alternative Standby 5V checkpoint is at
the Thermostat connector (or directly at the Thermostat) on the left rear
side of the TV (no need to remove any shields).
If the Standby 5V is present at the previously mentioned checkpoints
then the Standby 5V power supply is functioning, and there is a possible
microprocessor defect. In this case, replace the A1-Board.
If the Standby 5V is not present at the checkpoints then the Standby 5V
power supply is not functioning. In this case, replace the G-board.
TVP-23
Is AC 110 V
Present
at CN 6014 ?
Yes
Is voltage
Yes
5V
Present?
Is voltage
5V
Present?
No
4. Power Supply System
37