TH-50PX75
PCB Designation: P Board
Part #: ETXMM655MEHS
Symptom: No power, no relay clicks , no red LED.
Trouble shooting : check main fuses F601, F602 > OK > check voltage TP3- TP4 ( hot ground ) > 160 V >
Check D506 for short ( cold check with VOM ).
Cause: Shorted diode D506
Remedy: Replace D506
