WPC flashers and coils all dead? Check the coin door interlock first
On later WPC games the coin door interlock switch cuts the high-voltage coil supply and the 20 V flasher supply whenever the door is open, so every flasher (and coil) looks dead. Close the door or pull out the interlock plunger before troubleshooting. If they are still dead with the door shut, measure AC between pins 1 and 4 of J102 on the power driver board: no AC there means the interlock switch or a connector between the transformer and the board; AC present points to the flasher fuse, the bridge rectifier (BR4 on many boards) or the traces after it.
Systems
Related tips
- WPC-95 LED102, LED103, LED104 or LED105 off
- WPC-95: all the 20 V coils dead, fuse good
- WPC-95: a dark +20 V LED at TP104 means the flasher supply is not leaving the board
- WPC-95 LED101 off (+5 V, game will not boot)
- Testing a WPC-95 rectifier diode
- +20 V filter capacitor C11 (C10 on WPC-95) blows apart
- WPC-95 driver board LEDs and test points
- Filter capacitors and GI triacs that fit WPC boards
Source: Pinball Repair help group!! (Facebook group)