Coil 50 V test point and circuit (WPC-S and earlier)
The coil supply has no LED. Measure it at TP6 against TP5: expect 50 to 70 V DC. Power enters on J102 pins 5,6 and 8,9, passes fuse F112, bridge BR3 and capacitor C8, then the coil fuses F103, F104, F105 and F102, out to J106 to J109. LED2 and LED3, when fitted, are line voltage sensors; LED2 is normally on and LED3 normally off, both flickering with the lamps.
Coil voltage is 50 to 70 V DC; keep the coin door switch and fingers clear of driver board terminals.
Systems
Related tips
- WPC-89/WPC-S driver board LEDs and test points
- Bridge rectifiers to use on WPC-S and earlier driver boards
- Bridge positions on WPC-S and earlier driver boards
- Driver board LED1 off: switch matrix 12 V missing (WPC-S and earlier)
- Driver board LED4 off and the game won't boot (WPC-S and earlier)
- Driver board LED5 off: flasher 20 V missing (WPC-S and earlier)
- Driver board LED6 off: lamp matrix 18 V missing (WPC-S and earlier)
- Testing a bridge rectifier out of circuit
Source: Repairing Williams/Bally WPC Pinball Games from 1990 to 1999, Part Three, Clay Harrell (pinrepair.com)