Issue: Client reports no 5VDC. Attempted to replace voltage regulator (U191), not completely installed. Fix: Removed U191, cleaned pins, and removed damaged pads. Re-installed U191 with jumpers where pads were removed, TP4 = 5.1VDC. Board passed general test (controlled lamps, solenoids, flashers, and GI).
Tag: Williams WPC
Issue: Client reports game resetting. Bench test of drive board shows the following voltages, all of which are OK. TP1 = 12.6VDC TP2 = 5VDC TP3 = 12VDC TP8 = 19.3VDC Fix: Suspect bad grounding connection in game (screws, connectors, etc.) – replaced BR2, C5, and Q1 (with improved ground connection) anyways.
Issue1: Settings reset, corroded batteries. Fix1: Replaced battery holder and batteries. Issue2: Diagnostic switches not working. Fix2: Cleaned switches with rubbing alcohol. Issue3: Trunk hits not registering. Fix3: Adjusted eddy current sensor under playfield. Issue4: Trunk shot not registering jackpots. Fix4: Adjust subway microswitch.