Issue: Game immediately tilts after feeding a ball to shooter lane.
Fix: Cut shorted capacitor on tilt bob (this capacitor is not needed for the tilt bob to function, but should be replaced for proper tilt sensitivity).
Bally Paragon
Williams System 11B CPU Board
Issue: No background music.
Fix: U42 (music control PIA) outputs test OK with Leon ROM but corrosion in area. Remove U41/42 PIAs, clean corrosion, and add sockets. No continuity from U42-16/17 to SRC3, fixed. Install new U41/42 PIAs. Remove U37 (LS138), clean corrosion, and add socket. Install new U37 chip.
Williams WPC Driver Board (Rottendog)
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).
Williams System 11 CPU Board
Issue: Client reports switch errors and solenoid issues. Diagnosis confirms bad special solenoid channels, bad switch input and control outputs.
Fix: Replace Q11 and Q12 with IRL530N.
Williams WPC Driver Board
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.
Stern Star Wars Premium
Issue: Gameplay issues. Fork ramp motor not working and fork ramp test not available in test menu, odd switch errors, etc.
Fix: Pro code installed, installed LE/Premium code from SternPinball.com
Stern Elvira House of Horrors
Issue: Crypt motor not cycling properly, getting stuck in some positions.
Fix: Secure topside plastic to the right of Crypt target causing binding and adjust crypt motor shaft position under playfield.
Bally Eight Ball Champ
Issue1: Won’t start a game.
Fix1: Tilt bob stuck closed.
Issue2: No sound.
Fix2: Bad volume pot, replace with resistor of reasonable value (no replacement pot on-hand)
Issue3: Some controlled lamps not working.
Fix3: Replace bad bulbs and one socket.
Williams Theater of Magic
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.
Williams High Speed
Issue1: No kickback.
Fix1: Clean mechanical assembly and adjust switch.
Issue2: Ball stuck in locks, won’t kick out.
Fix2: Replace bad fuse.
Issue3: Left flipper lane change not working.
Fix3: Fix end of stroke switch stack and fix reversed flipper pawl.