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).
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.
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).
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.
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.
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
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.
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.
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.
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.
