Some individual controlled (feature) lamps stay dark although the bulbs are known good.
Individual controlled lamps dead with good bulbs: dirty backbox harness connector
Cause: Their wires loop through the backbox insert harness, and the connector between the cabinet and backbox harness had oxidised contacts.
Checks
- Trace the dark lamps' wires back to the lamp driver board and note every connector they pass through, including the backbox insert harness.
- Unplug and reseat those connectors several times, and check for flattened or dirty contacts.
Fix
- Clean the connector contacts and reseat the harness connector (repin if the pins are worn).
Systems
Games
Related tips
- Replace IDC connectors on Firepower and later with crimp
- Features misbehave with the backbox ground strap loose
- All controlled lamps out: bad spade connections on the bridge rectifier
- Boards pass on the bench with Leon's code but the game is dead
Source: Pinball Repair help group!! (Facebook group)