One controlled insert never lights. The bulb, socket and wiring back to the lamp driver connector all test good, and a new SCR for that lamp makes no difference.
One controlled lamp dead even after a new SCR: lamp driver board fault
Cause: A fault on the lamp driver board itself, beyond the SCR. On this board the owner also found a broken trace.
Checks
- With the game on, briefly ground the output side of that lamp's SCR right at the SCR (not at the connector). If the lamp lights, the SCR or a trace is at fault.
- Inspect the board around that SCR and connector pin for cracked or broken traces.
- If LEDs are fitted, note the original lamp driver board needs modification to drive LEDs properly.
Fix
- Repair the broken trace with a jumper wire, or fit a replacement lamp driver board.
Systems
Games
Related tips
- One insert lamp dead after nearby work: bad pin in the lamp driver IDC connector
- One drop target lamp won't light after board work: broken wire in the harness
- Two inserts faintly lit all the time: failed lamp driver SCR
- Lamp driver board layout: SCRs, decoders and connectors
- Lamp driver board: which SCR drives which connector pin
- Some controlled lamps out: cold solder joint on the lamp driver board connector
- Substitute SCRs for the lamp driver board
- Controlled lamps flicker or stay out after fitting a replacement lamp driver with LEDs
Source: Pinball Repair help group!! (Facebook group)