One or more 555 bulbs on a small playfield lamp board stay dark.
Lamps on a plug-in lamp board do not light
Cause: The solder joints on the Molex header pins on the back of the lamp board have cracked from age and vibration.
Checks
- Inspect the header pin joints on the socket side of the board for rings or cracks.
Fix
- Reflow the header pin solder joints, then check the board-mounted lamp diodes.
Systems
Related tips
- One controlled lamp never lights, bulb is good
- A single lamp is out: the usual causes
- Bulb spares: #44 for CPU lamps, #47 for general illumination
- A group of general illumination lamps is out
- One string of GI lamps very dim: replace the bad GI wiring
- One insert stays dark with good bulbs and sockets: failed diode on its lamp board
- A group of clock lamps never light with good wiring: reseat the bulbs in their sockets
- General illumination dead or dim
Source: Repairing DataEast 1987 (Laser War) to Sega 1995 (Batman Forever), Part Three, Clay Harrell (pinrepair.com)