Laser Cue (Williams, 1984): common faults and System 7 replacement boards
Does your Williams Laser Cue stay stuck in audit mode, fail to boot, reset or have no sound? These symptoms are typical of Williams System 7 pinball machines, whose original boards (MPU, Driver, power supply) are now over 40 years old. The good news: the WillFA7 replacement board, Plug & Play and battery-free, brings your machine back to life.
Laser Cue (Williams, 1984): overview
Released in early 1984, Laser Cue is a Williams System 7 pinball machine on a futuristic billiards theme. It is one of the very last System 7 games, just before the move to System 9.
- Manufacturer: Williams
- Year: 1984
- Electronic system: Williams System 7
- Type: solid-state pinball
- Theme: billiards / futuristic pool

Common faults (System 7)
On Williams System 3 to 7, the recurring faults come from ageing: leaking NiCad battery on the MPU (corrosion, the No. 1 cause of dead boards), worn 40-pin MPU↔Driver connector (the best-known weak point), resets/reboots on a 5 V drop (power headers and connectors to be resoldered), tired power-supply capacitors, displays with missing segments, and a solenoid fuse that blows (slingshot or stuck bumper).
Issues specific to Laser Cue (forum feedback)
- Stuck in audit mode / on the diagnostics screen: very often the 5101 RAM to replace (inexpensive), to try first.
- Stuck coin-door switch: if it stays closed, you can't exit audit; check the switch and its wiring.
- 40-pin MPU↔Driver connector: to rebuild (trifurcon pins) on these System 7.
- Display power: broken disc capacitors affecting the -100 V for the displays.
- Leaking battery on the MPU: corrosion, the No. 1 cause of dead boards.
- No sound: System 7 sound board to be diagnosed.

Replacement boards compatible with Laser Cue
- WillFA7 — 2-in-1 board (MPU + Driver) compatible with System 3 to 7, System 7 included.

📚 Further reading: Guide: which board for a Williams System 3 to 7?
The WillFA7 replaces the original MPU and Driver board (boot-up, logic resets, battery-free memory and RAM, coil driving) and removes the fragile 40-pin ribbon as well as the dependence on the old 5101 RAM. The sound board and the display power must still be maintained separately; our support team will guide you.
Plug & Play installation, battery-free, free tutorials and support. Contact us.
FAQ — Laser Cue Williams
My Laser Cue stays stuck in audit mode.
Often a tired 5101 RAM (or a coin-door switch stuck closed). The WillFA7 replaces the MPU and its memory, removing this dependence.
My Laser Cue won't boot or resets.
A corroded original battery and worn 40-pin connector are the No. 1 causes. The WillFA7 replaces the MPU and Driver and boots without a battery.
Is the WillFA7 compatible with System 7?
Yes. It covers System 3 to 7, System 7 included, and drives the logic and coils.
Should I keep the original battery?
No. The WillFA7 works without a battery and removes the No. 1 cause of corrosion on System 7.
How long does it take to install a replacement board?
Installation is Plug & Play: a few minutes, no soldering, with tutorials and free support.
Does a battery-free board keep the settings and high scores?
Yes. Modern replacement boards use non-volatile memory: no more battery, no more corrosion, and the settings are kept when powered off.
Step-by-step diagnosis
- Powered off, visual inspection: look for any battery or corrosion trace on your Laser Cue's MPU; remove the NiCad battery if it is still present.
- Power supply: measure the 5 V and check it actually reaches the MPU and Driver (redo the power solder joints and connectors if the voltage drops); check the fuses.
- Grounds and power connectors: resolder the tired headers between the boards to eliminate resets and reboots.
- 40-pin MPU↔Driver connector: re-pin the oxidised link with trifurcon pins, the No. 1 weak point of Williams System 7.
- Displays: never plug or unplug a display while powered on; test with a known-good display.
- Final test: check boot-up, credits, coils and displays; reminder: the WillFA7 replaces the MPU and Driver and boots without a battery. If needed, contact our free support.
See also
- Black Knight (Williams, 1980)
- Defender (Williams, 1982)
- Joust (Williams, 1983)
- Star Light (Williams, 1984)