Bad Girls (Gottlieb, 1988): faults and System 80B replacement boards

June 25, 2026

On your Gottlieb Bad Girls, are some auxiliary board coils not firing, do you have no sound, are the drop targets misbehaving or is the game resetting? These symptoms are typical of Gottlieb System 80B pinball machines, whose original boards (MPU, Driver, power supply, sound) are now over 40 years old. Good news: modern replacement boards, Plug & Play and battery-free, give your machine a second life.

Bad Girls (Gottlieb, 1988): overview

Released in 1988, Bad Girls is a System 80B pinball machine with an offbeat theme of female outlaws in a western setting. It features the series' alphanumeric displays.

Manufacturer: D. Gottlieb & Co.
Year: 1988
Electronic system: Gottlieb System 80B
Type: solid-state pinball machine, alphanumeric displays
Theme: western / outlaws

Gottlieb System 80B boards — Bad Girls — The CPU and Driver boards of the Gottlieb System 80B.

Common faults (System 80B)

System 80B machines use alphanumeric displays and an MPU with battery-backed 5101 RAM. Recurring faults include: a leaking battery on the MPU (corrosion and loss of the 5101 memory), unstable power supply (the original trim pot struggles to hold 5 V and 12 V), cracked solder joints (particularly on the CPU daughter card), inter-board connectors that need re-pinning, poor grounds (ground mods essential), dead displays if a single bit fails to pass from the MPU to the display, and start-up disrupted by the fluorescent tube starter in the backbox.

Bad Girls specific issues (forum feedback)

Temperamental drop targets (3/11): the target drops at the start button and the whole bank resets with the "8 ball" target; if the 3/11 is hit first, everything works.
No sound: LED on the MA-886 sound board flashing; reflow the MA-1033 auxiliary sound board and check the ribbon cable.
Auxiliary transistor board coils not firing: grounding the transistors on the main Driver board confirms the coils are good.
"Phantom" problems: solved by replacing the entire interconnect cable.
Battery corrosion + bumper boards: clean the battery and resolder the pins on the pop bumper boards.

Battery corrosion on Gottlieb System 80B board — Bad Girls — Typical corrosion from a leaking battery on System 80B: neutralise it first.

Replacement boards compatible with Bad Girls

GottFA80_Plus (Light) — all-in-one CPU + Driver + power supply board, without sound.
GottFA80_Plus (Full) — same with integrated sound board (80B audio limited to a few titles).
Gosof — replacement sound board for System 80 and 80A (80B support currently limited to a few titles).
Godri80 — replacement Driver board.
Lisy80 — CPU board + web diagnostics.
GoPOP80 — bumper driver board (MA-922).

GottFA80_Plus board for Gottlieb System 80B — Bad Girls — The GottFA80_Plus: all-in-one board (CPU + Driver + power supply), battery-free.

System 80B note: favour the GottFA80_Plus Light — the 80B is covered on the CPU/MPU side. On the audio side, support is currently limited to a few titles (Bounty Hunter, Chicago Cubs Triple Play, Tag Team); for other System 80B games, keep and repair the original sound board and contact us (an audio solution is in the works).

Plug & Play installation, battery-free, tutorials and free support. Contact us.

FAQ — Bad Girls Gottlieb

My drop targets behave strangely at start.
This is a knockdown coil and bank switch fault. Check them; a new Driver board makes the control reliable.

I have no sound.
Is the LED on the MA-886 flashing? Reflow the MA-1033 auxiliary sound board and check the ribbon cable; repair the original sound board. For 80B audio, support is limited to a few titles — contact us.

Some aux board coils won't fire.
Ground the transistors on the main Driver board to confirm the coils, then replace the faulty Driver stage with a Godri80.

What about 80B sound?
Audio support is currently limited to a few titles (Bounty Hunter, Chicago Cubs Triple Play, Tag Team). For Bad Girls, keep and repair the original sound board and contact us; a solution is in the works.

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 the MPU of your Bad Girls; remove the NiCad battery if still present.
Power supply: measure the 5 V and check it reaches the MPU (redo the solder of the regulator or Q1 if the voltage drops).
Grounds: apply the "ground mods" between the boards (CPU, Driver, power supply, sound).
Connectors: re-pin the oxidised Molex connectors, especially the MPU↔Driver link.
Displays: never plug or unplug a display while powered; test with a known-good display.
Final test: check start-up, credits, coils and displays; if needed, contact the free support.