Caveman (Gottlieb, 1982): faults and System 80 replacement boards

June 28, 2026

Is your Gottlieb Caveman no longer starting, showing dead displays, an erratic video screen or random tilts? These symptoms are typical of Gottlieb System 80 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 the pinball part of your machine a second life.

Caveman (Gottlieb, 1982): overview

Released in September 1982, Caveman is the very first hybrid pinball machine combining a classic pinball and an integrated video game (a screen in the middle of the playfield). About 1,800 units. The pinball part is based on Gottlieb System 80 electronics, supplemented by a dedicated video I/O board.

Manufacturer: D. Gottlieb & Co.
Year: 1982
Electronic system: Gottlieb System 80 (+ dedicated video I/O board)
Type: hybrid pinball / video game (solid state), displays
Theme: prehistory / caveman

Gottlieb System 80 MPU board — Caveman — The MPU board runs the entire Gottlieb System 80.

Common faults (System 80)

Gottlieb System 80 machines mainly suffer from their inter-board connectors (CPU, Driver, power supply, sound) which oxidise and create intermittent faults (the no. 1 cause, to be repinned), poor grounds (ground mods at the transformer are strongly recommended), an ageing power supply (unstable 5 V / 12 V), cracked solder joints (notably on the CPU daughter card), blank displays if a single bit fails to pass from the MPU to the display, the sound board (corrosion of chip legs) and sometimes a leaking battery on the MPU.

Issues specific to Caveman (forum feedback)

Video I/O board, the game's weak point: faults most often caused by defective integrated circuits (ICs).
Boot blocked if the MPU does not communicate with the video board: the MPU does not complete its start-up cycle without this communication.
Screen displayed in German: default behaviour when the video board does not receive data from the MPU (via the lamp drivers).
Random tilts: often U4 on the I/O board (and a switch #16 error); the nearby bridge rectifiers and orange capacitors can also be the cause.
A3-J3 and A23-J2 connectors: check that each wire is properly seated in its place (a wire may have been put back in the wrong spot).
Rare video parts: the GTB-MA265 card cage and know-how on this video part are rare; a methodical diagnosis is essential.

Battery corrosion on a Gottlieb System 80 board — Caveman — Typical NiCad battery corrosion on System 80: the number-one fault to fix.

Replacement boards compatible with Caveman

GottFA80_Plus (Light) — all-in-one CPU + Driver + power supply board, no sound.
GottFA80_Plus (Full) — same with integrated sound board.
Gosof — replacement sound board (System 80 / 80A).
Godri80 — replacement Driver board.
Lisy80 — CPU board + web diagnostics.
GoPOP80 — bumper driver board (MA-922).

GottFA80 board for Gottlieb System 80 — Caveman — The GottFA80 board: battery-free replacement, Plug & Play installation.

📚 Further reading: Guide: which board for a Gottlieb System 80/80A/80B? · System 80B special

Note: these boards replace the System 80 pinball electronics (MPU, Driver, power supply, sound). The video part (I/O board) is specific to Caveman and is not covered by these products: for that, contact us. Plug & Play installation, battery-free, free support.

FAQ — Caveman Gottlieb

My Caveman stays stuck at start-up.
The MPU does not complete its cycle if it does not communicate with the video board: check this link and the connectors. On the pinball side, a GottFA80_Plus Light or Lisy80 replaces the MPU.

The video screen displays in German.
This is the default behaviour when the video board does not receive data from the MPU (via the lamp drivers); check this communication.

I get random tilts.
Often U4 on the I/O board, or the nearby bridge rectifiers and orange capacitors; on the pinball side, make the grounds and connectors reliable.

Do the replacement boards handle the video part?
No: they replace the System 80 pinball electronics. The video I/O board is specific to Caveman; contact us.

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

Power off, visual inspection: look for any battery residue or corrosion on the MPU of your Caveman; remove the NiCad battery if still present.
Power supply: measure the 5 V line and check it reaches the MPU (resolder 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 with the power on; test with a known-good display.
Final test: check boot, credits, coils and displays; if needed, contact the free support.