El Dorado City of Gold (Gottlieb, 1984): Troubleshooting and System 80A Replacement Boards
Your El Dorado City of Gold by Gottlieb has scrambled displays, faulty drop targets, lamps flashing in unison, or no attract mode? These symptoms are typical of Gottlieb System 80A pinball machines whose original boards are now over 40 years old. The good news: our battery-free replacement boards, Plug & Play, bring your machine back to life.
El Dorado City of Gold (Gottlieb, 1984): Overview
Released in 1984, El Dorado City of Gold is a solid-state System 80A remake of the electromechanical classic, with a dynamic layout and numerous drop targets. It uses the Gottlieb System 80A electronics.
- Manufacturer: Gottlieb
- Year: 1984
- Electronic system: Gottlieb System 80A
- Type: solid state, drop targets
- Theme: city of gold / treasure-hunt adventure
Common Issues (System 80A)
All Gottlieb System 80A pinball machines share the same weaknesses as System 80, with added complexity from alphanumeric displays and speech synthesis:
- Leaking NiCad battery: soldered to the MPU board, it corrodes traces and components over time — the #1 cause of dead boards. Remove it immediately.
- Floating grounds: the original ground wiring is undersized and causes resets and erratic behavior. Ground mods are virtually mandatory.
- Edge connectors (the "Gottlieb plague"): oxidized edge connectors cause display faults, missing digits, and intermittent failures. Clean or replace them.
- Corroded connectors: Molex connectors, especially the MPU-to-driver connection, lose contact and require re-pinning.
- Drifting power supply: the 5V and 12V rails sag over time; trim pots and aging capacitors need attention.
- Sound board: leaking capacitors, cold solder joints, and failing ROMs cause weak or absent sound and speech.
El Dorado City of Gold-Specific Issues (Forum Reports)
- Scrambled displays + glitching audio: 1 or 2 digits per display scrambled and sound playing randomly — a board/connector-related symptom.
- Faulty drop targets: failure of one target or a whole bank of 5 points to a switch-matrix fault (e.g. switch #40 on the bank of 10, switch #11 on the bank of 5).
- Playfield lamps flashing in unison: for a few seconds up to a minute, then back to normal on the next game.
- No attract mode: check the ribbon cables, which are often worn.
- Battery damage on the CPU board: corrosion that must be neutralized.
Compatible Replacement Boards for El Dorado City of Gold
- GottFA80_Plus (Light) — all-in-one CPU + driver + power supply board, without sound.
- GottFA80_Plus (Full) — same all-in-one board with integrated sound.
- Gosof — replacement sound board for System 80 and 80A.
- Godri80 — replacement driver board.
- Lisy80 — CPU board + web-based diagnostics.
- GoPOP80 — pop bumper driver board (MA-922).
The GottFA80_Plus replaces the original CPU, driver, and power supply in a single board — battery-free, no corrosion risk. The Gosof replaces the sound board (System 80 and 80A, including speech synthesis). Installation is Plug & Play, with tutorials and free support. Contact us.
FAQ — El Dorado City of Gold Gottlieb
My displays are scrambled and the sound plays randomly.
This points to a board or connector fault. Clean the edge connectors and re-pin; a GottFA80_Plus stabilizes the MPU and displays.
A drop target or a whole bank isn't registering.
Check the switch matrix (e.g. switch #40 on the 10-bank, #11 on the 5-bank). On the logic side, a GottFA80_Plus stabilizes switch reading.
Is the GottFA80_Plus compatible with my Gottlieb System 80A?
Yes. The GottFA80_Plus covers System 80, 80A, and 80B. If in doubt, contact us.
Do I need to keep the original battery?
No. Our boards run without a battery and eliminate the #1 cause of corrosion.
How long does installation take?
Installation is Plug & Play: just a few minutes, no soldering required, with tutorials and free support.
Does a battery-free board retain settings and high scores?
Yes. Modern replacement boards use NVRAM: no battery, no corrosion, and settings are preserved when powered off.
Step-by-Step Diagnostics
- With power off, visual inspection: look for any signs of battery leakage or corrosion on the MPU of your El Dorado City of Gold; remove the NiCad battery if still present.
- Power supply: measure the 5V rail and verify it reaches the MPU (replace the drifting trim pot or re-solder the regulator if voltage sags).
- Grounds: apply ground mods between the boards (CPU, driver, power supply, sound).
- Connectors: re-pin oxidized Molex and edge connectors, especially the MPU-to-driver connection.
- Displays: never connect or disconnect a display while powered on; test with a known good display.
- Final test: verify startup, credits, solenoids, and displays; if needed, contact free support.
Useful Guides
- How much does pinball machine repair cost? A price guide
- How much is my pinball machine worth? Value and estimation
- Pinball machine leg sizes: the complete guide
- Which board for a Gottlieb System 80, 80A or 80B?
See Also
- Ice Fever (Gottlieb, 1985)
- The Games (Gottlieb, 1984)
- Alien Star (Gottlieb, 1984)
- Amazon Hunt (Gottlieb, 1983)
