Phoenix (Williams, 1978): faults and replacement boards System 4
Does your Williams Phoenix not finish its reset, keep a stuck coil, show partial lines or no longer start? These symptoms are typical of Williams System 4 pinball machines, whose original boards (MPU, Driver, power supply) are now over 40 years old. Good news: the WillFA7 replacement board, Plug & Play and battery-free, gives your machine a second life.
Phoenix (Williams, 1978): overview
Released in 1978, Phoenix is a Williams System 4 pinball machine themed around the legendary bird reborn from its ashes. A fast and well-liked title from the first solid state generation.
- Manufacturer: Williams
- Year: 1978
- Electronic system: Williams System 4
- Type: electronic pinball (solid state)
- Theme: phoenix / mythology
Common faults (System 4)
On Williams System 3 to 7, recurring faults come from ageing: leaking NiCad battery on the MPU (corrosion, the No. 1 cause of dead boards), connectors that overheat or burn (power supply) and cracked connector solder joints, resets/reboots on a 5 V drop (power supply and MPU headers needing resoldering), rectifier bridge failing short (Williams put no fuse between transformer and bridge), displays with missing segments or digits (connectors to clean), and 28 V solenoid fuse blowing (stuck slingshot).
Issues specific to Phoenix (forum feedback)
- Reset that does not finish: the game stops in the middle of the start-up sequence without ejecting a ball; switch 7 of DS1 lets you restore the factory settings.
- Right slingshot coil stuck: often a faulty diode on the coil, plus the pre-driver and the driver on the Driver board (2N4401 and TIP102).
- Missing display lines: players 1 and 2 and the master display, intermittently — clean and reseat the connectors.
- Drop targets that do not reset: and multipliers (2X, 3X, 4X) that do not light up during the game.
- NiCad battery on the MPU: corrosion to be absolutely neutralised.
Replacement boards compatible with Phoenix
- WillFA7 — 2-in-1 board (MPU + Driver) compatible with System 3 to 7, System 7 included.
The WillFA7 replaces the original MPU and Driver board (start-up, logic resets, coil drive, battery-free memory). Purely power-supply faults (rectifier bridge, power connectors) still need to be addressed on the power supply side; our support guides you.
Plug & Play installation, battery-free, tutorials and free support. Contact us.
FAQ — Phoenix Williams
My Phoenix does not finish its reset.
Try a factory restore (switch 7 of DS1). If the MPU is worn, the WillFA7 replaces MPU and Driver and makes start-up reliable.
My right slingshot stays stuck.
Check the coil diode and the transistors (2N4401/TIP102). The WillFA7 replaces the faulty Driver stage.
Display lines are missing.
Clean and reseat the display connectors. A replacement MPU then makes the drive reliable.
Should I keep the original battery?
No. The WillFA7 works without a battery and removes the No. 1 cause of corrosion on System 4.
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 or corrosion trace on the MPU of your Phoenix; remove the NiCad battery if it is still present.
- Power supply: check the 5 V and the fuses; resolder the power-supply and MPU headers if the voltage drops or the game resets.
- Connectors: re-pin the oxidised Molex connectors, especially the MPU↔Driver link.
- Coils: check the solenoid fuses and the switches (stuck slingshot) before powering back on.
- Displays: never plug or unplug a display while powered; test with a known-good display.
- Final test: check start-up, credits, coils and displays; remember that the WillFA7 replaces MPU + Driver. If needed, contact free support.
See also
- Lucky Seven (Williams, 1978)
- World Cup (Williams, 1978)
- Contact (Williams, 1978)
- Disco Fever (Williams, 1978)
Sources & further reading
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