Changing batteries without losing settings

Steps

• Decide whether to keep settings: with the game powered off, a battery change returns it to factory settings and clears high scores.
• To keep them, change the batteries with the game switched on and running.
• Touch a grounded metal part first to discharge static.
• Fit the new cells one at a time with correct polarity, taking care not to short anything with tools or fingers.

Working inside a powered head: keep clear of the power supply and transformer, and touch only the battery holder.

Systems

• Williams System 3
• Williams System 4
• Williams System 6 / 6A
• Williams System 7
• Williams System 9
• Williams System 11
• Williams System 11A
• Williams System 11B
• Williams System 11C
• WPC Alpha-Numeric
• WPC Dot Matrix
• WPC Fliptronics
• WPC DCS
• WPC-Security (WPC-S)
• WPC-95
• Bally MPU AS-2518-17
• Bally MPU AS-2518-35
• Stern MPU-100
• Stern MPU-200
• Bally 6803
• Gottlieb System 1
• Gottlieb System 80
• Gottlieb System 80A
• Gottlieb System 80B
• Gottlieb System 3
• Data East CPU Version 1/2
• Data East CPU Version 3
• Data East/Sega CPU Version 3b
• Capcom

Related tips

• Changing the CPU batteries without losing settings
• Changing the CPU batteries without losing settings
• Move the batteries off the board
• High scores, replay levels or free play keep resetting
• New batteries but still losing settings: test the holder
• Battery power not reaching the RAM: diode D2
• Move the CPU batteries off the board
• Settings lost although the batteries are good (blocking diode D2)

Source: Pinball Machine Care & Maintenance, Bernard B. Kamoroff (Bell Springs Pinball Alley)