Mr. Pinball Tip:

If your Williams System 3-7 starts up in audit mode that you can't clear by turning on & off, it may be your CMOS chip or battery. Test battery voltage at pin 8 and 22 on the CMOS. The voltage should be is over 3. If not, then change the batteries. If over 3, then the CMOS is bad. This is true even if the MPU self test comes up ok, as this may be a false reading.

John Nortum
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