After an apparent power surge the game made a strange noise, switched itself off and would not come back on, though something still hums. All fuses test good, and the 5 V test point (TP2) on the power driver board reads only about 1.6 V.

Won't start after a power surge, 5 V reads very low: failed C4 on the power driver board

Cause: Filter capacitor C4 in the 5 V supply on the power driver board had failed. A new 5 V regulator made no difference; the original regulator was fine.

Checks

• Measure the 5 V and 12 V test points on the power driver board with the other boards connected and then isolated.
• Check C4 and C5 in the 5 V section and the solder joints at J101.
• After a surge, also check the line filter and varistor in the cabinet power box, working from the wall socket inwards.

Fix

• Replace capacitor C4 (and any other failed filter capacitors) in the 5 V section.

The power driver board and cabinet power box carry line voltage and stored charge: unplug the game and let the capacitors discharge before working on them.

Systems

• WPC Fliptronics

Games

• The Addams Family

Related tips

• Shorted or open bridge rectifiers
• Voltages made by the WPC power driver board
• Supplies made on the WPC power driver board
• Driver board LED4 off and the game won't boot (WPC-S and earlier)
• Driver board LED1 off: switch matrix 12 V missing (WPC-S and earlier)
• WPC-89/WPC-S driver board LEDs and test points
• Driver board supply test points and normal readings
• WPC power driver bridge rectifiers and +5 V regulator

Source: Pinball Repair help group!! (Facebook group)