Fuses F601 and F602 on the audio/video board keep blowing; the siren spins, all inserts light solid, the aftermarket colour display stays dark and the game does not boot. With the AV board unplugged the game boots and a game can be started, but no coils fire, so the ball is never served.

Won't boot and AV board fuses F601/F602 blow: check solenoid fuses out of circuit

Cause: A blown solenoid fuse on the power driver board (missed when tested in circuit), plus two solenoid fuses of the wrong, higher rating. F601 and F602 feed the high voltage for an original plasma/DMD display and are not used when a colour LED display replaces it.

Checks

• Unplug the AV board and see whether the game boots, to split the fault.
• Pull every solenoid fuse and test each one out of circuit; compare each rating with the fuse list in the manual.
• Note that a fuse marked T in the manual is a slow-blow (time-delay) type.

Fix

• Replace the blown solenoid fuse and fit the ratings the manual lists (here 4 A where 5 A had been fitted).
• If an LED colour display is fitted, F601 and F602 can be left out (or the high-voltage connector unplugged), since the high voltage is not needed.

F601 and F602 protect the display high-voltage supply (about 100 V and more); power the game off before pulling them.

Systems

• WPC-95

Games

• Safe Cracker

Related tips

• WPC-95: regulated 12 V fuse F101 blows
• Flasher fuse F107 keeps blowing and a flasher transistor shorts: stray washer in a socket
• WPC-95 power driver board LEDs, test points and fuses
• F103 blows instantly: shorted ramp diverter coil; magnet fires the diverter if F104 open
• Dot matrix high voltage fuses F601 and F602

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