Bulbs in the controlled lamp sockets blow almost as soon as the game is turned on, while GI lamps are fine.

New controlled lamp bulbs blow at once: lamp and solenoid wires swapped at J1

Cause: A previous owner had swapped the feature lamp supply wire with the solenoid bus wire at J1 on the rectifier board, putting about 43 V DC on the lamp circuit.

Checks

• Measure the controlled lamp supply wire against ground; it should be the low lamp voltage, not solenoid voltage.
• Compare every J1 position with the schematic.

Fix

• Put the two wires back in their correct J1 positions.

With the wrong wiring the lamp circuit carries solenoid voltage; measure carefully.

Systems

• Stern MPU-200

Games

• Cheetah

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