From cold, only the GI comes on. After 10 to 15 minutes the attract lamps start and then the display, and the game plays normally. Until it boots, the solenoids fire and hold, blowing several fuses.

Only GI for 10-15 minutes after power-on, coils lock on and blow fuses: weak 5 V supply

Cause: The 5 V logic supply is too low at power-on, most likely from aged filter capacitors (and possibly cracked joints) in the original power supply, so the CPU doesn't start and the solenoid blanking never engages.

Checks

• Measure the 5 V at the CPU board right after a cold power-on and again once it boots.
• Unplug the display to see if the game then boots sooner.
• Inspect the power supply's fuse clips and header joints.

Fix

• Rebuild the power supply with new capacitors and fuse clips, and reflow its joints, or fit a modern replacement supply.
• Until then, keep the coin door open at power-up (which cuts solenoid power) until the display and attract lamps come on.

The power supply carries line voltage on its input side; unplug the game before working on it.

Systems

• Data East/Sega CPU Version 3b

Games

• Maverick

Related tips

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• Maverick: CPU and display EPROM types and latest versions
• Maverick: game pauses 10 to 20 seconds after each drain
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• Three backbox bridges on 192x64 DMD games
• Adding jumper wires across DB1 and C11-C14 (520-5047-03)
• A coil has power but never fires
• Several bank-switched coils or flashers dead, or firing the wrong device

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