Working on a really nice Gorgar. The F2 2 1/2 amp Solenoid fuse blows on power up. The trough solenoid kicks the ball into the trough and the fuse blows. Things I tried so far include:

-Change fuse
-Change solenoid bride rectifier
-Replaced mpu header pins
-Re-flowed driver board pins
-Checked all mpu transistors
-special solenoid IC's checked out of circuit.

Everything checks out fine. I'm a little stumped now. Any ideas on what else to check? Does anyone know which transistor controls the ball trough solenoid? This shoudn't kick when turning the game on.

Thanks for the info. Will check out Q15 tomorrow.

I have a funny feeling the mpu is locked. Even of the 2.5amp fuses is blown, I should get attract mode and the led's on the board should run correct?

OK so I have to get passed this lock up. Will do that first. Maybe that's what's causing my ball trough solenoid to engage and blow the fuse.

The issue was a bad 6821PIA which drives the solenoids on the driver board. Symptom was the F2 2 & 1/2 amp fuse would blow on power up and the
ball trough would eject the ball immediately. Check all driver transistors and pre-drivers with a meter first to ensure they are ok. If ok, your culprit is the
6821 circled in the attached photo. Hope this helps someone.

driver board (resized).png