I am currently working on a Harlem globe trotter pinball and the pop bumper solenoid randomly locks on and blows the fuse. It can either blow when the machine is turned on or after 2 - 3 hrs.
The pop bumper also has locked in attract mode approximately 15mins after the last game. All coils look to have the correct resistance and I cannot find any shorts.
Has anyone seen this before and have any advice on what I should be looking at. All the transistor on the driver board is ok and test correctly.