Coils work in coil test ? Any switches stuck in switch test?

You cannot mess anything up running the test, audits or diagnostics, so don't worry about it.

Read through the manual to understand how the tests are run. There is a copy here if you don't have one: https://www.ipdb.org/machine.cgi?id=1338

The coil test fires all the coils sequentially so you will hear and likely see the results. Watch the display to know which one is firing or not, the manual will identify the location.

The switch test will cycle through and tell you which switches are activated on the display and with a pulse sound. Start the test with all the drops up and the balls out. There should be no switches activated, so nothing will be displayed. Then put the balls in the trough and you should show the two switches active. Then you can test all the others on the pf, using a ball instead of your finger is best.

Post detailed results and we can walk you through the rest.

Check to see if you have any blown fuses for the coils. If the game was acting erratically, maybe it fired all the coils at once and was enough to blow a fuse.

Go into test mode and see if what switches may be active. When you started a game, the scoring seemed like stuck switches.

Odd problem overall. Try replacing the 5101 RAM chip. I've had a couple where the game boots, but acts weird in game play. Usually, if the 5101 is bad, it won't let the game boot, but there are exceptions.

All the components on the circuit board are 40 years old, they can fail at any time regardless of the tech doing repairs. Did you verify none of the fuses were blown?

I had this problem was a fuse. Don't remember which one was a 2 amp i believe.