It almost sounds like the switch for the start button (the white button to the left of the coin door on the cabinet) might be stuck closed somehow. Can you get back into switch test? When it was displaying 3 before in the switch test--that's the number it will display in switch test if it detects the start button is being pushed.

Also, the start button is pushed to advance the values in audit mode, which would explain why the values were scrolling up on their own if that switch is stuck. Take a closer look at that switch, it may be stuck closed or could be shorting somehow.

Ahh, i gotcha. I misinterpreted the "3" as being the switch it was detecting in the switch test.

When you put the game into switch test, does it bring up a number for each different switch you activate? Test a few different switches, and also test the start switch and check that each switch displays a number (the numbers for each switch are listed in the switch matrix diagram). I would recommend removing the balls from the game and reset all drop targets so that you shouldn't have any switches closed when you start the switch test.

I think the player displays (or at least one of them) display the numbers in switch test that correspond with the switch(es) that are closed. Are those blank as well when you try closing any switches in switch test?

Can you send a pic of all the displays while the game is in switch test mode?

If you go to the audits menu, do the values still climb on their own? (when you go to 18 to set free play, for instance)

Sounds like the game isn't detecting any playfield switches at this point.

The next thing to do is isolate the problem to the playfield or the driver board in the backbox.

An easy way to do so: first, you'll need an alligator jumper (a wire with an alligator clip at either end). Put the game into diagnostic switch test as you've been doing. Next, open the backbox and disconnect the 2 connectors at the upper-right side of the driver board--2J2 and 2J3. Clip one end of the jumper to any male pin of 2J2. Touch any of the male pins on 2J3 with the other end of the jumper. If the driver board is ok, you should get a noise from the speaker and a number should appear in the ball-in-play display. If you touch a different pin, you should get a different number accompanied by a noise. If you don't get any response from the game while doing this test, the problem is on the driver board. If the test reveals a number in the ball-in-play display when you jumper the pins that way, then i would focus on the playfield wiring since that indicates the driver board is likely ok.

If you need further assistance, don't hesitate to ask! If you want to, post pics of your boards i can circle the connectors you need to remove for the test.

This is more than you'll need, but not a bad price: https://www.amazon.com/KAIWEETS-Electrical-Alligator-Connection-Experiment/dp/B07WQ21YMY/ref=mp_s_a_1_2

Don't know if you have any local electronics places, but if you do they likely will have something suitable.

Just to be sure: did you put the game into the switch test before using the jumper wire between column and row pins? The credit/match display should show "03" when it's in the switch test. (It will be the test after the coil test in diagnostics)

Make sure to try all the pin combinations, by which i mean clip the jumper on pin 1 of the column connector, then touch all 8 pins on the row connector (one at a time) with the other end of the jumper and pay attention for a sound accompanied by a number on the displays (the number should be different for each pairing of row and column pins).

Then take the jumper off pin 1 and clip it to column connector pin 2 and try the 8 row connector pins with the other end. Repeat till you've done them all. We want to see if you're able to get a response out of any, and if so--which ones work.