G'day Pinsiders!

Love the information everyone shares on here! This is my first post, and I am hoping somebody has come across a similar issue to mine.
I am sorting through some issues on a Tommy the who pinball, and one problem that I have not yet resolved, is with the mirror continuously running up and down.
I have done the following checks,
- switch test/ both up and down show up as working correctly.
-I have looked at the contacts on the relay under the Playfield and reflowed the solder on this board
- I have tested the tip122 transistor at location Q25 on the CPU tested ok if an in circuit check is accurate?

The mirror starts running as soon as the machine is powered on, could the relay be the wrong type? Or is there something else I can test that causes this to be constantly powered?

Any help would be greatly appreciated.

Thank you

Thanks for your reply @Yeoldpinplayer,

Your reference link did explain some different testing procedures which helped.
Although the transistors are still testing within the correct range, around .5v on the flanking legs while performing a continuity test.
I did see a note here that stated a transistor could still be faulty even if it tests ok! I am thinking that maybe I should change out Q25 tip122 transistor anyhow, just to be sure. I don't have the exact transistor on hand, although I do have some new tip102 transistors here.
Am I correct in saying that these would be an upgrade to the original?

Whilst Reading through the schematics and owners manual, I noticed that in the mirror up and down test procedure instructions it stated that the relay is driven by Q23 on the CPU board? Although on the chart inside the back box it lists Q25 as the mirror relay driver? (Please see pictures below). Maybe the test procedure is just referring to the location Q23 group of transistors on the CPU board? Anyhow all of the transistors in this group tested good.

PXL_20201129_000449129 (resized).jpg

PXL_20201129_000705405 (resized).jpg

PXL_20201129_000920210 (resized).jpg

Well, after double checking everything again I decided to replace Q23 and Q25 tip122 constant power transistors just to rule those out.
But the mirror is still continuously running, the board has had some previous battery corrosion damage. Everything else on the game works as it should and the pia led is not in error state.

Would anyone know if there is anything else I should check before shotgunning any other parts on the board?
All transistors on the cpu board did test within the correct ranges..
I don't have a way of testing the ic chips, and from the schematics it appears that the next in line is one of the 7408 chips and then the pia 5f 6821 chip.

Any other ideas out there?

Cheers