I've owned a WMS High Speed pinball for the past 15 years, and made a few simple repairs on it. However I've got some new problems and am not sure how to diagnose.

Issue #1: Left and right kickers (above the flippers) and the three jet bumpers fire perfectly during the diagnostic coil test, but only fire intermittently in-game. It's all or nothing in-game, and never a case where only one or two work. When they do work in-game, then they all work properly.

Issue #2: Speaker is intermittently failing. Again, it's an all or nothing deal, except that I can still hear the sounds faintly if I put my ear to the speaker. So I know all the sounds are activating properly, but the speaker is either failing or the power supply to it is failing.

Issue #3: I'm trying to identify what each fuse does, as I don't see this clearly documented in the original manual. Does anyone have a list of what each fuse supports?

Issue #4: I normally have the red spinning police light completely disconnected from the 4-pin connector. If I plug it in, it always spins + lights up and never stops. Is there some relay which could be permanently engaged and cause this to continuously run?

Thanks in advance for any help!

Thanks for the suggestions; I will start working through these.

Where is the volume pot located? I've never adjusted it before.

I found fuse F6 was open by checking it with my DMM. Replaced the fuse with a MDL 7, bit didn't notice any difference in behavior. What would be the impact of F6 not working?

Red and blue flashers seem to work pretty consistently even when the kickers and jet bumpers do not. I'll chase down the ground wire on the switches and see if I can find an issue.

I don't have a logic probe, just a DMM.

Thanks for the suggestion to look at 3J6. While inspecting pin 14, I noticed the entire 15-pin header block seemed loose, so I pushed it back into the power supply board. Now both the music and the 5 bumpers activate every time I turn on the machine or start a new game. Just a day or two ago the music was only 25% of the time, and the 5 bumpers were 0% of the time. So I think this solves issues #1-3. Awseome!

There is another intermittent issue which has been there for years. When the ball goes around both outlanes in a loop (from either left to right or right to left), sometimes the red and blue flashers don't fire. I always here the "honk-honk" sound effect however and scoring / extra ball advancement works as expected, so I know the switches are working properly to detect the travel of the ball around that upper loop. Could this be a ground problem on the flashers?

Thanks for the detailed help on the police light; I will try to debug that problem this week. It's never worked properly since I got the machine, but since the game works fine without it, I've just ignored it all this time.

OK, I did some testing on the two transistors you mentioned. Here is what I measured:

Q20 (top to bottom): 5V, 0.175V, 0V
Q24 (left to right): 0V, 24V, 0V

Picture of transistors mounted on the CPU board included for reference. Let me know if you have any thoughts on this, or if I need to collect more measurements.

For the red/blue flasher issue: I've played at least a half dozen games since I got the bumpers working again, and the flashers are still only firing maybe 2/3 of the time when the ball travels the outlane loop. They seem to always fire whenever there is some bigger event, like extra ball awarded, "you ran a red light", multi-ball, etc. It's only during that "honk honk" outlane loop that they first most of the time but not always.

High Speed CPU board (resized).png

I reconnected the 4-pin connector (actually only two wires in it, I suppose), and disconnected the 1J-11 header. Turned on the game, and the police light spins continuously in attract mode or during the game, same as before. Also, once I start a game, a ball won't launch with 1J-11 disconnected -- I assume this is expected.

I disconnected the grey wire from the square black relay, and yes the police light still activates and spins continuously when I power on the game.

I checked the wiring, and it matches your description. I will try getting a new relay to see if it resolves the issue. Thanks for all the help!

Sure enough, that relay was the problem. Super-easy fix -- wish I would have figured that out years ago! Anyway, nice to see the beacon spinning now when you "run the red light." All issues are now resolved. Thanks again for all the great help!