Maybe something unplugged toward the top right side of the MPU board. Can you post a picture of the board with the wiring?

Looks all connected. Did you do any work on the game before those pop bumper and shaker motor stopped working?

J19. Shouldn't there be a plug there for special solenoids?

Do the solenoids work in test mode?

Do they work if you ground out the transistor?

Sounds like some ground issue in my opinion. I always worry that shaker motor games are rattling the machine and creating future issues. I would also closely inspect and trace back the common from the pop bumpers and make sure there are no issues.

You are narrowing it down! Def not a switch issue since the switches work in test mode and I assume they count during game play.

So. You have power to the coils but the transistors ground the coil. So that leads me to believe you either have 3 bad transistors ( doubt it but possible) or possibly a chip problem.

Have you tried grounding the ground leg of the coil to a ground in the game to make sure it fires? I'm pretty sure it will.

I'm working on one as well this week. There was extensive acid damage and all but a string of GI was out. It has been sent off for refurbishment but I'm terrified of what I'll find when it's time to power up again. All that to say, following...

You said grounding the transistors don't fire the coils, but you can fire them manually from under the PF. That doesn't sound like an IC issue.

I know there's a fuse located under the playfield near the pop bumpers. Perhaps your cold solder joint is there, what with all the vibration in this area? It's certainly worth checking. Somewhat doubtful that includes the shaker motor, I'm honestly not sure.

Otherwise, check continuity between the connection points shown in the manual (below), as well as between the transistor tabs and coil lugs.

Bill

Earthshaker (resized).png

Beware that rotten dogs boards don't work well on the system 11s. I've tried several in differant games and the sound never works.

Have you check the connections at the board. According to the manual these are all in the same string. I'm guessing you have a cold solder joint somewhere on the board.

Screenshot_20180504-065816_Drive (resized).jpg

sound more like a connector problem,

Try grounding out at the connector plug (not at the transistor) for each one that's not working, if it worked at the coil it should work at the plug
possible broken wires somewhere, or bad connector.
Also test the mpu output at the connector, see if it's sending a ground signal out when the transistor is activated.

Do you have a jumper wire? Use it across the zero ohm resistors on the aux power supply with it in coil test. Do they fire now? If they do then replace them with a paper clip

I was just about to suggest the same thing. Have seen soooo many of those zero ohm ressistors go bad on system 11 boards. Especially aux power supply boards.

Replace all the zero ohm resistors on that board with wire and good to go. The other ones are not far behind the one that went.

Machine placed components

I still have a few tricks up my sleeve.

Grumpy has saved me a few times. He is a life saver!

Had the exact same issue.
Thanks guys for the heads up too.

It's is a real mind bender when diagnosing the game
with voltage on the Pop bumpers, and when you go to ground the transistors
the coil do not fire.
Grumpy Thanks for people like you out there to take time out to help!
another game fixed and money saved on board repair.
Post 3 years ago and still helping !
Thanks