Looks like it's one of the big TIP36C transistors ultimately controlling the ball launcher coil (if I'm reading this correctly). It's the one at Q5 on the PPB board on the schematic here, just follow the line from the bottom of the ball launch coil to the transistor at Q5:
942664430.png

To confirm we're looking at the correct circuit, can you verify you have an violet/orange wire on the non-banded lug on the ball launch coil? The banded side of the coil should have a yellow/violet wire.

Note that whether or not the TIP36C is bad, there are other transistors that work in conjunction with it--a TIP122 and a smaller 2N4401 pre-driver transistor. They're located in this region of the cpu board:
1926678481.png

I've read that if there's problem with any of the 3 transistors in one of these coils circuits, all 3 should be replaced at the same time (and the diode on the coil for good measure).

So I'd find the 2 transistors for coil 3 (I'm guessing it's coil 3 from the marking "3L" on the schematic with the coil on it, but i might be wrong ) on the CPU board and check them in addition to Q5 on the PPB board.

I'll admit these schematics are very difficult to follow, so you'll want to study then carefully to make sure we're checking the correct components.

Yep, GPE should have them all. You'll need TIP102, 2N4401, and TIP36C transistors. Also Stock up on a few spares of each just in case. Also get more fuses if you need them! I double checked the schematic, and I'm pretty sure i have it right--the ball launcher is solenoid 3. So Q5 on the PPB board (which actually fires solenoid 3/ball launcher) is driven by a TIP122 at Q44, which is pre-driven by a 2N4401 at Q36 (both of which are on the CPU board). Here's the page i found that info on, from the CPU board schematic:

1275618755.png

You'll also want to test the resistor array for that circuit as well. It's basically a long skinny package of resistors you'll find somewhere near the transistors on the cpu. See it here on the chart, labeled RA26: 128459597.png

One of the pins at one end of the resistor array will have a marking, usually a box or something to differentiate it from the other end--that's the common pin. You set your meter to test ohms and check for approx 2.7k ohms between the common pin and each other pin on the array. Like 1 probe on common pin, other probe on pin 2--take reading. 1 probe on common pin, other probe on pin 3--take reading, etc etc. Each pair should test close to 2.7k ohms--if they don't you may have found the underlying cause of the issue.

RA26 is here on the CPU board, above and to the right of CN11. Notice the square at the top of RA26? That's indicating the common pin i mentioned above, so one probe will be on that pin for measuring all 8 resistors on the array:

240653238.png

Here's the resistor array if you need one:
https://www.greatplainselectronics.com/proddetail.asp?prod=4610X-101-272

The transistors you might need would be: TIP102, 2N4401, and TIP36C. You can use GPE's search bar to locate them--you shouldn't have any trouble finding them. I wouldn't just go replacing all those parts just yet though--I'd try to narrow down which one(s) are the culprit first. Pinwiki has the procedures for testing each of the different transistors, and you can follow my instructions on the previous post about testing the resistor array.

Any update on this?

Couldn't hurt to get one, though it may not be necessary. Have you checked resistance on the coil? Have you tried removing the coil sleeve from it? If it's really difficult to remove, the coil is likely melted a bit. If there's a diode on the coil, I'd recommend replacing it before putting everything back together (or the new coil will have one installed if applicable)...

Did you get the other parts in?

Looks like i already listed them a while back

Looks like it should be this one, according to service bulletin #63 for GNR. https://www.marcospecialties.com/pinball-parts/090-5023-0B

It's listed in the bulletin as a 22-600 coil, part # 090-5023-01