I got this here Road Kings and everything works great with the exception of the left slingshot and Im not sure what to check next....
The sling coil does not fire during gameplay or in coil test. It also still does not fire when grounding it out to the ground braid with a jumper wire.
Ive tested the coil and its good, 4.1 ohms same as the working right sling coil.
Getting correct power to the coil from the power board.
Continuity check shows good, no breaks in either coil wire from the coil to the boards.
The sling’s leaf switches are also not registering in switch test or game. Checked those wires for continuity all good. All other switches and coils on the game function as they should.
I dont understand why the coil wont fire at all with a jumper when it has power. Any advice would be greatly appreciated!

Thanks pinball plus. I checked the coil with the meter and it showed good, but I had already gone ahead and replaced it with a brand new one ( also tested) just in case and same results, no fire. The sling switches ( above playfield ) do not register at all in game or switch edge testing. The below playfield switch IS registering however.

Bumping this. Anyone got any ideas on what I should do next?

Ok thanks Grumpy. Ill get back to it here in a bit and report back.

Ok one thing ive found is with the game on, the right (working) sling coil shows 4.1 ohms.
The problem left sling shows 1.9 ohms. When trying to ground the left sling to get it to fire, i get a spark but the coil does not fire.
The left sling switches do not score points or register under any circumstances.

With the game off, both coils show 4.1 ohms. With the game on, the problem sling coil is 1.9 while the working sling coil stays at 4.1.
Is this of signifigance?

I just found this note in the game saying q74 is bad and needs to be replaced. Looking at the manual i believe q74 is rhe predriver for q75, which is the driver transistor for this left sling. Would q74 being bad prevent the coil from firing using the grounding method?
Also, coil did not fire using the test point. Thanks GRUMPY for all your help.

The note...

image (resized).jpg

One wire only. Here is a picture of the troublesome components. I tested that red wire for continuity to the board connector and it showed continuity, i guess checking for bad solder joint is next? Thanks again.

image (resized).jpg

Ok @Grumpy, will do. Just been handed a honeydew list so I will get back out there in an hour or so. Thank you.