Pharaoh
Williams, 1981The coil seems to test good on its own. Visually inspected for no broken wires. The switch associated with it is good. What do I troubleshoot next. I’d like to test transistors on the driver board but I can’t read a schematics well enough to know exactly where on the board to test.
Thanks
T
It's the hidden tomb shooter. Does not fire in the coil test.
I know where the solinoids section is on the driver board. I inspected all the connectors for broken or cracked solder points. I was going to try grounding out the coil directly and see if it fires?
Quoted from sd29travis:It's the hidden tomb shooter. Does not fire in the coil test.
I know where the solinoids section is on the driver board. I inspected all the connectors for broken or cracked solder points. I was going to try grounding out the coil directly and see if it fires?
It looks like a it's also controlled via a relay? Have you checked that?
Yes. I see that. I am a newbie will have to read up on how to test that relay. Any tips? Thanks for helping me out with this.
I took a look at the coil schedule, and it does appear the hidden tomb shooter is not activated from the driver board. The coil is directly activated from a switch on the playfield.
Here is the wiring diagram:
pharaoh shooter (resized).png
The first thing I see here is that there is an 8a fuse in line with the coil. I'm willing to bet a doughnut that this is one of those rare cases where williams put a fuse under the playfield near the coil in question. Check that fuse first. Then I would go investigating the switch shown just downstream of the coil.
That's good news it doesn't fire from the driver. There is a fuse beside it. I took it out and tested it. It's good. The switch that activates the shooter tests good in the diagnostics test. It registers the points and the sound cue when fired. I still need to figure out how to check the relay. It's the last thing in line that sends power to the coil. I don't know how exactly to test that.
That switch (8L7) is not part of the switch matrix. I is probably a heavy duty leave switch in line with the coil. That switch closes to ground.
I am not sure what roll the relay plays in powering up the coil. The wiring diagram is not real clear on that.
I don't think that is it. It has a diode attached to it, and the wiring diagram doesn't show one on the switch in question. The switch you are looking for is wired directly to the coil. There should be a diode on the coil with a white stripe on one end. Trace the wire from the coil starting on the end opposite from the white stripe. It should lead you to the switch you are looking for.
Quoted from uncivil_engineer:I don't think that is it. It has a diode attached to it, and the wiring diagram doesn't show one on the switch in question. The switch you are looking for is wired directly to the coil. There should be a diode on the coil with a white stripe on one end. Trace the wire from the coil starting on the end opposite from the white stripe. It should lead you to the switch you are looking for.
I had assumed that switch was in the relay.
Have you found the relay? Not sure how it's mounted from the schematics
Does the relay click or make any noise during coil test?
Looking at the schematic I was able to make more sense of it. The switch on the schematics mentioned above is definitely the one inside the relay. It switches the connection to ground to turn the kicker on. Do you have voltage at the fuse, and the lug of the coil connected to the fuse? You should still be able to fire the coil manually by grounding the lug that goes to the relay.
Dude I can tell you this gave me a headache once and know exactly what your issue is. There are two grounding wires in the backbox that ground on that screw. I'm betting your recently took it apart and put it back together and only have one ground wire attached.
Thanks guys. It seems to be working now. I bent that fat leaf contact under the coil arm to make better contact with the arm. If that's even what's supposed to happen?
And when I fired it in the test the coil functioned, and it and it works in the game. I don't quite understand what's happening there but it's working.
@nikpinball. I hear you man. I specifically remember thinking how easy it would be to forget both of those ground wires in the backbox. My machine was labeled luckily. They are there.
Ok, now the diagram makes more sense. Yes, you are correct, the switch in the relay.
I see now you got it to work. It sounds like you had a bad connection at the relay, and wiggling those wires may have fixed it.
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Rochester, NY