F-14 (system 11A): What could cause a coil to lock on with the mpu disconnected? Locks on immediately upon power up and will blow the fuse within 1.5 sec. It's the right center eject. Snubber board has been removed and inspected. Resistor is shot, like most, but relay seems to be ok (open b/w GND and COIL lugs). Coil diode was failed open, but this shouldn't lock it on, correct? Coil resistance is 4.2 ohms, which is proper (AE-23-800-11 coil). Scratching my head. I've got to be missing something on the snubber board? Nothing else in the circuit, right?

I tried that. Not sure if the gnd wire in the front of the cab was good, but showed open, however, I didn't get continuity from that wire from snubber to mpu. I'll double check my results. And thank you for all the help you provide us! All the old posts I research have a few names that always pop up to offer assistance...

I believe so. I thought I read that C-11232, -1, or -2 could all be used. Trying to find that. C-11232 is what was there.

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Nevermind. I misinterpreted the notes in the solenoid table.

Manual shows this coil should be "A" part of A/C relay. Mine shows its the "C" side?

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This is what I'm seeing for actual wiring...

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Bounced it off another F-14 and the wiring looks correct. I get my brain wires crossed between the a/c relay and the snubber board.

690 ohms between purple/green wire and ground.

Yeah, noticed that. Bought this at auction... It's mounted correctly now and still fires immediately at power up. Thanks tho!

Sorry, just getting back to this. A nice snowy day to work on pinball... D5 reads good. The 600 ohm reading I was getting was with the purple/green driver wire connected to the snubber board. After disconnecting (and starting to replace it), I realized it was measuring the resistance across the snubber relay coil to ground. I checked D5 and D13 (both sides of the a/c select relay) w/ wires disconnected (unnecessarily) and they read good. Grey/green wire from diode board to Q31 isn't shorted. +24V brown wire on snubber board is reading 150 ohms, same as on the other snubber boards. I don't really understand why a power wire would be grounded, although some of the snubber schematics show it tied in to the gnd pad. I'm gonna chase that, as it's all I've really got at this point. Hoping my logic isn't flawed...

I would assume the same thing. Purple green reads open when it's disconnected.

Correct. I think I'll power it up with the snubber board disconnected, ensuring the fuse doesn't blow. Then methodically reattach one lead at a time (w/ power off obviously).

Welp, not sure what I did, but it works... Cleaned off the diode board. Maybe that did it? Regardless, thanks for the help! I have a good understanding of the snubber boards and a/c relays now (at least for the next month). Pinsiders like Grumpy and Ken are great assets to the community.