System 11 Club !

the Error message in audits means that that audit has failed its checksum the only connection to a bad diode would be if the diode was causing a reset at the precise moment the audit was updating. Start by replacing the diodes on your flipper coils, to test them you have to lift one side, so might as well just replace them. You might have other issues though, with the power supply chain. Might want to start a separate thread to get more indepth with the sys11 gurus here

https://www.marcospecialties.com/pinball-parts/LKA118

Most cam locks you buy have the correct sized square cutout, unless they are tubular key locks they usually have the smaller type. The ones that PBR sells are usually the 1382 key with the correct cam as well.

There's a plastic part that latches the fault, it might be worn and need to be replaced. I think the same or similar one is used on the fireplug in fire as well.

Nice how it's not really shown in the manual!

Pull them out read them in on an eprom burner and compare to files downloaded from ipdb/pps.

That's an IDC type connector, used by manufacturers for speed of installation (not longevity). Most people replace them with the crimp in type. (Me included).

If they aren't disturbed they're usually ok for a years, but once its time to replace them, they get the crimp type.

Crimper:
https://www.greatplainselectronics.com/proddetail.asp?prod=W-HT-1921

5 pin .100 connector housing:
https://www.greatplainselectronics.com/proddetail.asp?prod=22-01-2057

Pins:
https://www.greatplainselectronics.com/proddetail.asp?prod=08-52-0123

.062 connectors aren't used when mated to boards. (0.093 occasionally are, but 62/93 connectors are usually on wires inline to each other.)

Compare the connector you're replacing to the larger ones in the head on the boards to get the size. If it's the same as that you need .156 stuff also available at GPE and the same crimper will work. If it's .100 as you suspect, it will be smaller than those larger sizes. It's not clear from the manual and I don't recall what WW has as I sold mine several years ago.

Looks like old stock, probably fine if bought from reputable supplier

Sure, if the replacement post is long enough to take the washer and a nylock nut.

The only reason to not do this would be if it's a post that you might need to remove with some regularity, although I can't imagine what that would be.

The posts crack because the factory used the wrong loctite on them, once you replace the tnut you probably wont have this issue.