I bought this 91 DX (AT) in a rough electrical state. The previous owner was about half way through some audio upgrades - the wiring looks like a mess but at the time it cranked and ran fine. I let it sit over the winter and noooow, it won't crank or start. I'm a fair hand at mechanical work but this is the first time I've had to chase some real electrical demons.

Relevant details:

• When I bridge the starter solenoid directly off the battery it's cranks immediately. I'm pretty sure that means the ground, battery, and the starter itself are a-okay.
• When I put the key in, I hear the fuel pump prime and all my lights come on.
• I checked the two large copper strip fuses on the passenger side strut and they look fine.
• I checked the smaller fuse under the drivers side dash and it looks fine too.
• There are two boxes, that I think are relays and I can feel/hear them clicking when I turn the key

I did some research and the suggestions are all over the place. Here are the things I think I need to check. I'm looking for feedback on anything I missed or included erroneously and for tips on how to bridge the various possible failure points to isolate the problem.

• There are two relays that should be clicking. One to the left of the driver and underneath the dash and one to the right of the driver and underneath the dash.
• The AT has a neutral/park safety switch.
• The ignition switch proper.

Left side relay, I think


Right Side Relay, I think


Questions:
Are the relays involved in the starter circuit?
If so, are these the two relays?
How can I bridge these relays to test them?
How can I bridge the key switch to test it?
How can I bridge the neutral safety switch?
If the starter works when it's bridged, does that mean my grounds are fine?
Is there any other potential problem point that I've missed?

 

So I've studied the wiring diagrams and near as I can tell there are no relays at all in the startup circuit for 91s with A/T.




The battery power gets routed through two fuses, then to the ignition switch, then through the neutral safety switch, then to the starter solenoid, then through the ground back to the battery.
The starter motor and starter solenoid share the same ground, so if I can bridge-start the solenoid then the grounds have to be fine.

I've already checked the fuses, but I'll look again.
That means I need to learn how to bridge the ignition switch and the neutral safety switch.

Here's what I'm thinking.
1) Bridge them both at the same time. If it cranks then the wiring between the switches is fine. If it doesn't crank then there's a break in the wiring. My troubleshooting steps here assume that the switches are the problem. I'll revisit if I can't get it to crank by bridging the switches.
2) Un-bridge the ignition, leave the neutral safety switch bridged, try to crank the car. If it work then the problem is the neutral safety switch. If it doesn't crank then the problem is the ignition switch. Let's confirm it in the next step.
3) Unbridge the neutral safety switch, re-bridge the ignition. If it cranks then the problem is the ignition switch. If it still doesn't crank and bridging the starter solenoid directly still works theeeeen my understanding of the circuit is incorrect and it's time to beg for more help.

How to bridge. This part is more nebulous, based on the diagram I need to directly connect the white/black wire to the black/white wire. Hopefully they both use connectors and I can just bridge the pins with a paper clip or something.
Likewise for the neutral safety switch, I need to bridge the black/white wire, with the black/white wire. I'll review the switches after work, I don't recall what the wires/connectors look like off the top of my head.

 

Okay so I bridged the black/white wire at the neutral and then bridged the white wire to the black/white wire on the ignition. When I bridged the ignition, a relay, the one of the left in the above picture kicked in with a very weak click. Still no crank. There isn't a relay in A/T 91s sooo either I'm super wrong about that or this relay is part of some custom work the previous owner did. The schematic is on the relay, so I think I'll try bridging what I think are the two switch wires.



Looks like 87 and 87A are the wires that I want to bridge.



Nope still nothing. Now it's time to think some more.