EFI or ECU relay clicking while rig is off???

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Switch replaced. Still clicking.
Sliding the key ever so slighly into the ignition makes it stop. That tells me the microswitch on the ignition lock is working.

It has to be in the ignition switch or lock...or at least that circuit.

The relay bench tests good.

FSM says it is ignition switch, relay or wiring harness issue. That leaves me with harness. Ugh.
 
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Can anyone tell me which (if any) of these terminals should have power with the truck off and key out of the ignition?

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This is the efi main relay socket.
I get power at 1 and 2 truck off.
If I pull the efi fuse it cuts power to 2 but I still have power to 1.
 
@medtro I know you know the 100 wiring well, and the EFI circuit really well. Without being able to put your hands on it, would you put your money on an issue the in the fuse box or should I be checking elsewhere?
 
I would run 2 new wires from the ignition switch to the EFI relay, or tap into other circuit for the trigger signal.
You just pre-emptively answered my question.
 
Curious to know how this turned out?
Bad ECU. I had to get one flashed. The part (used) was $100. Flash was something like $200. I was unable to diagnose it myself but ACC in Atlanta did amd took care of it.
The old ECU is in the landfill.

No issues since replacement but key programming was tricky.
 
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It’s been a bit rainy here and my symptoms returned. I have an unprogramed key that I have stuck in the ignition as a temp fix when it is parked. Not sure if it is the 8 dollar switch dying after two years or, more likely, a bad windshield replacement.
 

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