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Hello, my name I Dan. What all has been done so far to try and fix? Thanks
You should be seeing 12v when circuit is not grounded, if your seeing less then 12v that means there is a wiring problem. When PCM grounds brown/white wire voltage on control side of relay will drop to 0. If you ran new wire then monitor voltage at pin 86 during problem, if it drops below 11v you know there is a wiring/connection problem between relay and fuse. If good then monitor ground on pin 85.
Does code set instantly if reset?
Monitor power on pin 86 and ground on 85, that will give us a little more clear idea of what is going on. I think that is best place to start. Keep me updated, thanks.
Sounds good, I'll talk to you then. Thanks.
I'm not sure if backfeeding ground to PCM will allow vehicle to run, it is definitely worth a try. If anything you will know PCM is the problem if the relay stays engaged because right now it engages then disengages. Let me know how it goes or if you have more questions, thanks.
sounds good, thanks.
With PCM backfeed ground did voltage at pin 86 still go up and down?
I meant to say 85, sorry about that. If voltage was steady on 85 with wire backfeed to ground this proves wiring is good leaving PCM as the only possible problem. Let me know how it goes, thanks.
I'd assuming you were feeding pin 85 ground by backfeeding pin 3 at pcm?
If you connect to pin 3 at PCM this should keep pin 85 grounded, if not you know it is a wiring problem. If so then you know PCM is the problem. Let me know how it goes or if you have more questions, thanks.
There is a wire that runs from pin 3 of PCM to pin 85 of relay so wiring only pin 3 to ground should be the same as running 85 to ground assuming the wiring is good. Let me know if you have more questions, thanks.
I'm not sure what else could be missing, from tests we did we proved wiring is good. I'll open question up to see if someone else has some ideas. Next option would be running new wires between PCM and relay.