Hello, my first post.
I am working on a project for a family member, it is a 1996 XJ chassis and powertrain with a ****** truck body on it. I got the task of wiring up this project for which I was not involved with until now.
So, starting at the begining of connecting up circuits.
The cranking circuit is operational.
The ASD and Fuel relays will not energize. All the wiring is intact and correct. There is power in all the correct locations at the relays, however the relays will not pull in. they are not getting ground through the PCM at pin C3 for the ASD and C19 for fuel.
What does the PCM need to see for other I/O to close the grounds on those circuits? A lot of stuff is not hooked up yet. Or is there another way to trouble shoot this? I am pretty sure the PCM is not getting what it needs to activate those relays or the PCM is bad.
Any help is appreciated. Thank you
Billy.

 

I presume you have access to the '96 FSM, there is a link on here to download it free, you have to search the archives

There is a section that describes the order of operations for the ASD relay, what it needs to see, from memory there is 2 ground wires to the PCM for that circuit

look in the "Index" to find it, post up that section on here if you have it, I am to busy to do that atm sorry

 

If the ASD and Fuel relays won't energize and the PCM isn't providing ground, it's likely due to missing signals from other inputs and outputs. Double-check your connections and make sure everything's in order.

 

stupid question maybe, but has the OP checked for any stored codes?

 

Thanks for the feedback,
so i did manage to find a FSM and read a lot of helpful info.
apperently, with the key in run mode the ASD is pulsed for three seconds by the PCM. I was looking for constant energization. so when i look for the pulse it is there. so PCM is operational.
As for looking for other missing I/O, that was my question. I dont know what other I/O the PCM would be looking for but I know now.
Thanks guys.

 

the fuel pump should be able to be heard for that 3 seconds, when u turn the key to on, jump back and listen for its whir

If the PCM senses all is good, it will re-activate the ASD relay, if not, it wont

I believe there is a section, check the Index for "ASD relay", and it tells you what the conditions are