Electrical issues in my buddy's XJ

[kastein]

where are you actually located? NC? CT? If you are in the CT area like alex is, I may be down there sometime this week working on a YJ I'm swapping an XJ drivetrain+wiring into and can lend a hand troubleshooting. I'm an EE by trade and reasonably good at tracking down issues with XJ EFI systems.

 

[alex22]

The XJ in question is in the same town you picked up the welder in. Where are you working on the YJ?

 

[kastein]

At a friend's shop over in Newington. I'll let you know when I'm heading down that way, hopefully with a day or two of advance notice.

 

[rmx250cfl]

So it has been a long time since I updated this. Something finally fried, no longer runs, fuel pump doesn't kick on. At this point I have narrowed it down to the wiring harness most likely the power distribution center portion on the passenger side inner fender, OR the transmission control module... I'm willing to bet it won't be the easy one. Basically this jeep has had every sensor and electrical management part replaced in it. WTF MICE

 

[rmx250cfl]

UPDATE: replaced possible culprits, crank sensor, cam sensor, fuel pump, transmission control module. No luck. So now I'm in the process of replacing the wiring harness. I"ve already traced the old harness backwards and forwards and pretty much determined the issue is most likely in the pdc. Instead of chopping one out of another jeep I just went ahead and snagged the whole section, cleaned, dielectric greased and inspected backwards and forwards. Couldn't nock out the entire harness swap after a 14 hour workday but I made quite a bit of progress. Hopefully I'll have it put back together and "fingers crossed" running, this weekend.

 

[rmx250cfl]

I changed out the harness with the pdc in it. FIXED, finally. So now I have lots of spare parts and a jeep that runs great. Time for fun projects on it.

 

[rmx250cfl]

Went to get it ready for inspection, scanned it and had a bunch of pending codes, all evap, o2 sensors and neutral safety/ back up circuit. Replaced the #10 15a fuse on the passenger side kicker, changed out the evap canister purge valve. 100%, no codes, and my ac works now. Thanks everyone that gave their input and contributed to the repair of this beast. hopefully other people can read through this thread in the future and not go through the hassle I did to find a means to an end.

 

[smokinu]

actually this thread helped me track down a bad pcm as well! thanks