My $500 WJ Grand Cherokee has turned into more of an issue than was originally expected. I finally got a new crank sensor in, only to find that it didn’t fix the non-start issue that literally all the forums agreed was a bad crank sensor.
However, in the course of investigating I think I found a possible explanation. This Jeep might have an aftermarket security system. The signs are subtle but present. First is the mass of non-factory wiring and fuses in the steering column (first picture), including this janky looking sensor ring around the key.
There’s also what looks like a horn bolted up under the hood that’s definitely not present in engine bay photos I can find online.
An aftermarket security system would totally explain the fact that my ECU doesn’t seem to be getting power, but there’s two things working against this theory.
1) I can’t find a control box. If it’s present, it’s hidden wayyyyy in the bowels of the dash
2) The battery harness is untouched, and not a rats nest of taps and splices like you expect from an aftermarket install
This also doesn’t explain the one (1) time I miraculously got this thing to start and run on its own, back before I had it trailered to my house. It’ll also try to start on starting fluid, but sounds like the timing is all jacked up and dies quickly. If the ECU had no power, shouldn’t it have no spark at all?
It’s possible the factory immobilizer system is bad but that doesn’t explain all that weird wiring I found.
So, Oppo, what do you think?