Alright- Put in a new magnaflow CAT a few days ago. New downstream 02 Sensor (Bosch, whoops) and a new Muffler. Did the recommended break in for the CAT in the drive-way, then drove around a mile or so to see if any lights came on. Everything was quiet and the jeep was driving great. Parked it, and sanded it for paint prep (not relevant now). After sanding (3hrs~) I tried to turn it on to move to the garage for the night and it wouldn't start. All lights came on, but no spark or crank. Disconnected battery for 10 min, tried again, nothing. After searching around it seems that for the 1996 XJ the fuse for the rear CAT O2 sensor is also connected to the ignition system. It isn't getting power and there is no spark.

Now, I can't for the life of me find the diagrams that label each fuse for my jeep. Furthermore, when I look in the fuse box under the hood (passenger side) there is a diagram that shows what fuses go where, but my Jeep is already missing a few of these (the socket for ABS was empty, among others) and some are in the wrong spot. Did I not do my due diligence when I bought this thing? I've been driving it for 8 months with only minor problems, it has a clean carfax.

I ordered an OEM O2 sensor and I want to replace all the fuse that need replacing. If anyone can help me out that would be great. I can post pictures as well.


This is what I found in another thread:

"(PCM is grounding the asd relay to power injectors and ignition)

I know that's confusing, anyway I'd be checking fuses, and the wires to that rear 02 sensor as well. Those grounding might blow an important fuse.

I found something. There's 4 mini fuses in your PDC under the hood. Check the 15 amp one nearest the edge, nearest the relays. An 02 heater wire grounding can blow that and cause the asd to fail to provide power..."