Okay, this may or may not be a common problem but if your Cherokee starter cranks with the key off or even with the key out, this may be your thread.

First off the issue with mine. I would start the truck and it would fire up, but the starter would continue to crank intermittently with the engine running. To shut it off I pulled the starter relay, then plugged it back in, or start the truck and put it in gear which pulled ground to the relay through the NSS. So I unplugged my aftermarket remote start. It did it a couple more times and stopped for a while. Thought I solved it. Then, last Saturday, when I was no where near my Jeep, it cranked and cranked till the battery died and fried my starter (which smells terrible). So onto the cause. Water leak - from the antennae grommet where it passes through the fender into the body behind the passenger kick panel FUSE BLOCK.

This was causing a short to power on the yellow/red wire to the starter relay in the under hood fuse block. I had anywhere from .78 volts to 12.2 or B+ voltage. Bought a used fuse block, cleaned all the connectors, now I have 0 volts at the yellow/red wire to the starter relay, as I should.

So TL; DR If you have weird electrical gremlins, open up your kick panel fuse block before you fry something else.

 

Man! This sounds like exactly what I’m experiencing. Thank you very much for posting this. I’m going to pull that fuse block and see what it looks like.