HP2

'96 Grand Cherokee Limited. Picked this Jeep up dirt cheap. Got it from a local farmer. His daughter was driving it down the road from their house when a driver ran a stop sign and tagged the driver's side front fender. They claim they drove it home the quarter mile up the road after that, then parked it out by the barn for a year before I picked it up. It had no battery in it when I got it and had obvious mice nests in the engine bay. I cleaned them out and didn't see any obvious wire damage.

Now I got it at my place. The body repairs will all be pretty straight forward so no problem there. I took the battery out of my '98 to attempt starting. As soon as the battery was hooked up, the lights started flashing. Going to the cab, I notice some of the dash lights are flashing in sync with the outside lights and the security light is on as well. Installed the key, turn to run listening for the fuel pump, no dice. Various dash lights do come on with the key being turned. Engine will turn over.

So, with the Chrysler Collision Detection System, Automatic Shutdown Relay, obvious Security system malfunction, and potential for rodent damage, I'm looking for suggestions on what components/systems/harnesses to start diagnosis and repairs with to get this thing to stop flashing its lights and fire the engine back up.

jon-d

looks like you have some troubleshooting work ahead of you. I would start with disabling the alarm. do a search, but there is a wire (purple/white? - I cant remember) located on the drivers kick panel that needs to be grounded. that should end the alarm problems. BTW, the first couple nights I had mine the alarm would go off and wake up the neighbors. the wife was embarrassed and mad at me so it was a priority to resolve.


after that the only thing you can do is start following the wire looms and see if there are any obvious repairs to make. I would start in the engine bay at the fuse panel and trace out from there. also check fuses to see if something burned indicating a short (chewed wire) and so forth. let us know what you find.

dave1123

Be sure to check the wiring on the bottom of the relay/fuse panel under the hood. It's a nice place to build a nest. Most of the reason for chewed wiring is the salt content from road grime. Up in my area, porcupines love brake hoses!

HP2

I've already started verifying continuity with the fuses in the PCM. Then I'll move on to relays and then hit the inside fuse block.

So far, the nests I've cleared out do not show any obvious critter damage around them. But, I'll need to remove some components to access enough of the harness to verify.

HP2

Still working my way through fuses and relays while fixing other items along the way.

I removed the largest two mouse nests under the hood; one by the brake booster, the other under the ABS system brackets. Looking closely at the harnesses in these areas, they have no damage, so that is a good thing. However, human caused damage by the installation of various sound systems may be another matter.

For grins I tried turning it over. It actually fired on a few cylinders initially. Enough to shake around a bit and then stop. So, no consistent fire yet and I could not duplicate this effort any time after that during the day.

So, rather than just disable the alarm, are there any methods for resetting it at all other than the flipping the key back and forth in a door lock? Since I had rear hatch problems and I've read about issues with the security system originating from there, is there a sensor back there I should be checking?

HP2

To Follow up; Locking and unlocking the doors reset the alarm system and allowed to turn over. It still wouldn't start but further investigation revealed a cracked distributor cap with the center post totally burned away. New cap and coil wire and it fires up finally.

I did have some issues with the rear hatch lock, so I had some adjustments there to perform. Over time, I suppose the rod slipped just enough in its clip to not fully engage/disengage. Had a similar issue with the rear doors not always opening either that required a similar adjustment to the button throw and now that they are adjusted they open first time ever time.

Ahh, working on old junk...

97grand4.0

Yep the two front doors and the hatch all have little plastic switches on the back of the key cylinders that go bad ...and the hatch has a system of detector switches to sense the lock, glass, and hatch. I have bypassed all these to solve my issues. Not that it matters because the back hatch doesn't really open anyhow, and I like being able to just push the button and open the glass even with the vehicle locked