1996 Jeep Grand Cherokee with 75K miles on it. 4.0L I6 with 4WD and Automatic Trans.

I start the car and it runs fine in "park" As soon as I go into reverse the whole ignition circuit is cut (odometer and clock on radio go out as well as cutting the motor completely off). Now my question is:
1) Has anyone ever had anything like this happening to them and fixed it?
2) Is it the ignition switch or the PRND2L Switch in the transmission and if it were the second why would it cut whole ignition. I don't have service manual for diagrams so that is why I ask.

Just to let you know how this came about. Last week I went to start the GC last week and there was NO response like it was completely dead. Dome lights were fine. I moved the Shifter and could get it to start with my foot on accelerator. I went thru grounds and tested the Ignition switch and relays and fuses. I also cleaned the TB and now it runs fine but has the reverse ignition cut thing.

Any suggestions would be great.

Thanks
Tom

Sounds like a bad safety neutral switch or at the least a gummed up one.

Dave

I could be wrong but on my 96 GC it looks like it is actually in the transmission. Is this right? I had a squealing sound which I thought was the serpentine belt so I changed it. The squealing still went on and sounded like it was coming from the tranny. The jeep ran ok though so I didn't make much of it.

Thanks
Tom

not likely a neutral safety switch, if it were the starter wouldn't even turn over. don't got a clue in what else it could be sorry

torque converter problem guy!

I think that it is somthing to do with NSS possibly. Now my car will not get any power when I turn the ignition switch. I have tested the ignition switch (a couple times) and it was good. What would keep power from going to all the stuff pretty much related to the ignition switch besides the switch. Is there a master relay or would a bad NSS keep the radio and all ACC electrical items from working as well as ECU,starter,etc? I am very baffled on this one and I can normally fix anything with cars.

This is an actual story. Drove for a year with tensioner pulley bearing BROKEN and half missing. Motor was strong enough to shine the pulley(belt slipping). mileage was down. ran rough, etc. clue was the squealing every once in a while.
remove belt, by hand turn(spin) a/c compresser, alternator, tensioner pulley, etc see if anything grabs

I understand that but now I can't start the car. I get no power to the radio,a/c,dash lights, or starter. Might be more stuff but anyway. I am thinking it is a wire some where or a body control module, power control module, junction block oor something like that. Man this is real bad. What could go bad and cause a current draw on the rest of the system? The interior lights, head lights, etc work fine. I will be taking it to the dealer on monday or tuesday. I have no other choice. They will probably rape me bad. I just feel if I can't find it then they will have no clue either. Hopefully I am wrong or I get a really good mechanic on it.

If you have a POWER control box pass.side there are relays inside one is for start system turn cover lid over relays to see which is which relay Dale

I would back up and start over. Get a hot battery. If current draw is as bad as you say, have someone crank,turn acc on, etc. and feel pos batt cable/ It should burn your hand from your description if draw is that bad.
if no draw with ign switch in on(not started), I would lean toward starter
I draws with ign on(not started), disconnect alt,TCM(not ECM), etc. looking for components that could draw a lot of current and not blow a fuse.
If cable is NOT hot to touch, you have an open, not a short. Again, start with starter, like prev post said, ckt breakers, Then fuses.
Please post what resolution ends up being for the rest of us lost souls.

also, forgot to add. you have 5 grounds on Jeep. Most likely is one that connects to neg batt terminal. If you have replacement batt term end, it frequently pulls out

I am dealing with the junction box and PDC to find out what is wrong. Just for shits I changed the NSS and ignition switch (no luck) I did however come up with circuit F99 with ignition switch on feeds only 1-2 volts. That goes to every thing (ASD RelaY, Fuel Pump Relay,BCM,PCM). If I unhook the PCM (ECU) and BCM (body control module) it get power with no draw. I am thinking if it were to kill both the BCM and PCM then I have found a very expensive fix. BUT if not then I have spent A TON! I cannot believe this is such a pain in the ass. I was wondering if lightning could have done this.

I also have a 96 JGC and I'm having the same problems. I have been banging my head off the wall with this car. I had to find a message board to get help. My wife drives the Jeep most of the time and she said that if she was sittin too long that the car would slip out of gear and into neutral and she would have to put it into park and then all the way down into 1st for it to get back into gear. I guess that was going on once in a while. Then on friday morning she went to start it and there was nothing. I tried to jump it ect.... No avail. I have interior lights and head lights and the light under the hood works. The battery was tested and they said it was good. I checked almost everything for power. I am convinced I have a short or a broken wire somewhere from the fuse box under the hood to where the wires come through the fire wall. Someone here mentioned 5 grounds... Where are they all located? Also is there a way to check the sensors? I looked at them and saw that three of them have the same serial numbers on them so I switched them around just to see if one was bad. I disconected the battery by unhooking the negative terminal to reset the computer. Does that reset the computer? I was told it does and I'm pretty sure that would be fine or do I have to unhook them both positive and negative to reset ? Anyway, that also did not work or change anything. Could you provide any information about this to help me?

ground 1 is on back of radio
ground 2 is from neg post of batt to fender. most likely one to break
ground 3 is pass side rear next to liftgate(@ 12" up from floor)
ground 4 is hood to firewall right of center(pass side)
ground 5 is behind ECM computer.
There is also an "ignition off draw" fuse in PDC. not sure which. Can't believe it would cause prob, but...........
The puters themselves are very tough and designed for high temp. Rarely go bad. Most times it's something else.
Check where harness goes throug firewall for short. You are definitely looking at a short, but that much current would melt/fuse wires. Gotta be a component that can pull amos and not melt Ie. starter,alt,ac,etc.
I assume you've changed batteries. If batt freezes while discharged, plates will deform/warp and short each other out

if I jumper fuse 18 in the PDC direcly from battery then
i can get the car to start by jumping the start solenoid. The check engine light is on and ABS light. I don't believe it is the ECU now. It could be the BCM or the wire that comes from the ignition. It might be the junction box not letting enough current thru. :banghead: :banghead:

ok I took the battery out and took the fuse box under the hood apart. I am starting to trace wires. Is there anyway to test the sensors?

Update... Went over all the wires I could... Found no breaks.. Going to change the Ignition switch and the nuetral saftey switch just to be sure. After that I dont know what to do anymore.

changed the nss and the ignition switch. no luck. I'm starting to think its in the alternator or starter. I got power to all fuses and everything. It still will not start :(

Turbotom, IF you jumped fuse from ABS and it works, look in PDC for ABS "circuit breaker" not the fuse. Breaker may be stuck. pull it out, remove cover, see if contact(like the old ign points) is closed. This may be the prob.
If you still suspect BCM, check the number on it. I have a 56026993 off 93 that should be the same.
First check the cable to it and make sure it hasn't wiggled off.
Let us know what you find.
Tom Denkler

I had the Jeep towed to a guy who specializes in electrical work on cars. He also rebuilds starters and alternators. He said he will have it fixed tomorrow afternoon. I will let yinz know what it was. I bet its some damn wire I missed. I just got tired of messing with it.

I am going to run a wire from the battery to the feed into the junction box located pass. side lower kick panel. I believe this may be part of the problem. I have tested after junction box now I will test with junction box. I feel that it may be in that. Hard to say. I am running out of time to work on it now that holidays are over.

I would love to see if this guy can fix it in a day. Please let me know as soon as you here anything. I will bow down to this guy if he fixes it in a day!!

Thanks for all the help everyone has been giving. I would have shot it by now or had it crushed.........maybe fire........hhmmmm

Tom

I tried that. I jumped a line straight from the battery to the fuse box in the car on the passenger side inside kick panel. It got all the dash and radio and stuff working but did not get it started. It was back feeding and drained the battery. Dude trust me I tried everything. I will let you know soon. He said to call at 6:00 and I will also bow down to him if he has it fixed.

Hey Just checking in to see if you got any word on the Jeep. I was thinking that it could be the battery feed. I will check into that some more but it is pretty cold here now. I was also hoping that you may have heard something that could get me going again. Hope it's not too bad.

Tom

ok bro he just called. Two days he had it. He charged me $200.00 bucks... Not too bad, but more than I wanted to spend :) Anyway he said it was.... There is a bracket that holds up the cooling line. That bracket is screwed on when they build the jeep. It has pointed screws... The bracket must be screwed onto a box with wires it it. I will have him show me.... Anyway the screws puntured the wires. Over the years the exposed wires coroded and the wires finally broke. I'm going to pick it up now. He said he saved me the bracket and the wires. I can give you the guys number if you want to call him. I dont know where you live but I live in Pittsburgh P.A. and he is a good dude. Two days for $200.00 tracing wires isnt bad in my opinion. Hope that helps. I will have more info after I pick it up.

Hell Yeah thats great. I don't live near Pitt. but would love to have his number to see if he will help walk me thru it. Let me know when you find out if it is in the engine compartment or behind dash, etc. This problem may start popping up more and more. $200 is not bad in my opinion I would take it to him in a heartbeat if I lived closer.

Thanks
Tom

It's in the front of the jeep. He had to take the grill off to find it. Its on the left side of the radiator near the bottom. I think is the lower left screw that hold on the radiator. It puntured the wires on the big harness of wires that come through there. Good luck. His number is 412-824-7405 and the name of the place is Britner Automotive Electrical service.

did you get your problem fixed? My jeep is running very well now.

T Tom if you haven"t found your trouble & need a diagram for power control box. Email me at
jeepman600@aol.com FUSE #18 is a 25amp.natural color, controls Auto- Shutdown