Jeep WJ died while commuting -- now in anti-theft/immobilizer mode? Ideas?

Troop92

Well-Known Member
Location
Layton, UT
Hey guys, any help would be greatly appreciated, and my wife would apprecaite having her car back... Vehicle is a 2002 Jeep Grand Cherokee (WJ) Overland -- 175k miles

Was driving about 60mph on Legacy this morning on the way to work, everything fine..... then the Jeep hesitated, then completely shut off. Gauges turned off, no throttle response, no power steering or brakes. Thankfully traffic was light and I was able to get to the shoulder. Turned the jeep off, let it sit a minute, then tried to start -- it will crank but won't fire. The immobilizer symbol (key with a slash through it) is illuminated. Waited/tried to start for 30+ minutes, nothing. Had a tow truck take it home.

My keyfob hasn't worked since I bought it 10k miles ago, but the key worked fine to get into the jeep. Just a few weeks ago, the key wasn't always disarming the alarm system, so I just started locking the door manually, which doesn't arm the system. Nothing out of the ordinary this morning, unlocked my jeep, drove 14 miles from home and had this happen.

Insult to injury, the alarm is activated, so every time I try to start the car or even open a door the alarm goes off for the 3 minutes until it resets itself. I can't get the key to deactivate the system.

Any ideas? Am I about to get raped by a dealer to fix my key/fob/alarm? I'm going to check all connections (battery, in the door for the key/alarm) and go from there. UGH, it was running so well.
 

sawtooth4x4

Totally Awesome
I think you have to resync the key to the computer. if i remember right there is a special sequence. put the key in the door and turn it one way a couple of times then the other way a couple of times.
 

Troop92

Well-Known Member
Location
Layton, UT
I think you have to resync the key to the computer. if i remember right there is a special sequence. put the key in the door and turn it one way a couple of times then the other way a couple of times.

I was just reading up on this... As I only have one key, I have to get it programmed at/by the dealer. Yay.
 

sawtooth4x4

Totally Awesome
Sounds like my land rover. at least a non programmed key still works in mine though. my last range rover though, if the key died, you were screwed. The new keys cost $300 to get and have programmed.
 

Troop92

Well-Known Member
Location
Layton, UT
My key fob hasn't ever worked either, not just a dead battery as believed.... Irritiating, jeep was running amazingly well pulling down 18+mpg doing 70 on the freeway.... :(


Okay, then, the question becomes how the crap do I get it OUT of that anti-theft state so I can get it to a dealer for the key re-sync?
 
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Troop92

Well-Known Member
Location
Layton, UT

Thanks for looking, man. The jeep is at home, so I can take some time (maybe a good thing the Murano hasn't sold...) but still want to know and get this handled ASAP. My symptoms are a bit different in that I have power inside, the alarm is going off (irritating), etc. It just won't start, with the Sentry light on in the dash (an encircled key with a slash through it). I'm thinking it's my key/Sentry system. I've found a few places that will do keys that aren't dealerships, but the dealers can check if the Key is talking to the system, and the system to the car, etc.

One locksmith warned that the keys usually just don't "lose programming" and that it could be the RF receivers in the ignition or something like that.... UGH.
 
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sawtooth4x4

Totally Awesome
there has to be some magic trick to disarm that crap. can't the dealer get into it with their special scanner and turn it off? I'd call and see if they can bypass it. you don't want that crap happening in the middle of no where.
 

Troop92

Well-Known Member
Location
Layton, UT
there has to be some magic trick to disarm that crap. can't the dealer get into it with their special scanner and turn it off? I'd call and see if they can bypass it. you don't want that crap happening in the middle of no where.

Not so much, though I read an obscure post about a locksmith being able to flash the ECU to rid the vehicle of it... I'll have to tow it to a dealer tonight or this evening, it seems. Or just have a key guy come to me and see if that reprogram fixes it, and if not then take it to the dealer.

I have a friend of a friend that works at Bountiful Jeep that might be able to hook me up, but I'm not sure if I want to tow it, unpowered, all the way to Bountiful...
 

Troop92

Well-Known Member
Location
Layton, UT
can you pull the wire off of the horn, so you can think straight while working on it?

Oh yeah, I'm going to be pulling the relay as soon as I get home... I was disconnecting the battery on the side of the freeway today and am about deaf because of it.
 

Troop92

Well-Known Member
Location
Layton, UT
I can help you tow it if you'd like. I don't know if I can get a trailer. I won't be home. Until tomorrow

So you're saying your super available..... ;) Thanks, man, I'll keep you posted.

I've talked with a few other WJ owners that have had very similar experiences, and they all said the following is the chain to follow:

1) reprogram your keys (I'm getting another key, so that's fine)
2) replace your PCM
3) replace your crankshaft position sensor

I'm also going to look at the door switch that disarms the alarm. Not having that blaring at me would be fantastic...
 
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Troop92

Well-Known Member
Location
Layton, UT
UPDATE

tonight it came out of Sentry/Anti-theft long enough for me to deactivate the alarm, so that's cool.

But, it died again in the same way merely pulling out of my driveway. Pulled a P0725 code, and the Sentry, CEL, and Fuel lights all illuminated. From research, looks to be either the Crankshaft Position Sensor or the PCM.
 

rustyjeep21

Member
I have no idea on WJs but this trick does work on XJs and ZJs. When the alarm is acting up use your key in the trunk to lock/unlock the vehicle.
 

Troop92

Well-Known Member
Location
Layton, UT
Change the CPS, from what I've been reading that should fix it.

Going to pick one up on the way home, guess I'll start with the cheap stuff...

I have no idea on WJs but this trick does work on XJs and ZJs. When the alarm is acting up use your key in the trunk to lock/unlock the vehicle.

Yeah, WJs only have a key on the driver door. Jeep in their infinite wisdom doesn't want you to easily access anything.
 
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