stuck in theft mode

1998 JEEP GRAND CHEROKEE

159,000 MILES • 5.2L • V8 • 4WD • AUTOMATIC

RACHEL SMEALL

MEMBER
1 POST

Hi, my vehicle listed above is stuck in theft mode. the car will start for 4 to 5 seconds but shut off immediately after my dash board doesn't work except for my blinkers and ABS light. my roof reader stopped working. after so many attempts to start the car the theft light comes on 30 seconds to a minute after the key is turned to the place before you try and start the car. the horn isn't honking the lights aren't flashing we have tried every thing that disarms the theft but nothing is disarming it for some reason. it hasn't ran in almost 4 months. i took apart the BCM and its not fried or burnt but a code reader was hooked up and its not showing any codes besides the crank shaft sensor and we replaced that but its skipping over the BCM when its scanning so i'm not sure what's going on. i would really love my car back i love my vehicle. any help would be appreciated.

Jul 18, 2020 at 6:49 AM

KASEKENNY

✓Experienced Mechanic
18,907 POSTS

What was the crank sensor code that you had? Do you still have that code? Also, when you say your scan tool will not talk to the BCM, that may be your overall issue. Notice where it talks about how the BCM receives the unlock signal from the Passenger door module and RKE over the CCD bus where the BCM will deactivate the alarm.

What type of scan tool are you using? Has it ever worked on this vehicle to talk to the BCM?

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Jul 18, 2020 at 10:49 AM

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