Anti theft module replacement/swap

CHOWSKI12

MEMBER
2005 JEEP GRAND CHEROKEE
V8
4WD
AUTOMATIC
150,000 MILES

Hello,

We have the vehicle listed above that will open and start. However, when it is put into drive, it will shut off. The dealer is saying that it is an issue with the anti theft module.

They have informed us that they do not make the module that we require anymore. We are wondering if we can pull used computer modules from another Jeep? The dealer was not very clear and mentioned we may have issues with the key fob etc. I read your post outlining the body module learning from the engine module etc.

We have a 2004 Grand Cherokee from which we could pull anything off. Is it possible to replace these computer parts and get the 2005 going again? The dealer is basically telling us that the Jeep is toast.

Regards,

Luke

1 Reply

CARADIODOC

MECHANIC
33,916 POSTS

Sounds like you need a new dealer. First of all, if the engine starts and runs for more than two seconds, it is not in theft mode. The very common cause of stalling when put in gear is idle speed is too low. You can verify that by simply holding the accelerator pedal down 1/4". You often need to do that too to get the engine to start. An additional symptom is the engine will tend to stall when you approach a stop sign.

This happens when the battery was recently disconnected or run dead. The Engine Computer relearns all other data right away while you are driving, except for "minimum throttle". You need to meet a very specific set of conditions for that to be relearned. To meet those conditions, drive at highway speed with the engine warmed up, then coast for at least seven seconds without touching the pedals. Most mechanics do this for you on a test drive when they had the battery disconnected during other service work.

You might find more information in this article:

https://www.2carpros.com/articles/stall-at-idle

As for the computer modules, rebuilt units are available to the dealers from a number of sources. The anti-theft system is built in as part of the Body Computer and the Engine Computer.