CarTalk.com Best of Deals Car Reviews Repair Shops Cars A-Z Radio Show

Jeep Cherokee Shuts down after 3 mins. Thinks it's being stolen. Bad Cluster?

Friend broke down.
Car would start, but would die.
Mechanic told him the cluster is bad, and the car thinks it’s stolen.
He said it’s not the ECU
He needs to wait WEEKS for the parts (unless he can get it from the junkyard)

Does this make sense?

There are some after market alarm systems out there that let the car be driven for a minute or two.
The thought being that a thief will then be wide in the open, exposed, and will not take the time to get the car started while it is blocking traffic.

Can’t he just disable the alarm system until then? Usually it just switches the pump or ignition off.

It almost makes sense, the part that does not is why does it take 2 to 3 minutes before it thinks it is stolen? I like @RemcowW advice but like a second opinion also. Were there any factors leading up to this problem?

Yes, it runs for a minute then dies.
The mechanic disabled the alarm or whatever, and the car is home.
But, it still needs to be fixed. Does it make sense that he’s suggesting a new CLUSTER?
Is that what manages this theft logic? And not the ECU?

OEM systems will turn off the fuel after 2 seconds (VTSS and SKIM).
A Cherokee (XJ) can be driven without the instrument cluster, it won’t affect the immobilizer.
Once the PCM recognizes VTSS or SKIM they cannot be disabled or removed from the vehicle, the PCM must see a ready signal from the companion module.

I think the vehicle has an add-on system, I don’t understand how the instrument cluster is involved but I am also guessing this is a 1995-2001 Cherokee.

I agree - it is hard to believe that the factory would control the alarm function through the cluster unless it was some sort of afterthought on their part when they designed the thing.
That’s got to be some sort of aftermarket feature.

It almost makes sense, the part that does not is why does it take 2 to 3 minutes before it thinks it is stolen?

If you have a thief hack into your car, you want him to think he’s successful in doing so while he’s in your driveway or garage.
Let’s face it: if they want your car, they will get it. In your garage or driveway they are not out in the open so they can potentially take their time. Make him believe the car doesn’t have a disabling mechanism. Cutting the horn out is easy so they’ll do that first.
If you make him think he’s successful in being able to start the car, just long enough so he’s out of your drive way and on the middle of the road, the he will be wide in the open with people noticing him, standing there like a dummy on the middle of the road. He’s exposed so quickly has to make a choice to either figure out why it stalled or leave the car.
Chances are he’ll leave it.

I installed an after market alarm that had that option on one of my previous cars. It never got stolen so never got to try it but the mechanism made sense.

Yea, this is a 2001 Cherokee. The cluster is dead. ALL the dummy lights are on, as well.

The cluster is dead all the time, then, even now with the truck running again?

Yes

You need to have the codes checked. Sentry Key Immobilizer Module “SKIM” could be bad, codes P1685 or P1686. This also feeds the Body Control Module “BCM”. The BCM could be bad and causing your instrument cluster not to work. I doubt the cluster is bad.