Our 98 Grand Caravan started having alarm problems in September. The anti-theft alarm goes off occasionally when the car is parked with the doors locked. It doesn't matter whether doors are locked with the key, the remote or the button on the inside of the door. We've tried every suggestion we've found on the Internet whithout success. The car is older and I realize electrical issues are common but also know they can be very difficult to diagnose. It can be really embarassing to have the alarm go off so we are often forced to leave the car unlocked, or pull a couple of fuses. Neither are good solutions. The mechanic at the dealership said he doesn't know whether a factory-installed system can be inactivated. Does anyone else know for sure? I don't want to pay for service and rent a car for a couple of days if there's no chance of success.

 

Welcome Aboard let98007! By any chance did you leave this question on Just Answer? If so, they replied - take a look at Dodge Grand Caravan ES: how do you disable the factory alarm (...You cannot simply disable the factory alarm on this vehicle unless you replace the PCM (engine computer) and BCM (Body Control Module)...more...

 

And when you replace them both, you also need to disconnect the key cylinder switches or the first time you use your key, it will reenable itself.

Check your door ajar switches, they become out of adjustment and is the usuall cause of the alarm issue. Push on the rear of the doors from the inside,if the dome lamp comes on, the switch is out of adjustment and needs to be replaced.

 

Thanks for your response Tizzy1. I'm confused by vpnavy's response. I did not post on Just Answer. Has someone hijacked your page? Vpnavy's quoted text refers to a slightly different problem involving an aftermarket device that was posted on Just Answer 26 months ago. Does the information still apply to my unmodified factory-installed anti-theft system? I have checked all doors and no lamps come on. Obviously something needs to be replaced but finding out what could cost more than the car is worth. At the moment, it is our only means of transportation. It is inconvenient to have to remove fuses in order to lock the car. Is there any solution?

 

Sorry let98007. I had a senior moment and got your request mixed up with someone elses. Sorry.

 

The response in the link is still applicable, you would need to replace the PCM and the BCM. Those are the 2 modules used in the theft system. If just one is replaced, the other tells it you have alarm and turns it on by itself. If both are replaced, you need to disconnect the key switches because seeing an input from them lets the BCM know you have an alarm and it turns it on.

 

Thank you for clarifying that. It seems such a shame because the van runs perfectly and is still one of the best looking vehicles on the road in my opinion. However, having the alarm go off all the time severely limits its usefulness and our lifestyle.

 

I still think you have a bad door ajar switch.

 

don't know if this applies to dodges, but i have an 01 maxima and the same thing started happening. turns out the dome lamp switch was in the wrong position. hope this helps.

 

Tizzy1, It turns out you were close: The dealer was finally able to get an error code and it pointed to the hood switch. They were able to bypass that switch and it seems to be working. I haven't heard a peep out of the anti-theft alarm for over 3 weeks now!

Thank you all for your help!