Need Help, Strange Problem

After about 20 minutes of driving my 2001 Impala LS the message center light "sevice vehicle soon" light comes on. A minute or two later, it blinks a message "door ajar" and at the same time there are three chimes and the door actuators try to lock the doors, that are already closed and locked. The "sevice vehicle soon" light then comes back on and the "door ajar", chimes and actuators cycle again. This keeps happening until you shut the car off for a few minutes. When you restart it, everything is normal for another 20 minutes or so and it starts all over again. Everything else in the car functions normally. I did notice that when you are stopped at a traffic light. The "sevice vehicle soon" light stays on the locks don't cycle. It seems to have something to do with the system that locks the doors when the car is in motion. Any suggestions as to what the problem might be??? I also checked and there are no codes.

how many miles? still under warrenty?

sounds like the radio or BCM to me.

It has 65,000 miles and I have an extended warranty until 75,000 miles,
so I quess it will be covered if they can find the problem. It seems as though something heats up after 20 minutes and then starts going crazy. I drove it to work today, which takes about 18 minutes and I had no problems.

well extended warrentys usually dont cover electronics and such, unless you purchaced a bumper to bumper extended warrenty, but if its just a powertrain, they wont fix it.

the BCM's are very touchy in the impalas, and are common to fry themselves, so that might be something to look into.

I only said the radio cuz the chimes and such are controlled by that, but I think the BCm still controls the radio, and it also controls all the other stuff going wrong.

id say replace the BCM and it should fix it.

but the BCM is a ONCE only programmed thing, so you have to buy a new one, and get it programmed to the car and the vin and whatnot. so your pretty much stuck going to the dealership for that one.

but then again, I dont know everything, so I would say still look into it.

I left it at the dealer this afternoon. They are thinking it's the BCM also. My extended warranty is bumper to bumper with a $50.00 deductable. So whatever the problem is, it will only cost me $50.00. I'll know by tomorrow what the problem is. I'll keep you posted as to what is wrong. I'm glad I purchased the extended warranty, with all the Impala problems, it will pay for itself. It already paid for two intermediate shafts, a rear wheel speed sensor, tie rod end, and fuel level sensor. I'm wondering what will be next.

well im sorry to hear about your problems, I havent had any except the intake leak, so either im lucky/it just hasnt happened yet/ or since it ws used, the first owner had to deal with it.

but im also glad to hear that I have a good chance of being right, im usually just close, not often quite on. so yes, please keep "us"/me updated to see what the problem ended up being.

I got my Impala back this afternoon. The dealer had to replace the BCM.
The car seems to be working fine now. I'm glad I purchased the extended warranty, otherwise I'd go broke paying for all these little problems. I really like my Impala, even with it's minor problems. It gets great gas mileage, has plenty of power, handles well, it's comfortable on long trips, and has a big trunk for all the wifes luggage when we travel. I don't know what I will buy when it's time to replace it. I'm not too fond of the new Impala's look. Maybe it will grow on me. Thanks for the help. This forum has allot of good info.