Just bought a used 2006 Cobalt LS and looks like I have run into a common problem on this vehicle. The power door locks do not work on either the driver or passenger door. I also tried to lock and unlock from the key fob and no luck there either. The trunk release on the fob works so I know it's not the battery. I have checked the fuse in the block and it is OK. Does this look like a bad BCM and if so any ideas of the cost involved in replacing it or is there something else I should be checking first?

I dont think ls comes with auto door locks due they??? I thought LT is power everthing with center consel and LS is manual windows and doors ...but have you tryed removing the door pannel just to see if everything is connected? I dunno im just throwing something out there loll

If the car came with a remote, it should have power locks as thats the only point in having the remote, keyless entry.

Is it an original remote, since you bought it, it could easily be an after market keyless entry system that was added, as said before, LS usually does not have keyless entry, but in some cases the customer adds it on before they build the car.

You would have to take a photo of your fob and post it here so we can see if its a stock one, if it is, then we can start talking about BCM issues.

my LS and my wifes LS both had power everything (both 05's).
the fob might just be 'out of sync' with the car. this happened to my wifes where it would only lock or unlock some days, work perfect on others, and not at all most of the time.
might also be the battery.

just a heads up, it will probably be cheaper to get an aftermarket alarm vs getting a new set of OEM keyfobs. Where I am, a new set of fobs is the same price as a remote starter/alarm (installed)....kinda sad.

In addition to potential problem areas mentioned, another possibility might be the door actuators. However, please don't consider this an official GM diagnosis as we haven't had the chance to look at the vehicle in person yet.

If you make a trip to your dealership to get this looked into, please let me know as I would like to be available to assist in whatever way I can.

Sarah
GM Customer Service

He says they don't work from the door switches either.
But you can get all the parts to fix an FOB on ebay for less than 20$ for a set. check the FOB thread....

https://www.yourcobalt.com/forums/ins...-keyfob-2.html

Ah, i missed that part...got excited thinking 'been there, done that' lol

Hopefully just a bad connection or something, replacing the BCM sucks.

Thanks for all the quick replies. Just a few things to throw back at you. The car does have power windows and locks. I talked to the original owner today that I bought the car from and he told me that it is the original fob for the vehicle. It was his daughters car and he told me that the problem with the locks not working was intermittent. He said that when the door switches work so does the fob. He said this was an ongoing problem for a few years and more often then not the power locks didn't work. I figure since the fob pops the trunk lock every time it isn't the battery in the fob and since neither the driver or passenger door switches work there must be a bigger issue. Lurking around for solutions on the internet lead me to believe that it was the BCM since other owners have had the same problem. I bought this vehicle for my daughter and other than the lock issue this seems to be a terrific car. The last thing that I want to do is to take this into the stealership unless I have no other options.

Could be simple as a loose harness somewhere. Its not likely that all the actuators would go out at once. I would check all the BCM connectors, inside the interior fuse box (passenger left foot area), check the fuse for the door locks also, its in the same area, there should be a printed label on the fuse box cover panel. If this fails, you can check the actuators by removing the door panels, then check them out. You can apply voltage to the actuators to test them, if they work, you have some wire tracing to do or buy an alarm system and hook it up to the existing actuators, you may need to wire it directly to the actuators though if you have any opens/shorts.

I had a similar issue with mine. When it first started, it was just as you described, but it progressed. The fob stopped working on EVERYTHING (alarm and trunk included), so I just chalked that up to the connections on the fob being crappy. Never replaced it, just manually locked my doors (literally pushed the sticks down one by one), and manually unlocked them with the key. Then one day, my door locks started locking and unlocking as I drove down the road. My hubby replaced the drivers side lock switch ($20 or less thru GM), and no problems since. (Granted she's been parked for 2 months ish now, but still, I drove her for about a year after he replaced it, and she was always fine.) If you start getting "possessed" door locks, I can about guarantee that it's just that switch. The hubs did mine along with 2 others around the same time, and none of us have had problems since (the other 2 are friends of mine who still drive their balts). Honestly, if you can figure out how to change that switch, I'd throw the $20 into the car and see if it fixes it. I don't have a clue for sure, but I wouldn't be surprised if the messed up switch may have led to the messed up fob in my case....