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03 rear doors not locking


Full Member
Apr 10, 2007
Nashville, TN
I've got a naked '03 that I just bought last week. The rear door locks worked fine, but now BOTH of them don't lock with the power door lock on the driver door or with the remote. It's kinda weird that they both went out at the same time, so I thought it might be a fuse, relay, or a programing problem. I don't think I have the DIC programming thing (at the least the instructions in the owner's manual didn't seem to do anything).
Any ideas?
I tried with and w/o the child locks. Didn't make a difference.
The dealer didn't know what it could be, either. He thought it sounded like a programming error. Said I'll have to make an appointment for them to hook it to the computer.
Someone mentioned resetting an '02 "back to facotry settings" by pushing lock, unlock, unlock. That didn't do anything.
The owners manual gives some directions to set the door lock delay mode, but i couldn't figure that out either!  :E:

Thanks for the help. Found out it was a bad lock relay. There are two, one to lock and one to unlock for the back only. Another member suggested I switch them and at least they lock now. I can go without unlock for a few days until I get the part.
The rear door locks are controlled by the BCM, via those relays. Unlike that of the front locks which are controlled each by the door modules. All communicate via the class II bus.

Good find... Good luck!

I had the same thing happen to mine they traced to a short in the small fuse box just inside drivers door. they replaced fuse panel about a month ago and every thing is fine now. mine is a 03 also
Iv'e got an '03 that I bought new. Iv'e had all kind of electrical problems with it including the back doors not locking and then not unlocking, the check engine light coming on, the windsheild wipers not shutting off and different messages coming up on the message center. I don't want to bum U out but I'm going to arbitration tomorrow to try to get some money back for repairs that did nothing. Every time I bring it to the dealer they want to replace something but it is always a temp fix. I hear a lot of the problems may be related to the Body Control Module but I couldn't get them to replace it. Reprogram they will but not replace. Good luck. :E: