Ok, finally got my MCS! Only took 4 weeks for the seller to finally get a duplicate title, crazy story, but I digress. Very exciting, love this car! This is a 2005 Dark Silver MCS.

When I bought the car the owner said the remote lock/unlock didn't work and was sure the battery was dead. After researching here I now know that the battery in my 3 button remote is actually charged when in the ignition, however, the cell can still go bad. But despite that info, the first day I noticed that it would work but a bit sporadically.

Not wanting to spend $160 on a new key from the dealership just yet. Figured I'd try initializing the key again and that fixed the unlock and tailgate buttons, but unlock still doesn't work. So here's the breakdown

Toggle Switch - Lock = Works
Toggle Switch - Unlock = Works

Key in Driver Door - Lock = Works
Key in Driver Door - Unlock = Works

Remote - Unlock = Works
Remote - Tailgate = Works
Remote - Lock = Doesn't Work

Anyone have any ideas? My only thought is the lock button inside the remote is bad, which means new key.

 

Really, no one has any ideas?

Just an after thought, to re-initialize the key you have to hold unlock and press lock three times on the remote, which I've done multiple times now and works, but lock button doesn't lock the car.

I did run by the local auto store and they have a remote tester that scans for RF frequency transmissions and all three buttons show as working.

Just weird!

 

I have just the opposite, the remote key fob will not unlock the drivers door, but it will unlock the passenger door when pressed twice. Hatch will unlock with its button. All three doors will lock with the lock button.

I have to use the key to unlock drivers door.

When driving the auto lock feature will not lock the drivers door anymore.

There are several posts concerning door lock issues. You can search for them.

You might also try reinitializing your key fob.

I myself am considering ordering a lock solenoid. Still researching it.