I discovered that when I lock the car all the locks work from the fab and the switch on the drivers door but the rear drivers door. It won't lock or unlock. I suspect the actuator is bad. Does anyone have any suggestions or tests to perform to isolate problem?

 

I have a 2000 LHS that is behaving much like yours. If I lock the doors with the fob, all doors lock, but if I try to unlock with the fob or the main switch, you can see the locks on the other three doors trying or starting to pop up, but not enough to unlock the doors. The locks can all be worked manually however. Noisy sounding as well. I've read on here somewhere that it's either the actuator or a drive piece associated with the actuator that fails on high mileage/well used vehicles. Mine has 249000 miles. I haven't attempted to repair the locks yet (been busy putting another engine in it) but when I do I'll let ya know what I find.

 

my locks do the same thing on my 01 concorde. except on mine the rear passenger door occasionally desides to stop working as well. i have looked into door locks for my car they are rather expensive and rather difficult to install.

 

I had a 99 concorde before I bought my 300m and one of the door locks were noisy. I went to the local u pull it wrecking yard and bought a lock actuator for $20 and installed it and the nouse went away. I am suspecting the actuator on the 300m is bad as well. By the way what engine are you putting in your LHS?

 

sorry so late in getting back to ya. I bought a used 3.5 L HO Vin G from a 99 LHS with 91000 on it. I was worried about buying a used engine, not much in the way of warranties and would hate to do all that work and find someone lied and the engine is crap, but she runs sweet, smooth idle, plenty of power. I plan on putting 100000 on her, no question.