My 99 shelby d's drivers door will not lock/unlock from the outside now when you insert the key. The inside power door locks do work for all doors and the drvrs door key will turn the tumbler left and right but will not lock/unlock the door. This just started on Saturday and don't know why. Before I remove the drvrs door panel does anyone have suggestions on the possible problem. I believe its a mechanical issue.

 

it is a mechanical problem, im not sure how the key lock (tumblers) link to the lock, so you will have to open the door up and take a look but open it up and take pictures if you happen to get stuck