I have a prolem with the driver door lock that started this morning. When I use the remote to unlock the doors the passenger door will unlock but the driver door stays locked. I have to use the key to get in. As soon as I remove the key it remains locked. If I use the lock button on the arm rest the passenger door will unlock but the driver door stays locked. The driver door will unlock if I am in the truck and pull the door handle. The door knob is always down in the locked position. If I pull the knob up it wll go back down as soon as I release it.

Can anyone give me an idea what to look for, and how to check for an electrical problem?

Thanks,

Raul

Sounds like you need a new lock actuator which is sold as a complete latch assembly.