dfranks

My rear driverside door lock will not lock. I performed a diagnostic test of the instrument cluster posted from this site.

The codes are

C 44.7
S 12.5
. 28.3

I opened up the wiring harness that attaches to the door itself and put a meter on the Truck side of all of the pin connectors, while i locked and unlocked the doors with my key FOB and sure enough I am receiving power at the harness exatly when I turn on and off the locks.

At a loss for words hopefully one of you will chime in a shed some light on this. My next order of business is to clear the DTC's with my smarty and see what happens

BlastMaster

Those don't appear to be codes, they look like other info you can retrive from the odometer window (running hours, etc)

From what I know, all the codes are 4 digits.
What you need to do is the "key trick", not the instrument test.

Cycle the key (quickly) three times, leaving it in the "on" position the last time (not start, on).

That should pull the codes, if any.

bumpytruck

I don't know about those codes.But my guess is the lock actuator inside the door.