Ok so when i bought the truck the master door luck switch would not unlock all doors only drivers door. No big deal (I thought) just replace the 20 switch and it would be good as new.... Well new switch and still a no go. I also after the fact noticed the factory key-less entry door locks (key pad) is not working either. So now I am wondering if that has some correlation to why the door locks are not working. Anyone ever work on the key pay or know how it works and if that could be my problem??

 

Pull back the rubber boot inside the driver side door jamb and examine every wire for damage. The culprit is probably a wire that is cut in two due to constant opening and closing of the door. It happened to 3 wires on my truck. Easy fix though, use two but connectors and a 3" piece of wire (if that is the problem)

 

Long shot I think, but check your fuses just in case. After you do bourgeois's suggestion. If they both check out, pull the switch box out of the arm rest, flip it over so you can see the plugs, and shove each wire into its spot in the plug firmly. They loosen up sometimes.

 

This exactly^, I can't count how many times I repaired wires inside that boot for the very reason described. Very common. Also pull on the wires going into the bottom of the switch to see if any stretch, they had issues of breaking inside the insulation right at the connector.
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Today mine was acting up, Drivers door would not lock or unlock, then it worked , but then would not lock the rear doors. now seems to work. Loose wire maybe??? (with outside door handle lock, remote key and inside pad on drivers door all had same issue)

 

I'm having the same issues 2 doors lock and the other 2 dont. Checked all fuses inside the truck and we're good...but also my heated seats aren't working either so I'm still searching for the problem