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On this vehicle you have 3 relays, a driver door unlock relay, door lock relay and door unlock relay.
How the system works is the door lock switches ground the coil side of the relays,this energizes the coil side of the relay which creates a magnetic field which closes the switch side of the relay which then lets current or voltage flow to the door lock actuators.
Here is the wiring schematics for this.
Now on the first schematic see the door lock and unlock relays and pin 85 this is the ground side of the relay coil circuit. Now on the second pic see A and B this is the feed from the switches. As you can see this is a ground. Now you can disconnect the switches and ground the Pk/LG wire and see if the door unlock. If they do then you have a bad switch,if they do not then go directly to the relay and ground it there,if they unlock then you have a wiring concern.This will usually be in the harness where it goes from the door to the A pillar if you have a wiring problem.
The relay box is located on the drivers side behind the quarter trim panel,you can usually remove the cup holder in the trim panel to access them.