Andrew, the locks don't work from the drivers door or don't work from either door? It's usually the master control on the drivers door that goes bad and on a lot of them the switch on the passenger's door is wired through the drivers door switch same as with the master window control. I think you will find the switch on the drivers door bad.

If your relay clicks that's a good thing however you still need to double check it you see 12 v is going in on the small blades powering the coil making it open connect allowing higher amperage 12 v to power the motors they need a lot of juice .Unplug the relay you will need jumper wires and a cheap muilty meter attach the small terminals to the battery it will open witch will make the wider terminals connect and send power to the drivers door master control. I f you have power their its most likely a bad connection water snow salt you just have to take it apart they wiggle wires at connectors before you rip to much apart