dodge '03 quadcab pickup doorlock problem

The electric lock on the left rear door does not work. Is there a fuse or relay I should check before going inside the door? If not how to test door lock motor?

if it's just the one door it porbly won't be a fuse problem.  take a part the door and use a multi tester to check voltage going to the motor, if it has no voltage  you shoud check the wire running in side the door maybe it got pinched/cut/disconnected doing a speaker install or something.  if the motor has voaltage then it could be the motor is bad or the motor is jammed some how, try to move the door locks manualy and check for life from te motor.   it will probly be a bad motor, you can usually use a standard after market actuator to fix the problem.life is a comedy to think, a tragedy to feel