2002 tahoe power lock problems

I have a 2002 tahoe that has been burning out drivers door lock acuators. This time it started to contiunally run the motor in the acuator and now none of the locks will work. I have checked the fuses there are 3 or 4 labled for the locks. There are 3 relays. I got a new relay and have rotated them so to eliminate each one with no luck. they do click when I plug them in, so there is power to them. I unpluged both the drivers and passangers switches. I even took the battery out of the key chain remote thinking it may be sending a steady signal. What else can I try?