My power door locks work , but when you push button to lock there is a loud buzzing noise. only lasts as long as you push the lock button. Any ideas?

 

Take off your door panels and disconnect the actuators from the lock linkage. See if the actuators move when they are not trying to move all of that dirty/rusty linkage. If they do, just spray all of of moving parts of the linkage with white lithium and cycle it by hand until is starts to move more freely. That worked for my drivers door...but my passenger side needed a new actuator. They are pretty easy to install unlike window motors or regulators. Just a couple rivits to drill out and replace with threaded hardware.