2005 Trailblazer Rear Door Will Not Lock

I have a 2005 chevy trailblazer where the liftgate wont lock by either the keyless remote or the lock switch on the door panel.
2005 trailblazer rear door will not lock. 02 09 2003 chevrolet trailblazer rear passenger door lock actuator latch oem fits. There is no indication that the tail gate window or dor is ajar checked all fuses. I have checked all the fuses i can find and none have solved the problem. The contact owns a 2005 chevrolet trailblazer.
I had the panel on the inside off and the latch assembly out. 2005 chevy trailblazer ls v6. The remote keyless entry does not work interior lights do not shut off radio does not stay on after car is turned off rear windshield wiper does not work. The vehicle was taken to an independent mechanic.
When the gate is in the open position a clicking noise can be heard every few seconds. Equip cars trucks suvs with 2005 chevrolet trailblazer door lock actuator from autozone. 2005 chevrolet trailblazer ext 4 5 out of 5 stars 3 3 product ratings 02 09 2003 chevrolet trailblazer rear passenger door lock actuator latch oem. While driving various speeds the front driver side power door lock and window failed to activate.
Back door lock actuator windshield wiper key fobs all went dead at the same time. We have the best products at the right price. Is there a common point between all of these items.