My front passenger door lock doesn't work sometimes, lock or unlock. After driving for awhile it will start working normally. This happens almost everyday. It will not work then work... Only the front passenger side.
I already replaced the actuator with a known working one. I don't think that's the issue.
The lock switch is also not the issue; tried both driver and passenger sides. Same with my key remote.

Is there another component I can check? What other parts is in the door lock system? Is there a control unit?

Thanks