I have a 2005 Honda Accord EX 2.4L with 180,000 miles on it. I recently bought this car as a daily driver, the only issue I have is that I have to manually lock the front and back left side doors. I am considering replacing the power lock actuator on both doors however I wanted to know if there is anything else I should check before proceeding with doing that.
Check the wires where they pass through the door jambs for broken, frayed wiring.
Before replacing the motivators you could use a test light on the connections inside the doors to see if they are receiving voltage. (That symptom could be caused by a wiring problem due to wires flexing with the doors opening and closing.)
As Doc and Chuck Tobias said check the wiring in the door look for frayed wires and use something like test light or multimeter.
