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1996 Honda Civic LX - Power locks randomly actuate

I apologize in advance if the solution to this is the same as the recent post regarding the 1986 Lincoln.

My 1996 Honda Civic LX is a peach. I love my car, even if it has 190k miles on it. I do all of the regular maintenance as prescribed by my manual.
A couple of years ago, I noticed that when I locked my car using the inside drivers side switch, the motors (or whatever electronic motion creator) still actuated, even though the door was still locked. It would do this for any length of time. Fearing a dead battery at some point, I took it to the dealership I bought it from. I have no complaints about them, btw, they have always been good to me - but they couldn’t find any problems with it. My power windows weren’t working, around the same time, so I had them repair the connectors between the doors. The windows work fine - no problems.

So, a year passes. This locking problem is intermittent, and has never locked me out of the car, but I have noticed that the “all lock” feature, activated from outside by turning the master key in the drivers side door, no longer functions. I start to notice a trend in the pattern of this lock actuation - it happens when it rains, and when it seems to be particularly humid outside.

Finally, today. A beautiful day - sunny and warm, not nearly as hot as it has been. My locks start acting up the entire time I am driving home from school on the interstate.

So, I need some help. I have had the door panels in my car off, so I feel fairly confident that I could do a repair prescribed by the community. I hope you can give me some direction to go in.

Thank you for your time.

Have you visually inspected the condition of the wire insulation? The wire that passes into the door panel near the door hinge.

Honda had issues with the master control unit located in the drivers side door for cars of this era. We had the same problem on our 97 Accord, but fortunately for us, it happened during the warranty period. The invoice to Honda for the repair was $200.

Seen it happen before,think our 97 Accord wagon would do this occasionally(hate PDLs)-Kevin ( mercifully they finally stopped working on our 2000 Focus,this car had window cranks too)

I have inspected the wiring through the door, and it seems to be good - I actually had the Honda dealer repair those about a year ago, due to an issue with the power windows and mirrors. The issue with the locks was happening at the time, but because the dealership couldn’t replicate the issue (because it wasn’t raining or very humid out, IMHO), they couldn’t fix it.

Would an issue with the master control unit cause the problem I describe? I was thinking about the actual ‘actuator’ - isn’t there some kind of position sensor (locked, unlocked) inside of it? I need to look at the schematics and see if I can come up with something. Any advice?

The master control unit is a known issue with Honda’s of this era and the dealer should know that. I had a problem with my dealer on this one because they couldn’t “replicate” the problem. The reason they couldn’t replicate it was because it was too noisy inside their shop.

On my second trip where I was told they couldn’t replicate it, I took the car to the back of their lot and parked it over night. The next morning, I dragged one of the service writers out to the car and there it was, constantly actuating the locks. Thats when she said, “Oh, thats a known problem, they should have just replaced the master control the first time”. Its funny, I got a customer service survey on this visit, as I had on all previous visits, but it was the last one I ever got from this dealer. I did not put a “happy face” on that survey.