I have a 2010 fit and recently the door locks have started to randomly engage/disengage while driving around. It seems to be totally unrelated to speed or acceleration. It also seems completely random as to whether it does a 'lock' or 'unlock'. I'm guessing it maybe some faulty electrical connection somewhere and am kind of dreading the troubleshooting process.

Has anyone else dealt with this? Any tips on the most likely/easiest items to check first? Or tricks to making the debugging easier?

 

I would start shaking things while the car is parked to see if I could get it lock/unlock to help isolate the issue to a certain spot.

Door panels
Under Dash wiring

 

This was a great suggestion! Unfortunately I can't reproduce it no matter how hard I bang/bump/jostle any of the inside door panels anywhere around them. I am tempted to just live with it.

Haven't tried jostling the under dash wiring yet though- will give that a shot tomorrow..

 

There is an "Actuator" that functions to automatically lock the doors once the vehicle reaches a speed of 10 mph. I had mine replaced twice at the dealership and it is again malfunctioning and acting the same as yours.

I've not yet dug into it but the following video definitely has my attention: Worth a try for $5.00.

 

Replace the driver side door actuator for my daughter Fit when it was locking and unlocking. Found one at the local recycle yard for $20.00 and about 45 minutes worth of my time to remove the door panel, use a hammer and impact to remove the phillip screws at the recycle yard. I bought the screw buster at the Eastwood store along with my air hammer to remove the phillips screws when I went to remove the actuator on the daughter Fit.
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