Hello everyone, i have a 06 mustang gt and have been having the strangest probelms and havnt found an answer anywhere. I dont want to take it to a dealer where they charge a sh*t load and take alot of time, when i can do it myself, i just need the diagnosis.

So here is the problem, the interior door lock switches dont work. The driver side doesnt work with lock or unlock. The passenger side only unlocks and it has a slight delay. The key fob doesnt lock and only unlocks.

I know its not the motors as i did the steps used to program a new key which locks then unlocks the doors and it works fine. I dont think its the switches because they are still illuminated as well. I checked a couple fuses, none of which were bad. I dont know where to look and have never heard of this happening to anyone else so hopefully you guys can help me out

 

Just because the switches are lighted does not mean the switch is good. However since using the key fob and hitting the switch produce the same result, logic dictates switches are good and so are the fobs. Reprogramming the key makes everything work properly, which should eliminate the door lock motors. That leaves one item they all have in common, the body control module. However that gets used when reprogramming the key. This is probably not something that can be diagnosed via keyboard, unless someone else has experienced the same thing. A shop visit may be in your future. Especially if the BCM is defective. Those usually need to be programmed to the car when installed.

 

I am currently having this same exactly issue, have you solved it for found how to fix it? I’ve been having to lock my car manually from the inside just to lock it and my key fob works unlocking it, and only passanger door unlock works , but not the lock button, and nothing on the driver side .

 

Check the SJB behind the passenger side kick panel for water contamination 'cause that's a common source of electrical gremlins.
The root cause is blocked cowl drains allowing water to overflow from the cowl into the passenger side footwell via the cabin air filter.