I have a 2003 Expedition. My extended warranty will be running out the end of June, so need this figured out! My dealership can't get this right.

Problem: Door locks are not working. Started with the rear passenger door. Took it to dealership and the replaced the actuator. When I picked it up, still didn't work. It would work sometimes and then it would not. Same problem with door button or using key remote. Problem then progressed to other door locks. They then replaced whatever it was that caused a new code to be used in the key-less entry. Problem solved for 3 weeks, and now the rear passenger door lock is acting up!

Also at the same time the engine started to run real rough. When at idle it would almost stall out! They replaced the O2 sensor and the throttle control air valve. This was done at the same time as above was replaced. Now that the rear door lock is acting up again, the engine is starting to idle funny again. Can this be caused by the same problem. Computer chip? It is worse when the A/C runs. Also, there is a noticeable whining noise when the compressor of the A/C runs. This is new. Can it all be the same issue or are they all just perfect timing? I know this is a rambling post, but I hope someone can help, my wife is looking to me for the answers!

Please ask any questions that may help to clear this up. In summary: door locks are randomly locking with no pattern noticeable. Rough idle and compressor seems to be whining very loud!

Any help greatly appreciated!!!!!!

 

If your dealer has agreed this is an intermittent issue, it should remain covered even past the warranty date.

 

Since all of the doors (except the driver's door) are controlled by the same unlock relay, the problem has to be a bad splice. They probably replaced the keyless entry unit and in doing so moved the wires around under the dash. This is likely why they all worked for a while.

Another possibility is a loose or corroded battery to body ground wire. This of course would also make the engine run poorly.

The A/C whine is probably a bearing going bad in the compressor.

 

When you lock the doors, is the horn loud or is it muffled? I was having the same lock problem and it turned out to be my battery and a bad cell. I know it sounds stupid but that fixed mine.