Looking for some help on how/what to diagnose where the problem is with my tailgate. I'm figuring it is the actuator, but not sure where it's located. When the truck was under warranty the tailgate would not open at all. They replaced the actuator under warranty, but now the gate will not lock at all. Tried with the remote and door switch. I also recently noticed that when I leave the tailgate open I do not get the idiot light on the dash to tell me it's open now. Can someone tell me where this actuator is and how to test it or should I just go buy a new one? TY

 

Make sure you don’t have the key in your pocket, at least on some trim models with the remote access key the tailgate will recognize you have the key and will automatically unlock whenever you walk up to it.

 

Check the connectors and wiring for the tailgate. You may have to drop the spare in order to get to them.

 

Yes, check the connections underneath and use dielectric grease on them.

 

When I first go the truck I did drop the spare and hit all the connections under the truck with grease. Guess I'll check them again.

 

My experience with the tailgate actuator,,,, I looked at many youtube videos and discussions about the problems with actuators relative to the locking and unlocking of the tailgate. I never saw one that dealt with what I found the problem to be. My tailgate went into the would not unlock mode a couple of times. I took the panel off the tailgate to look at the tailgate handle mechanism. This is a 2017 250 Super Duty lower model with a lot of addons. I saw a white box type housing that had a two prong power connector. I removed this box - it has 2 mount screws. There is a spring loaded white plastic piece that slides in the top of the box that isn't part of the box. If I moved the piece that slid into the box it would activate or deactivate the tailgate release handle. So clearly the box wasn't working because there was no movement when I tried the electric lock. The plastic box had a lid that snapped on with those barb hook things on the corners. I used a small screwdriver to get those released. Inside was what I would call the actuator motor which had a plastic gear on the drive. That gear drove another gear which activated a worm drive that moved the spring loaded plastic piece with a high and low side on the worm drive. The issue I found was the two gears had somehow wedged into each other and locked up. The device wasn't working. I pushed on the plastic gears and they unlocked. The actuator then worked fine. I did test to see if I could get it to freeze in the unlocked position and best I could tell if it is unlocked and you pull the power connector it will stay unlocked. The key was the position of the worm drive. The plastic box does slide into a slot on the mounting bracket where it screws on so be careful with that. Just pay close attention to how everything fits together. Mine is still working but I expect it will stop again at some point. Could not find a replacement part.