I noticed while under the passenger side of the truck I had this plug that wasn't plugged into anything and nothing close to plug into and to cover. it is directly under the passenger compartment running parallel with the passenger side rocker. Any ideas?

 

I believe it's for the electronic air suspension on vehicles equipped with the option.

 

There is a sensor there one of my trucks i think it is the one with ACE.

 

It was not for the SLS system, all that wiring was under the drivers seat on the frame. As for the ACE, if the vehicle had ACE, it would have had connections under the passenger seat located by the frame, so I can't tell you what it is for.

 

I do not have SLS or ACE is this pre-wiring for one of those systems? I'm just worried that I have a missing sensor.

 

If you don't have any trouble codes for anything, you're not missing a sensor. My truck has a plug near the transmission that goes to nothing. If there's no problem with the truck, I wouldn't worry about it. I see this sort of thing on all sorts of vehicles.

 

I do have a recurring code.

 

If you had had ACE the car would have had, lower and upper Accelerometers which are two of the ACE system components. The upper one would have been located behind the front interior light and the lower just about the front passenger (US) side outrigger, just where that unused plug is.

 

I just said no ACE.

 

I KNOW YOU SAID NO ACE , if you read what I said again, I said that if you had had ACE, you would have had an accelerometer that that plug connected to. As you don't have ACE the plug is therefore redundant, OK.