I recently pulled my seats and carpet due to a cabin water leak. After I fixed the leak, dried and reinstalled the carpet I ran into an issue with the passenger seat wiring. There is a large black wiring connection (no problem with that) and a small white connector coming from the seat. I couldn’t recall if the small white plug is used or not. I didn’t see a wire, so I finished installing the seat. Now I’m wondering if that wire was there and I mistakenly carpeted over it. To solve my problem I’ll need to pull the seat back out and pull up some carpet and look closer for it. The basic question is: does anyone know if that plug is unused on my 2005 s40?

 

I don't know about the wire you are inquiring about under the seat. I see you stopped your water leak. How did you stop it? I have an 06 S40 that is leaking in the rear floor area. Sunroof, A/C drain been checked and ok for what i can see. Also i have a crack in my windshield from end to end and i'm wondering if that could be the problem or part of the problem? thanks

 

My car had a couple of things going on. The drivers side rear carpet was soaked and the headliner was failing and in need of replacement. I’ve had sunroof drain clogs in the past and was relatively confident the leak was coming from that system. I pulled the seats and carpet (along with the center console, which was rather easy). With all of that gone the headliner came out of the passenger side front door with ease. With all of that gone I was able to soak the car slowly from the bottom up and look for leaks. I apologize if this get wordy, but here goes. The sunroof drains run from all four corners of the internal gutter. If all four drains were capped the gutter would simply fill and spill over into the headliner. In my case I found water coming through my sunroof at the point in the rear edge where the gasket comes together. The gasket must have shrank slightly over time creating a gap of about 3/32”. When I had finally worked my way up to the sunroof and from each low corner to the top center and let the hose flood over the entire roof, water started to drip into the gutter at a decent rate. Up to that point no water had made its way to the drivers side floor, which was a bit of a letdown. I was hoping to see a flood from somewhere. Anyway, my car parks on a spot that is slightly angled enough to send the water to the rear drivers side drain hose, and it was clogged. I pulled each drain line from the gutter and blew through them to make sure they were clear. I masked off the sunroof gasket and used silicone to fill that gap. The front divers side drain hose also ended up have a problem that might have allowed water in if the car was setting perfectly level. When I blew the hose I could hear air rushing out of the hose at the connection down by the dash. I really couldn’t get in there to see the problem, but the hose was off fitting that goes through the firewall. I reinserted the hose into the fitting with silicone to seal and hold it. All is back together and dry .... so far anyway.

Let me get back to my question if I may. Under the passenger seat is a large black electrical connection with one small spring loaded bolt holding it together. If you look under the seat it’s easy to see. Besides that there is a smaller white electrical socket connector coming from the seat that on my car has no wire coming up to it. If you look under your seat can you see if it’s used or left open. Maybe it has a use for a feature on a more loaded model.

 

do you have power seats on both sides? If not, my guess is the harness is there for the power seat module...

 

Power on drivers side only.

 

yep, my thought is that the unused connector on the passenger side is the pre-wiring for an upgrade for models with a passenger side power seat.

 

This connector is coming from the seat. The drivers side power seat has a bolt on controller module mounted on the side of the seat. The wires leaving the module go to the adjustment motor. I thought it had something to do with the passenger weight sensor for the airbag. Im getting a airbag error message on the dash, but from what I have been reading that could come because I didn’t disconnect the battery before I pulled the seats. Sorry to be so confusing. I should just pull the seat and carpet back out and dig for wire. If there’s absolutely no wire anywhere in the vicinity of that plug ... I’ll call it a day and clear the code.