Trailer wiring - OEM harness issue - no power for lights or brakes?? brak
 

I recently picked up a BMW oem trailer hitch and 7 terminal wiring harness (labeled POLLAK on the flip up door) from the upullit yard here. I have a 2001 X5 and it was in a 2002 X5. When installing into my 2001, I found the same original plug in my trunk area (it had an empty plastic plug end in it to keep it from being accidentally grounded and to keep it clean), but the only power I can read in that plug is the always hot terminal, and the ground. None of the other lights have any output there. Is there something I'm not doing right? I have not been able to find an installation guide anywhere online, so I was hoping someone out there might know if I need to add fuses somewhere, or flip a switch or hook up another harness connector. I did notice a white connector up in front of the spare on the right that looks to have the same type of connector as the black one in the rear, but it's too far away to be the one for the trailer harness.

Pretty sure there is a module you need also.

Hopefully someone that's done that will chime in.

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HaHa. I actually had gotten the module that same day without even knowing what it was..Not my first rodeo with BMW in that way. thx zuk for the reply so quickly. I'll dig that module out of my parts bin and give it a try.

Did you get all the other pieces to the hitch ? There are like 8-10 pieces altogether..like the bumper reinforcement?

Yep ... There is a lot there. Make sure you have every piece. I found a couple of bolts had never been installed on my OEM hitch.

I took a look at the back of my 2001, and it appears the hitch takes the place of the bumper shocks. I took the bumper off of the 2002 at the yard and set it aside to remove the hitch itself, so it should still be there if I need anything else. I don't know if I got everything I should have, but I got:
1) the hitch itself and the 8 bolts and nuts that hold it on (nuts are in front)
2) the 2 mounts that hold the bumper on (with the 2 big T55 torx)
3) the wiring harness
4) the control module
5) the mount for the wiring harness with 2 bolts to hold it on

Is the bumper "reinforcement" (that's the metal part inside the plastic bumper cover, right?) different than the one I have now?

Anything else I need to check? thx

https://xoutpost.com/attachments/x5-...-hitch-kit.jpg

I have linked a picture above

You DO need the long bumper reinforcement you left behind. It is different on x5’s with/without the factory hitch

I also want to make sure you have the two heavy brackets that insert into where the bumper shocks go. They are bolted from the rear AND underneath. Maybe they‘re currently attached to the used hitch you have ?

looks like I'm going to visit the u-pull-it yard tomorrow to get the other parts in the photo. thx for the info.
Do you know if there is anything else I should get while I'm there (like an ATF cooler that might be included as part of the factory tow package) that I should look for?

Pretty sure the ATF cooler is standard on all E53....

And yeah, you won't get any power to the trailer without the module plugged in.

I've put the module in and it seems to be working. do you know if it will work electric trailer brakes? The legend on the flip up cap does say "electric brakes" on one of the 7 terminals, but I wondered if I'll need to install one of the under dash trailer brake controllers like on my older truck.

No electric brakes - you need to add a brake controller if you want electric brakes.

It will not work for trailer brakes. The harness is wired for it (blue wire), but the corresponding plug on the car side is empty. X5 trailer module is not wired for trailer brakes. Search the forums. People have added aftermarket elec trailer brake modules.

And if your trailer has LED lights, they may flicker when the car is turned off with the X5 trailer module/ set-up. You will need to turn off "cold monitoring" with PA Soft, or NCS...or install a traditional non-led light somewhere in the trailer light circuit..

Also make sure you get the 2 butterfly-shaped black support brackets (a little larger than your hand) that sit on the inside of the X5 near the spare tire. They are different left to right. At least two of the bolts from the hitch bolt to the inside of the X5 with these brackets.

Since you are there, you might as well grab the climate control module from the center dash if present. They are starting to fail on us.