Trailer issues
 

Attempted to connect a trailer to my 01 X5 yesterday and for some reason I was not getting any output from the wiring harness, so the lights for the trailer would not work. Took my X buy SA BMW to see if they could troubleshoot the issue but they were too swamped to look at it, told me it would be next week before they could get to it. Had to end up paying for another month of storage for my 740 and leave it in SA and head on to Alabama. I will try to get it scheduled in Alabama to get it fixed so I can pick up my 740 next month. Would anyone have any suggestions on what to do, the U-Haul guys thought possibly a fuse was blown....

Sorry for your trailering woes...... You didn;t say what kind of a connector you had on your vehicle. Are all of the pins at the vehicle receptacle dead? Have you used the connector before and it was fine when you used it last?

I have the factory setup on my 2002, with the factory Pollak connector. This is the adapter I use and it works like a champ.
Pollak 7 Pole to 4 Pole Connector Adapter PK12716 : Trailer hitch bike rack and trailer hitches - etrailer.com

Another good thing about my setup is that one of the pins is an "AUX" which is hot all of the time. This means you can trickle charge the vehicle battery without having to lift the hood using this same kind of a connector.

And, BTW is is NOT the generic 7-blade connector found on the shelf at Autozone..... pins and locking hub are different. Dan

does not look exactly the same but one end is the same round seven connector end and the other is the four way connector. It is about a 6-inch long single rubber piece, I got it directly from U-haul... I will have BMW look at it here in Alabama. It was working a few years back, I do not use it all that often...

I've used the same adapter as n2red to pulll UHauls in the past. Has always worked fine for me. My hitch and wiring are all factory BMW stuff.

If all the contacts in the receptacle were truly dead, meaning no blinkers, brake lights or running lights, then I have to think there's a dead ground somewhere. But I don't know if you were trying to make the trailer lights work or if you were using a circuit tester to test each contact in the X5 receptacle itself. It none of the contacts at the truck were working, try running a new ground wire from the plug to the chassis.

But if you and the UHaul guy were trying to just make the trailer lights work and couldn't, then I would have to say the trailer wasn't grounded to the truck at all. I've had UHauls where I had to physically run a ground wire from the trailer to my hitch rather than rely on the ball and coupler as the ground contact.

Regardless, my first place to check would be for a ground.

If you have an OEM wiring harness you may want to check the back side of the wireing harness which you can get to by removing the plastic piece underneath the bumper that has air scoops in it Ibelieve. On my X the connector and harness had separated and I didn't figure this out untill after a long time and had purchased a new trailer light contol module.

Thanks for the responses, something good to look into....

@TowX, you are right the U-Haul guy was just using the ball joint as the grounding point and he did break out a circuit tester but did not try to find a different ground.

@Dubz, you may be on to something because that plastic piece you are referring to keeps dropping down....