2007 Trailer Hitch and Wiring Harness

[paul1994]

Ok.. I noticed on etrailer dot com that they have there own wiring kit . has anyone used it?

And what are the reason to have the dealer program it with a OEM harness rather than a after market one. I assume you don't have to have the truck programmed if you use an aftermarket wiring harness

Here is a link to there install.

Tow Ready Custom Fit Vehicle Wiring,Wiring for BMW X5 2010 - 119190KIT

[JCL]

If you use the OE harness, then the vehicle is aware of the trailer being connected electrically. That means that you get bulb out warnings, the LCM monitors the lighting circuits, and when you put it in reverse the vehicle disables the rear PDC, which would otherwise beep every time you select reverse, since it thinks you are about to back into your trailer.

[paul1994]

Originally Posted by JCL

If you use the OE harness, then the vehicle is aware of the trailer being connected electrically. That means that you get bulb out warnings, the LCM monitors the lighting circuits, and when you put it in reverse the vehicle disables the rear PDC, which would otherwise beep every time you select reverse, since it thinks you are about to back into your trailer.

Thanks for the responses JCL.. This all makes sense, but can't you just turn off the PDC ( By pressing the Button) when reversing to turn it off? Knowing the Lights are out I can deal with. I guess my only concern is if I take it in to the dealership and they say splicing into the wires are a problem.

Since I am out of warranty and I usually go to my independent shop. I think I might go this route if All I am missing is the light circuitry and to turn off the rear PDC.

One more question is there a anti sway module as part as the OEM wiring kit?

[JCL]

Originally Posted by paul1994

Thanks for the responses JCL.. This all makes sense, but can't you just turn off the PDC ( By pressing the Button) when reversing to turn it off? Knowing the Lights are out I can deal with. I guess my only concern is if I take it in to the dealership and they say splicing into the wires are a problem.

Since I am out of warranty and I usually go to my independent shop. I think I might go this route if All I am missing is the light circuitry and to turn off the rear PDC.

One more question is there a anti sway module as part as the OEM wiring kit?

Yes, you can just turn off the PDC.

Splicing into the wires has worked fine for some. For others it has caused error messages and problems in the LCM. If you don't get any error messages then it will be fine. If you do, then remove it. It has nothing to do with warranty.

BMW designed an integrated system. The parts are designed to work together. It is their corporate philosophy. If you don't value that integration, then you shouldn't pay for it. Personally, I think that not using the OE trailer wiring is like using an aftermarket FM radio. It may work, but why bother?

I agree with the poster above that there is no sway logic in the trailer wiring module. It is in the DSC. However, I am not sure that it needs the trailer module to be connected to function. It may. But it also may work just by sensing a particular set of signals from existing sensors, which cause it to use the trailer sway algorithm. It doesn't actually do anything to the trailer brakes, it just uses the vehicle brakes to counteract sway. If my vehicle swayed without a trailer I would want exactly the same response from my DSC, so that is the way I would design it. But it may actually check that there is a trailer electrically connected. I don't know. I do know that my X3 has trailer stability control, and didn't require any coding or the vehicle order to be modified.