2006 X5 Trailer Brake Controller
 

Did tons of searching and this site was really helpful but there is still one thing I am not sure of.

I have all my wiring and hitch installed and everything works thanks to xoutpost.

One item remains and I am still not clear about it. I believe the issue is that all the other installs are for earlier model X5s. I am looking at my LCM where people here have recommended tapping into for the brake controller and I am looking at the top set of wires and I don't have a black/yellow wire in Pin 10 of connector X12, its a different color. On the set of wires on the white harnass there is a black and yellow wire but that one isn't the top black wire harnass. I was able to find a wire but it provides 6 volts when off, 12 volts when the brake is pressed. I am waiting to hear back from etrailer on whether having 6 volts always on affects the brake controller. If it doesn't than I am set.

Is there is any source when I can get 0 volts when the brakes aren't pressed and 12 volts when the brakes are pressed? Should I tap into the 3rd brake light at the back on the hatch?

Any help appreciated.

For a 2006 model, has anyone tapped a wire for the brake controller

If I was going to do it, I'd probably get the Prodigy wireless brake controller.

I have the wireless prodigy controller. I also used the 7 pin OEM wiring kit and control module but upon closer inspection. My existing harnass that I connected to the OEM 7-pin connector didn't have the pin for the brake controller(blue wire). So I have to find a brake wire for the blue OEM connector.

I think ill jusr probe every wire the LCM until one shows no volts off, 12 volts when the brakes are pressed.

I haven't installed an electric trailer brake controller on an E53, so don't have any specific help to offer. I see the logic of testing each output of the LCM but wonder if there is a risk of putting a test light on a circuit with a multiplexed data signal and potentially damaging something.

You may want to click on the Online References tab at the top of this page next to the FAQ, pick the BMW WDS wiring diagram application that is hosted there for the E53, and see how the wire numbers and wire labels vary between early production models and 2006 models. You should be able to contrast the two and figure out which wire you need. I can't easily use that application on my current laptop, but it would be worth a try IMO. Good luck.