Where to get tow wiring
 

Hi all,

I recently purchased a 2003 X5 and intend to use it for towing a pop-up trailer. The car already came with factory hitch, but the PO cheaper out in the wiring and installed a 7 pin connector but no trailer module. When I plug in my trailer, I get a "Check brake lights" message on my dash which I assume means they spliced into the brake light wires for the trailer harness, and the lighting control module doesn't like that. (This is my first German car though and I could be misunderstanding.) I haven't traced the wires from the trailer connector yet, but did look in the trunk and there's no trailer module or any wiring coming in where it should.

I'd just spend the money on the OEM module and harness but it appears the harness is discontinued. I've already called around to a couple junkyards which have X5s on site and haven't had any luck.

I'll need to get a brake controller as well and have seen the recommendations for the Tekonsha prodigy units. I'll certainly pick up one of those but probably need to figure this out first.

Any recommendations are appreciated. Thanks.

I was always under the impression that if you bought a factory hitch, it came with the factory module and wiring?

Are you sure it's a factory hitch?

I thought that wad odd too. It says westfalia on it and but also has a BMW part number. Now that I think about it, I had heard that westfalia made the OE hitch but maybe this one was purchased from westfalia directly. I have a receipt from the PO for installation after the car was purchased in 03 and it did not come from the factory that way.

:worthless:

Show us what you have currently so we can try and help!

I went back and looked at my hitch pictures. It has 71606760080 part number on it and says westfalia and BMW. Thst is the OEM hitch from what Google tells me. The wiring connector however is from Hidden Hitch.

I can try to trace the wires from the hidden hitch seven-pin connector tonight, but I know they don't go to the factory spot in the trunk, nor do I have the factory module. I also get the aforementioned brake light warning when I hook up my trailer. Additionally, the brake lights work fine but the running lights are very dim.

I figure I can fix both of those problems with the OEM module and seven pin connector harness from BMW, but only the module is available. Do any of you know where you can find the harness anymore?

Alternatively, any other suggestions are appreciated. My plan if i can't get the OEM equipment is to just wire in the Tekonsha and deal with the brake light warning. Thanks for your help.

Ben

When you check in the trunk where the factory wiring is, see if it still has the blank (no wires installed) plug attached. If it does you can get the pins / sockets that fit in the harness at the dealer. Then just build it yourself. You already need to get pins for adding the brake controller. Then you just need to source the control module, ebay all day. When I did mine my X recognized the trailer module with out coding but some have not had the same luck as I did. :rolleyes:

Ok, I get it... and I did see the connector for the tow module back there and some other connectors.

I saw you can get the individual pins for that particular connector, but where would I find out what connector to use and where to buy? I'm comfortable building a wiring harness but I would just need the connector.

Did some more searching on this site and google tonight, looking for a part number or source for the actual plug that came on the OEM BMW tow connector harness. No luck.

Looks like I can buy the tow control module ($150-ish from ebay or $250 new) and splice into the harness, or just wire up my controller into my existing tow hitch wiring and deal with the "check brake lights" alarm on the dash when I'm towing.

Pretty disappointed that it is this much of a hassle. But oh well, I like the car enough to overlook it. Thank you all for the help.

This is to add the brake controller wiring to the body side plug
https://www.ecstuning.com/Search/Sit...970/ES2710970/

These are what you need to install on the trailer side plug (the blank housing in your X) and re-route your current hitch wiring to
https://www.ecstuning.com/BMW-E53-X5-N62_4.4L/ES165408/

You will need the Trailer Control Module as well.

Yes... The problem is I do not have the OEM connector that plugs into the trunk wiring and goes to the trailer connector on the hitch. I can add pins and wire the brake controller up to existing side of the connector, but I can't get a hold of the other side connector that plugs into it. And I can't just crimp a pin on some wires and stick the into the connector without the plastic body.

This is the part that I don't know how to find: https://www.ecstuning.com/Search/X5_Harness/ES185391/

I could assemble it if I could find the individual connector that plugs into the other side in the trunk.

Thank you for your help!