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I have a 2004 BMW X5 4.4i, I have already installed a trailer hitch and now I am working on installing the trailer wiring harness. I need to find out what wires control what lights. On the factory wiring harness that plugs in to the tail lights there are 4 wire's. Please help Identify what these wire's control.

Driver side plug.

1-Solid Orange
2-Green/Black
3-Green/Blue
4-Brown/Black

Passenger side plug.

1-Solid Orange
2-White/Black
3-Orange/Black
4-Black/Blue
 

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I am looking for the module and the wiring harness but not having much luck (2005 E53) where is the best place? Or even part numbers would be helpful?
 

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With all of the horror stories about aftermarket units I was looking to maybe score an authentic BMW wiring kit, but all of the ones I have found were "no longer available" and many of those were the entire kit - big metal hitch and all.
 

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04 x5 e53 wiring harness - oem - looking for one

were you able to find an oem harness? i could really use one. any leads would be helpful. thank you.
 

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I made my own and bought a trailer control module from ebay for about $45. I will dig up the part numbers and the wire pin for the project once I get home this evening. I have been meaning to produce a nice DIY with part numbers and so on. It's been a back burner project that I have had. But I did a close to OEM install of a trailer hitch wiring harness that I was very happy with.

I ordered female connecting Pins P/N: 61131376204 depending on if you will do a 4 plug trailer connector or a 7 pin. That part is up to your needs and I purchase that trailer plug-in connector assembly from any trailer parts site or store. The rest you just assemble and order the quantity you need for the little internal pins for the electrical connector. You will need grommet P/N: 61138369503 for the pass through wiring from hitch to trunk area (forward of spare tire) were the prewired plug for the trailer wiring is, its Item#2 in my drawing. And you'll want BMW Plug Housing 12 Pol. P/N: 61131378138 item#1 in drawing. to connect to the said prewired plug. Lastly you'll then need Towing Control Module P/N: 61356955253 to complete the OEM wiring install. I did mine this way because I hate to cut or splice into wiring harnesses ;). I'll get the 12 pin wiring schematic once I get home.
 

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I made my own and bought a trailer control module from ebay for about $45. I will dig up the part numbers and the wire pin for the project once I get home this evening. I have been meaning to produce a nice DIY with part numbers and so on. It's been a back burner project that I have had. But I did a close to OEM install of a trailer hitch wiring harness that I was very happy with.

I ordered female connecting Pins P/N: 61131376204 depending on if you will do a 4 plug trailer connector or a 7 pin. That part is up to your needs and I purchase that trailer plug-in connector assembly from any trailer parts site or store. The rest you just assemble and order the quantity you need for the little internal pins for the electrical connector. You will need grommet P/N: 61138369503 for the pass through wiring from hitch to trunk area (forward of spare tire) were the prewired plug for the trailer wiring is, its Item#2 in my drawing. And you'll want BMW Plug Housing 12 Pol. P/N: 61131378138 item#1 in drawing. to connect to the said prewired plug. Lastly you'll then need Towing Control Module P/N: 61356955253 to complete the OEM wiring install. I did mine this way because I hate to cut or splice into wiring harnesses
. I'll get the 12 pin wiring schematic once I get home.
Way above my knowledge of how to do this but thanks for your reply. If I don't have luck you can make one for me! Bought my x5 intending to tow, thus the 4.4 v8, no idea a simple OEM wiring harness would be so hard to find.
 

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I ordered female connecting Pins P/N: 61131376204 depending on if you will do a 4 plug trailer connector or a 7 pin. That part is up to your needs and I purchase that trailer plug-in connector assembly from any trailer parts site or store. The rest you just assemble and order the quantity you need for the little internal pins for the electrical connector. You will need grommet P/N: 61138369503 for the pass through wiring from hitch to trunk area (forward of spare tire) were the prewired plug for the trailer wiring is, its Item#2 in my drawing. And you'll want BMW Plug Housing 12 Pol. P/N: 61131378138 item#1 in drawing. to connect to the said prewired plug. Lastly you'll then need Towing Control Module P/N: 61356955253 to complete the OEM wiring install. I did mine this way because I hate to cut or splice into wiring harnesses ;). I'll get the 12 pin wiring schematic once I get home.
This is awesome. I'm interested in doing this as well.

So you just bought your own wires and ran them between the Plug Housing (61131378138) and external socket (https://www.etrailer.com/Wiring/Pollak/PK11893.html)? Am I following that correctly? What gauge wire did you use?

I'll probably try it without the Towing Control Module (never had anything that fancy on my SUVs before and not going to pulling anything big or often behind the X5 anyways).
 

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Yes you are correct. I bought all the wires, plugs, grommets, OEM connectors, pins and the universal trailer hitch plug. Basically built my own trailer hitch wiring pig tail (harness) installed the trailer module and now enjoy a very clean looking trailer hitch addition. I cant quite recall the gauge of the wires because they came with the universal connector. they were kind of thick, i'd like to say maybe 14 or 16 gauge.
 

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with ALL the horror stories I've heard about wiring the trailer plugs, I sticked to the OEM setup and felt the peace of mind. When I hook-up the trailer, I don't have to worry IF one of the light(s) if OFF or if the parking lights aren't on. nop
And This peace of mind had a price. I bought the OEM trailer hitch attachement with all the wiring AND the module for 1200$ CDN ( 950$US ) on Ebay and it did fit right there no hassle.

That was my experience with this.
 

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This is awesome. I'm interested in doing this as well.

So you just bought your own wires and ran them between the Plug Housing (61131378138) and external socket (https://www.etrailer.com/Wiring/Pollak/PK11893.html)? Am I following that correctly? What gauge wire did you use?

I'll probably try it without the Towing Control Module (never had anything that fancy on my SUVs before and not going to pulling anything big or often behind the X5 anyways).
I sincerely hope that you won't have any issue with the ECU of your X5 because If you search in this thread, you'll find that there is a whole lot of horror stories out-there.
 

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Honestly, I haven't tried it yet.

I don't have a trailer that needs a 4 pins wiring attachement. Only a 7 pins one.
 

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I made my own and bought a trailer control module from ebay for about $45. I will dig up the part numbers and the wire pin for the project once I get home this evening. I have been meaning to produce a nice DIY with part numbers and so on. It's been a back burner project that I have had. But I did a close to OEM install of a trailer hitch wiring harness that I was very happy with.

I ordered female connecting Pins P/N: 61131376204 depending on if you will do a 4 plug trailer connector or a 7 pin. That part is up to your needs and I purchase that trailer plug-in connector assembly from any trailer parts site or store. The rest you just assemble and order the quantity you need for the little internal pins for the electrical connector. You will need grommet P/N: 61138369503 for the pass through wiring from hitch to trunk area (forward of spare tire) were the prewired plug for the trailer wiring is, its Item#2 in my drawing. And you'll want BMW Plug Housing 12 Pol. P/N: 61131378138 item#1 in drawing. to connect to the said prewired plug. Lastly you'll then need Towing Control Module P/N: 61356955253 to complete the OEM wiring install. I did mine this way because I hate to cut or splice into wiring harnesses ;). I'll get the 12 pin wiring schematic once I get home.
Did you happen to ever post the 12 pin wiring schematic?
 

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Bump
 

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Dompie99,
Here is a post I could see on the e-brake matter & Controllers.
https://xoutpost.com/bmw-sav-forums/x5-e53-forum/39158-electric-brake-controller.html
I am not sure if the E53 is quite wired for E-brakes or not. Also you are correct the truck side has only 6-wires. And the BMW branded Trailer connection pigtail has 7 pins, so go figure right. Anyway, in my set up E53 3.0i (US version) I only utilize the following pins on the pig tail end for a 4 pin trailer connector.

fishhouse4,
Sorry it's taken a while to post other wiring pin layouts but have been extremely busy. But here is a little something. It's the pins from the X5 side to the trailer.

Pin# 1 - L/H Turn signal
Pin# 3 - Ground (-)
Pin# 4 - R/H Turn Signal
Pin# 7 - Running Lights

Like I said the truck side has 6 wires, I only utilize 4 on my trailer application so there are 2 unused that I am trying to investigate what they are for. One of the wires is thicker gauge than the others, so I presume it's the 12+ Aux power one. Here is the lay out of the Pins from the OEM 7 pin pigtail as its laid out with part number so anyone else looking can manufacture their own trailer connector if they so desire. I will look tonight and see what pin designation the other 2 pins I referred to are on the X5 end. I know the trailer control module makes all the lights work seamlessly.
The trailer connector is listed as follows on the OEM BMW pig tail. (picture attached)

Pin# 1 (Red) L/H Turn Signal
Pin# 3 (White) -Neg. Ground
Pin# 4 (Brown) R/H Turn Signal
Pin# 7 (Green) Running lights
Pin# 8 (Yellow) Back Up
Pin# 9 (Black) +Pos. (Auxiliary 12 Volts)
Pin# 11 (Blue) E-Brakes
 

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Here are the plugs that are in the connector (X393) 12 pin plug from the X5 e53 3.0i US chassis. As you can see there is no plug in Pin#11 which is were the E-brake would be connected to for the Hitch connector. I supposed if you had a signal coming from a aftermarket unit you could use a 61131376193 (male) BMW pin to insert into pin #11complete the set up. As for the other two I presume Pin#8 is for the back up lights, Ill try and test soon and then Pin#9 Appears to be Aux Power because it is thicker than the other cables. Again will have to verify. ;)

Schematics could be found in https://www.newtis.info/tisv2/a/en/
 

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