Does the Trailer Control Module have to be coded after it was installed with hitch?

[Whitecat]

Here is the BMW instruction
http://www.kneb.net/bmw/E70/Trailer%...-%20towbar.pdf

[upallnight]

I hope people are chiming in with actual experience, there's enough misinformation on the net already, and like the Allstate's commercial, don't believe everything you read on the internet.

I was lucky when I brought my X, a factory hitch was already there.

[TiAgX5]

Originally Posted by upallnight

.......I was lucky when I brought my X, a factory hitch was already there.

Most used vehicle shoppers look for tow vehicles without tow hitches. There's additional wear/tear on vehicles used to tow. The $400 to buy/install a tow package is usually cheaper then correcting the wear items towing effects. I'v seen some images/videos online of X owners towing big trailers loaded with offroad toys down trails I would not subject my X to without a 6000 lb trailer.

[JCL]

Originally Posted by TerminatorX5

interesting - somehow, a trailer module was working fine in the '06 without any programming... i installed it about 6 months ago... maybe because it is a 4.8?

Up to 2003, the instructions from BMW made no mention of coding. On this board, many of us installed hitches (I installed two OE hitches myself, one was a 2007 X3, same trailer control module) with no issues. Starting in 2004, posters began to complain that their trailer modules did not function correctly, and BMW developed a coding solution. All of that history is documented on this and other boards. The published service instructions changed. They then said to code (or flash) the vehicle. This procedure does not install code for the lights or the trailer stability control (both of which worked fine without coding on prior and some later models) it simply overcomes a problem by which the vehicle does not recognize the trailer wiring module. I don't know the particular steps, but they are documented here. I just don't have reason to recall what the GT-1 or similar instructions were. There was a specific set of steps to follow, I do remember that. It doesn't happen in all cases. If you plug it in, and it works, great. But the reason that BMW changed the service instruction is that in some cases, coding was required.

Opinions vary on why it happens to some and not other vehicles. Personally, I think it is because of the specific combination of various modules and options installed on a specific vehicle. I can't prove that, it is just an educated guess. It may be that a newer version of the vehicle software was released at some point that just doesn't look for the trailer wiring module, ie faulty vehicle software. Can't say. But the service instructions continue to say that coding is required, leading me to believe that it wasn't confined to a specific batch, but is rather dependent on the individual vehicle consist.

Your sample of one is no doubt correct, but that doesn't over rule the BMW service instructions or the history of many who have had to have their vehicles coded post 2004.

[JCL]

Originally Posted by Whitecat

Here is the BMW instruction
http://www.kneb.net/bmw/E70/Trailer%...-%20towbar.pdf

Almost, but not quite. That is the E70 instruction, not the E53. That link is valuable, because it describes, for the E70, what programming is required. The steps documented in that instruction say to use PROGMAN 23.2, and change the vehicle order to include the relevant module. That is the software equivalent of forcing a plug and play device to be recognized, IMO. For some reason, the earlier plug and play routine stopped functioning in some (but not all) cases.

There is a problem using the 2006 instruction that you posted. It says that no trailer brake controller is available from BMW. That was true in 2006, but later changed. A later version of that instruction may be of more help for those who plan to tow trailers over 1600 lbs.

http://www.bmwmotorsports.org/pdf/e5...iler_hitch.pdf

This is the instruction for the E53, dated 2000. It was not still valid when I did my 2003 hitch install, from memory, but it was very close. Nothing material. I got the latest instruction printed out by my dealer, and compared them. The one posted here shows the EU hitch (swan neck) but the steps are the same. No mention of any coding required.

I don't have a 2005/2006 version of that instruction, but someone will. I suspect it will have some form of coding instructions, probably similar to your link for the E70.

I did install a hitch on a 2007 E83, which uses the same trailer wiring module. That vehicle also had trailer stability control, cancelling of the rear PDC, etc, suggesting that none of that coding is required to be loaded, it is already on the vehicle waiting to be activated. The service instructions (2009 or 2010 release, can't remember which) specifically stated that for that specific model, no recoding was required, and customers should not be charged for recoding. Apparently the E83 vehicle software, which is based on the E46, didn't have the post-2004 LCI E53 problems.

[JCL]

Originally Posted by TiAgX5

Most used vehicle shoppers look for tow vehicles without tow hitches. There's additional wear/tear on vehicles used to tow. The $400 to buy/install a tow package is usually cheaper then correcting the wear items towing effects. I'v seen some images/videos online of X owners towing big trailers loaded with offroad toys down trails I would not subject my X to without a 6000 lb trailer.

Good comment. I don't have concerns over standard trailers, but I made a point of having my towing history available when I went to sell my E53. How much weight, how far, etc. I wouldn't worry about the trailer weight as much as I would the off-road use, with trailer or without.

[Roadkill]

Thanks guys for all the comments. I suppose I just need to plug a trailer in and see if the lights and electric brakes function.

[JCL]

Originally Posted by Roadkill

Thanks guys for all the comments. I suppose I just need to plug a trailer in and see if the lights and electric brakes function.

If you have installed the OE trailer wiring module, then yes, try the lights. When the trailer is connected, put it in reverse and see if the rear PDC comes on, or beeps continually. That is the easiest test. However, that module has no brake controller, that is a separate device. A brake controller will be aftermarket by definition, and has no coding.

[Roadkill]

Copy, thanks JCL.

[upallnight]

Originally Posted by TiAgX5

Most used vehicle shoppers look for tow vehicles without tow hitches. There's additional wear/tear on vehicles used to tow. The $400 to buy/install a tow package is usually cheaper then correcting the wear items towing effects. I'v seen some images/videos online of X owners towing big trailers loaded with offroad toys down trails I would not subject my X to without a 6000 lb trailer.

The owner of my X used the trailer hitch for a bike rack, so it didn't bother me that there was a trailer hitch on the X.