bmwrt

Last week I installed the factory trailer hitch I got from a Florida Audi on Ebay. Nothing like the factory stuff... The problem I had was after connecting the harness and module provided, I had no brake lights and the computer was falting both the entire system. Took to the Stealer and they did the dignostic test. First they thought I had a bad control module so they ordered a new one. Upon further investigation, they decided to look at another Q7 that had a hitch to compare the module coding numbers and they saw it was different from mine. So the new code used was 0200000000000000. Now it works perfect!

Make a note of it if you DYI.

iconoclast

the dealer part is not the same as the factory part and you're losing the additional cooling equipment found on tow package equipped Q7.

don't forget to code your rear view camera and pdc to reflect trailer hitch. step by step retrofit for anyone interested or just for nostalgia sake storing it in the archives:

Trailer Hitch Retrofitting (4L)

These instructions may not cover mechanical/electronic details, they will only list the the diagnostic side (coding etc.). Additional details for the mechanical/electronic work needed are part of the retrofitting instructions provided by the parts supplier (i.e. trailer hitch retrofits) or can be found in the factory repair manuals and wiring diagrams.


Installation & Wiring

Information regarding the Installation can be found in the Repair Manuals, the Wiring Diagrams, the Parts Catalog and/or the Instructions included in the Retrofitting Kit.


Configuration

The following Activations are necessary to ensure that the newly fitted parts are properly recognized and are ready to use.

Update the Installation List in the Gateway (J533 / #19).
Register the newly added 69 - Trailer Control Module via the Installation List Function.
Update the Trailer Control Module (J345 / #69) Coding.
Not all Retrofitting Kits contain Diagnostic capable Trailer Control Modules, some Aftermarket Modules may even be pre-coded. This Step can be ignored for Modules which are not Diagnostic capable.
Due to different Control Modules and Equipment in the Car the actual Coding Table is not shown here but will automatically be used by the Long Coding Assistant once you access the Function using VCDS. If an Aftermarket Module is installed, check the Retrofitting Kit for further Instructions.
Update the Engine Control Module (J623 / #01) Coding.
Make sure that the Engine is NOT running, otherwise the new Coding will be rejected. Models equipped with Start/Stop System do have a Shutoff Switch/Button which will deactivate the Start/Stop Function.
For Engines with a 2nd Engine Control Module (J624 / #11) this needs to be coded as well.
As a Rule of Thumb, If the Engine uses conventional Short Coding (Coding is 7-digits like 0011312) the Long Codding Assistant does NOT apply. Modules using Short Coding typically do NOT support or require Trailer Configuration Coding. If the Engine Control Module uses a Long Coding the Activation is done in (Long) Coding itself through via Coding Assist. Please also note that there are different Coding Variants for Long Coding.
Due to different Control Modules and Equipment in the Car the actual Coding Table is not shown here but will automatically be used by the Long Coding Assistant once you access the Function using VCDS.
Update the Brake Electronics (J104 / #03) Configuration.
To enable the Trailer Stabilization Subtract 0000016 from the existing Coding (e.g. 0033937 - 0000016 = 0033921).
Additional Information may be shown once you access the Coding Function using VCDS.
Update the Level Control (J197 / #34) Coding, if installed.
Due to different Control Modules and Equipment in the Car the actual Coding Table is not shown here but will automatically be shown once you access the Function using VCDS.
Update the Parking Aid (J446 / #76) Coding, if installed.
Due to different Control Modules and Equipment in the Car the actual Coding Table is not shown here but will automatically be shown once you access the Function using VCDS.
Update the Rear View Camera (J772 / #6C) Coding, if installed.
Due to different Control Modules and Equipment in the Car the actual Coding Table is not shown here but will automatically be displayed once you access the Coding Function using VCDS.
Update the Lane Change Assist (J769 / #3C) Coding, if installed.
Due to different Control Modules and Equipment in the Car the actual Coding Table is not shown here but will automatically be displayed once you access the Coding Function using VCDS.
Update the Distance Regulation (J428 / #13) Coding, if installed.
Due to different Control Modules and Equipment in the Car the actual Coding Table is not shown here but will automatically be displayed once you access the Coding Function using VCDS.


Trailer Hitch Retrofitting (4L) - Ross-Tech Wiki

Audi A6 (4F) Parking Aid - Ross-Tech Wiki

bmwrt

Thanks for all the info.

K Lopato

Hi can you give me correct coding for electric hidden towbar ? Everything works fine apart from buttons in boot area to show/hide tow bar. When I press the button it only flashes but nothing moves. Towbar works as I've check it by putting 12v direct to motor. Thanks

bobsyouruncle

Hi, I know this is an older post but did you end up working out what was wrong with your kit? I have a similar issue and can't work out what is wrong.

MattAfro

Same here... Any answers?
I'm getting hitch warnings, says no or incorrect basic settings

bobsyouruncle

Hi, I had to take it back to the dealer, however I believe it was a software issue which they fixed a nil cost to me. Sorry I couldn't help further.

'10Q7TDI_Prestige'

We don't have the electric swivel hitch or the click-in detachable style hitch here in the USA, and neither of you provided any real details about your car or prior use of the towing setup on car, etc.

Therefore, I say go back to square one for your specific car (read the owner manual on proper use of the electric swiveling hitch option you have on car to verify the process; sometimes things that move require one to hold a button to actuate it, or it may require an additional precursor step, etc. If that yields no fruit, then scan the entire car for internal trouble codes using a VAG-compatible scan tool. And lastly, just search the internet using specific search terms related to your car model and any error code, or simply a 'how-to-use' said feature or troubleshoot said feature.

Good luck, and be sure to post up your results once you figure it out.

jbain2

There is a coding option in long coding for the tow hitch that allows you to select that style of hinged hitch. Wondering if that's what is needed for those in question?

MattAfro

i think thats the answer, but i use vcds and i cant find any help with it.
the problem is i cant take it to a audi dealer as im in australia, the car is an import, never had electronically swiveling here at that time so they cant code it.

2007 q7... i know it works, as i can bridge the wiring and it goes in and out, so i can make it work with relays etc, but i want the error code gone.
even unticking the trailer option in the central electronics still shows up the fault on the dash.

any ideas ill take them on board.

weird there isnt much diagnostic support out there, especially weird as its an older car.

-matt