Trailer Hitch Retrofitting for Audi Q7 (4M)

From Ross-Tech Wiki

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. See: Official Factory Repair Information

Software Version Management (SVM)

Software Version Management (SVM) is a system used by VW/Audi to update control modules and in certain cases, to change their Coding.

Note: At the time this wiki page was created, an SVM code has not been published for the [4M] Trailer Kit. Without an SVM Code, the CARPORT database (The manufacture's database of saved vehicle configurations) will not updated when this procedure is performed with ODIS and a valid SVM code. If the vehicle connects to the manufacture and the Actual vs. Specified test plan is run, ALL the coding changes made will be set back to the last known good configuration as per the CARPORT database records.

To make it easier to recode the vehicle when this happens, we recommend to Save a complete vehicle Auto-Scan after all the coding changes have been made for future reference.

Configuration

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

The use of a current generation Ross-Tech interface is necessary. You will need to use the HEX-NET or the HEX-V2 in order to communicate and make coding changes on some of the controllers of the Audi Q7 [4M].


Make sure to enter a Plausible WorkShopCode (WSC) like 12345-123-12345 on the Coding Screen. Control modules with WSC 00000-000-00000 stored can result in rejected coding or a 01042 - Control Module Not Coded Fault Code that will only clear if the WSC used for Coding the Module is NOT 00000-000-00000.

  • 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 maybe rejected.
    • 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 Cent. Elect. (J519 / #09) 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 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 used by the Long Coding Assistant once you access the Function using VCDS.
  • Update the Instruments (J285 / #17) 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 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 used by the Long Coding Assistant once you access the Function using VCDS.
  • Update the Central Conv. (J393 / #46) 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 used by the Long Coding Assistant once you access the Function using VCDS.
  • Update the 6C: Back-up Cam. (J928 / #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 used by the Long Coding Assistant once you access the Function using VCDS.
  • Update the Trunk Elect. (J605 / #6D) 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 used by the Long Coding Assistant once you access the Function using VCDS.
  • Update the Chassis Control (J775 / #74) 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 used by the Long Coding Assistant once you access the Function using VCDS.
  • Update the Frt Sens. Drv. Assist (R242 / #A5) 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 used by the Long Coding Assistant once you access the Function using VCDS.



If you are having trouble finding/calculating the proper Coding using the Long Coding Assist please Register and post in our Retrofitting sub-forum. Make sure to include a complete Diagnostic Protocol (Auto-Scan) from the Car and state which steps/work you have performed.