1. This site uses cookies. By continuing to use this site, you are agreeing to our use of cookies. Learn More.

How to trick Car's Computer Into Trailer Attached Mode?

Discussion in 'Audi S4/A4/A4 Cab (B7 Chassis)' started by MarkJ, Jul 25, 2013.

  1. MarkJ
    Offline

    MarkJ New Member

    Joined:
    Jul 23, 2013
    Messages:
    4
    Likes Received:
    0
    [Jul 25, 2013]
    2008 A4 B7 Avant

    Is there a way to activate the car's computer into tow mode when using a bypass relay for lighting? The computer has been enabled for towing, but by using the bypass relay instead of the dedicated Westfalia towbar wiring harness, the car won't know when a trailer is attached. The Westfalia wiring is still in place, but the trailer will be connected to the bypass electrical connector.

    Thoughts?
    #1
  2. Ads

    Ads

    [Dec 29, 2014]

  3. NHN
    Offline

    NHN Retrofitter - Audi - VW - Skoda - Seat Site Sponsor VCDS Map User

    Joined:
    Jan 14, 2008
    Messages:
    27,515
    Likes Received:
    1,276
    [Jul 25, 2013]
    Usually the car is coded for the towbar module & the module itself sees a connection & thus tells the car what to do, but you don't have a module afaik that's connected to the cars network.
    #2
  4. MarkJ
    Offline

    MarkJ New Member

    Joined:
    Jul 23, 2013
    Messages:
    4
    Likes Received:
    0
    [Jul 25, 2013]
    Thanks very much for your response.

    I also have the dedicated Westfalia towbar wiring harness installed and have enabled the tow module in the computer by entering the code. Additional background on my scenario can be found here. Is there a crossover wire I could add to the Westfalia tow bar plug, or somewhere else, that activates tow mode as needed since everything else is in place and coded correctly?

    I seem to be the only person in the U.S. that has come across the issue with the Westfalia harness and/or is trying to leverage the towing capabilities of the A4 Avant via the computer (which I find hard to believe).

    Thanks!
    Last edited: Jul 25, 2013
    #3
  5. NHN
    Offline

    NHN Retrofitter - Audi - VW - Skoda - Seat Site Sponsor VCDS Map User

    Joined:
    Jan 14, 2008
    Messages:
    27,515
    Likes Received:
    1,276
    [Jul 25, 2013]
    Unless the relay kit has a module that interfaces with the cars network, then its isn't going to happen, as the module connects to the cars network to tell it when something is plugged in, thus disables PDC & lights up on the dash aswell.

    I also cant imagine westfalia didn't think about the pdc side of things, unless the relay kit is specifically for cars without pdc.
    #4

Share This Page