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

Electrical issues

Discussion in 'A4/A4 cabriolet/S4 forum(B6 chassis)' started by Hangn69, Feb 1, 2010.

  1. Hangn69

    Hangn69 New Member

    Joined:
    Jan 29, 2010
    Messages:
    5
    Likes Received:
    0
    Having strange issues with my 04 avant last couple of days.Everytime I switch my headlights off the tailgate opens.If I press the lock button next to the drivers door handle before I do this it doesnt open the tailgate.Anyone have any ideas?
     
  2. Google AdSense Guest Advertisement



    to hide this advert.
  3. Woorlord

    Woorlord shifting to Hyperspace... .
    VCDS Map User

    Joined:
    Dec 8, 2007
    Messages:
    949
    Likes Received:
    13
    Strange combination of faults?

    "Power control unit" (PCU) deals with the headlights and the "Convenience module" (CM) deals with the locking/alarm etc., all interfaced to the door switch by CAN-BUS.

    PCU under steering wheel to lower right on RHD car.
    CM under front passenger seat.

    Does your remote open the tailgate OK?

    Perhaps a short in the loom between signals for tailgate lock and rear lights - may be worth tracking the loom and check for possible shorts or damaged wires?
    Looms should run under the internal plastic covers on top of sills - however would have thought lights and locking signals run on different sides owing to module locations.
    Therefore, one would assume possible wiring fault where the two wires merge together - maybe in the tailgate area - number plate lights and wire to lock motor probably close to each other??
     
  4. Hangn69

    Hangn69 New Member

    Joined:
    Jan 29, 2010
    Messages:
    5
    Likes Received:
    0
    opens normally with remote ,works fine in every way.Just opens when I turn headlights off.I have replaced the lock mechanism recently as the microswitch inside was gone but it worked fine only the last couple of days its started acting up.
     
  5. Hangn69

    Hangn69 New Member

    Joined:
    Jan 29, 2010
    Messages:
    5
    Likes Received:
    0
    update ,when I turn headlight switch off the lock actuator/rod is opening the tailgate, not the alarm/microswitch.Also while trying to solve this problem I have found that if I disconnect the harness plug from the back of the headlight/sidelight switch with it in the off position and turn the ignition to on but not start the headlights and side lights are all on,is this normal?
     
  6. NHN

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

    Joined:
    Jan 14, 2008
    Messages:
    28,051
    Likes Received:
    1,396
    Would seem to be correct from a safety view, as if it doesnt detect the switch, then its better to have them on at all times as it doesnt matter if there on during day & better safe than sorry if the headlight switch failed at night huh, probably a default feature
     
  7. J7USS

    J7USS Shuddup Foooool!!

    Joined:
    Oct 25, 2006
    Messages:
    3,683
    Likes Received:
    2
    "Autobots Stand by"... :scared2:
     

Share This Page