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Hazard lights stuck on.

Discussion in 'A4/A4 cabriolet/S4 forum(B6 chassis)' started by AlexGSi2000, Jul 31, 2013.

  1. AlexGSi2000
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    AlexGSi2000 Well-Known Member VCDS Map User

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    [Jul 31, 2013]
    Just wondering if anyone has experienced the same issue as me...

    Basically, my hazard warning lights are "stuck" on...

    I unlocked the car yesterday morning, straight away the hazard warning lights started flashing continuously.
    I thought possibly the alarm was going off and I had a dead alarm siren battery, but it wasn't.

    I started the car, pressed the hazard light button and they went off.

    Throughout the journey the hazard lights would start and go off randomly.
    I thought about possible water ingress due to all the rain we have had lately (plenum drains were cleaned a few months back) - all front carpets.etc were dry.

    When I got home from work, I double checked the plenums and ECU box / seal - all were clear and not showing signs of any water entering the car.

    On the way into work this-morning the hazards were stuck on all the way!
    I pulled over, removed the fuses for the CCM, removed and disconnected the hazard light switch - but they are still on.

    Are there any additional relays / fuses for the hazards, just to make them stop? - the indicators, along with everything else work fine.

    I have thought about the CCM to blame, but it was dry when I checked.
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  3. AlexGSi2000
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    AlexGSi2000 Well-Known Member VCDS Map User

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    [Jul 31, 2013]
    Just had a quick faff about on my lunch break...
    Removed the drivers lower trim panel (below the steering wheel) - pulled a few fuses / relays.etc which didn't stop the indicators.

    Sounded like the relay may be behind the speedo / instruments somewhere as opposed to being on the hazard switch like the B5.

    Removed a few more relays / fuses.etc but the hazards kept on going!

    I resorted to unplugging a few power and wiring connections until the hazards stopped - found out which one it was, gave it a wipe (looked clean and dry) and left unplugged for 30 minutes or so.

    I have plugged them back in and so far it seems to be behaving (touch wood)
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  4. hades-
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    hades- Yorkshire & Humber Rep. Regional Rep VCDS Map User

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    [Jul 31, 2013]
    remove the switch
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  5. AlexGSi2000
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    AlexGSi2000 Well-Known Member VCDS Map User

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    [Jul 31, 2013]
    I did remove the switch - didn't make a blind bit of difference!
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  6. hades-
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    hades- Yorkshire & Humber Rep. Regional Rep VCDS Map User

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    [Jul 31, 2013]
    check for any water round the relays
    there known for leaking through the ecu box
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  7. AlexGSi2000
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    AlexGSi2000 Well-Known Member VCDS Map User

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    [Aug 5, 2013]
    My electrical gremlins are back!

    The hazards have been fine for a few days - along with the rest of the car.

    Went out to the car on my lunch break and I have a single (nearside) reverse light on, hit the unlock button and it goes off!
    The car wasn't even left in reverse.

    Going to have to have a proper trawl through things one evening this week - anyone have any suggestions on places to start?

    Cheers!
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  8. hades-
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    hades- Yorkshire & Humber Rep. Regional Rep VCDS Map User

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    [Aug 5, 2013]
    did you check the ecm for any sings of water

    very comon on the A4
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  9. AlexGSi2000
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    AlexGSi2000 Well-Known Member VCDS Map User

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    [Aug 5, 2013]
    Yeah, I took off the lower cowling - below the steering wheel - all bone dry, passenger carpet is dry.

    Need to have a proper look around by the sound of things.
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  10. hades-
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    hades- Yorkshire & Humber Rep. Regional Rep VCDS Map User

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    [Aug 5, 2013]
    remove the ecm it may have got water in it and you cant always tell
    its the unit with the 3/4 big plugs in it

    to the right below light switch
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  11. AlexGSi2000
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    AlexGSi2000 Well-Known Member VCDS Map User

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    [Aug 5, 2013]
    Thanks bez is it where all the fuses and relays are?
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  12. hades-
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    hades- Yorkshire & Humber Rep. Regional Rep VCDS Map User

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    [Aug 5, 2013]
    sort of

    its at the side of the fuse box above the bonnet release

    3/4 big plugs in it no relays or fuses in it tho

    post a pic and ill point it out for you
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  13. AlexGSi2000
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    AlexGSi2000 Well-Known Member VCDS Map User

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    [Aug 5, 2013]
    Hi bez, found it!

    Took the thing out, as I tilted it on its side, water started pouring out the corner!

    Took the cover off, its been pretty wet. If dried it all out, but I reckon I will need to replace it.

    The part number I have is 8E0 907 279 E.
    My next question is, if I get a newer unit, can I get one with return home lights? (lights that come on when unlocked)?
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  14. hades-
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    hades- Yorkshire & Humber Rep. Regional Rep VCDS Map User

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    [Aug 5, 2013]
    you need 1 from a b6 model only

    iv tried the b7 on b6 and they did not work

    NHN could give you more info on the comeing home lights but thats more sensors etc etc

    next thing is where the water came in ?
    fisrt off is remove the ECU cover as they do let water in the seal goes

    and under the battery pull the bung out if its still in there
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  15. AlexGSi2000
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    AlexGSi2000 Well-Known Member VCDS Map User

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    [Aug 6, 2013]
    Thanks a lot for your help bez - the ECM seems to be working ok now, but there were signs of slight corrosion on the PCB and around a few components, so will keep a lookout for a replacement on ebay.

    The water seems to have definitely come from the ECU box area, the seal and box looked fine, but I used a little roof sealant for the time being before I order a new seal.
    #14

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