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Sudden random major electrical woes

Discussion in 'A4/S4 forum(B5 Chassis)' started by voteforpedro, Feb 9, 2009.

  1. voteforpedro
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    voteforpedro Member

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    wtf is going on with my car today?

    First the ABS light came on while driving this morning. Wasn't too worried, easy enough to rectify.

    Then the alarm started going off for no reason early this evening. I went down just to switch it off again and the clocks were illuminated... odd. The immobiliser light was flashing, the you've-been-driving-for-four-hours indicator flashing, and the interior light was on.

    Took it for a drive to the shop; drove fine apart from the ABS light again. Got back to the car and the indicators were all flashing, probably because the alarm had gone off. Got in, got home and then all hell broke loose.

    The battery light came on, there was a clicking noise coming from behind the clocks until I opened the door and the interior light dulled to very dull but didn't quite go off. Oh, and if I set the alarm it goes off without fail so it is now left opened, unarmed and unlocked.

    wtf?

    Does this have anything to do with the suspected leak causing dampness behind the front passenger seat? I imagine the scuttle tray may be filled to the brim...

    Battery is new and the car starts without fail, so it's not the battery per se. Car drives fine, too.
    #1
  2. Broken Byzan
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    Broken Byzan Photographic Moderator Staff Member Moderator

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    That will be water somewhere there shouldnt be. What about in the boot near the CL motor, or in the footwell some models have a convenience module doesnt it?
    #2
  3. jcb
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    jcb Active Member

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    long stick, behind battery, poke drain hole clear and stand back so you don't get any on your shoes.
    had the same thing with mine.
    thought the leak was at the rear passenger until I checked the front one!
    overflowing scuttle tray, through pollen filter.
    cleared the problem almost straighta way....takes a while to dry out though
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  4. H2o-uk
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    H2o-uk Member

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    A couple of questions arise from your answers for me personally, I have a 1997 2.6 SE , and I founda damp patch in the boot, where is the CL motor ? and also where is the Pollen filter in the front, as I might have an issue there as the windscreen seems to steam up quite often. Any pictures would be handy.

    Thanks
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  5. aragorn
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    aragorn "Stick a V8 in it!" Staff Member Moderator

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    if the windscreen steams up, its liekly the scuttle panel drains are blocked, theres two, one under the battery and one under the brake servo.

    As for the OP, possibly the same issue with water leaking into the central electrics panel.

    B6 A4's have a convenience module in the passenger footwell which gets wet when these drains get blocked, and does what you describe, but i dont think the B5 has this?

    Clear the drains and stick a fan heater or something in the car for a few hours to dry it out, and see how that goes.
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  6. aragorn
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    aragorn "Stick a V8 in it!" Staff Member Moderator

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    if the windscreen steams up, its liekly the scuttle panel drains are blocked, theres two, one under the battery and one under the brake servo.

    As for the OP, possibly the same issue with water leaking into the central electrics panel.

    B6 A4's have a convenience module in the passenger footwell which gets wet when these drains get blocked, and does what you describe, but i dont think the B5 has this?

    Clear the drains and stick a fan heater or something in the car for a few hours to dry it out, and see how that goes.
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  7. aragorn
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    aragorn "Stick a V8 in it!" Staff Member Moderator

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    if the windscreen steams up, its liekly the scuttle panel drains are blocked, theres two, one under the battery and one under the brake servo.

    As for the OP, possibly the same issue with water leaking into the central electrics panel.

    B6 A4's have a convenience module in the passenger footwell which gets wet when these drains get blocked, and does what you describe, but i dont think the B5 has this?

    Clear the drains and stick a fan heater or something in the car for a few hours to dry it out, and see how that goes.
    #7
  8. tazzy baby
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    tazzy baby Rookie

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    Hi there i aint being funny but have you checked for gremlins they are all over my car:haha:
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  9. voteforpedro
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    voteforpedro Member

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    Do I need to remove the servo to clear the hole beneath it? The one beneath the battery was well and truly blocked but because of the camber of the road, the water has collected on the O/S beneath the servo so it is definitely blocked.

    Any tips?
    #9
  10. aragorn
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    aragorn "Stick a V8 in it!" Staff Member Moderator

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    You need to remove the battery, and preferably the battery cradle too for maximum room.

    Then you can get to the one under the battery easily. The one behind the servo is just a case of reaching behind it, in the gap now vacated by the battery, and poking at the drain. Once you;ve got them flowing, i suggest pouring a few large bottles of water down to wash all the silt and **** away.

    The other area **** gathers is around the ECU box and up underneath the wiper motor. On craigs car, we ended up removing the ECU box completely (make sure the area is dry before doing that), and giving the whole area a good clean before refitting it all.
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  11. voteforpedro
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    voteforpedro Member

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    Thanks. Found the plug thanks to this photo:

    [​IMG]

    Although mine has aircon so the pipes are in the way. Yeah, they were both properly blocked. I even found the two huge washers for the top suspension mounts I lost under there. :)

    Both are cleared now and I will pour something like Mr Muscle down there later on. Trouble is, the car now won't start and the electrics are all fucked up. I will try jump-starting it when the missus brings the Corsa back tonight but failing that...?
    #11
  12. Caesium
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    Caesium My BM is fixed!

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    I concur with the above, it sounds like water is definitely getting in, check around the air vents under the front seats to see if that's the ingress point.
    Its probably caused by an excessive amount of leaves in the drain points, which are normally just in front of the windscreen.
    Have a general check around, or take a picture of under your bonnet and I'll tell you what components to remove and check underneath.
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  13. Caesium
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    Caesium My BM is fixed!

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    you must have posted while I was typing!
    I would disconnect the battery and put a heater or if you have one a dehumidifier in the car for a while.
    If water has got into a control module, kiss it goodbye.
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  14. voteforpedro
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    voteforpedro Member

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    While we're on topic, if anybody could find me a price and part number for the plastic scuttle cover the facelifts got, I would be grateful. Did the older B5 Passats get the tray? If so, I might hit the scrapyard soon...
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  15. voteforpedro
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    voteforpedro Member

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    The ECU? I'm hoping the problem is now a dead battery due to erratic behaviour of the dashboard instruments (and God knows what else) over night. Although it did start and drive just fine last night, and I do drive it daily...
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  16. Caesium
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    Caesium My BM is fixed!

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    There are several control modules, when you turn on the key do you get anything?

    If the battery is dead then you'll know easily, turn on the lights and then crank, if they go really dim the battery is dead. If they don't its some other problem.
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  17. aragorn
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    aragorn "Stick a V8 in it!" Staff Member Moderator

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    i often do the headlights trick, but some cars kill them when cranking anyway which makes it hard to tell.

    I find if you flick the interior light on and the lights, then crank, the interior light gives you a nice visual of the batteries condition.

    As i said before i dont know where the electrics are in the B5, i'm sure it doesnt have a convenience module like the B6, but water might have leaked into the central electrics panel behind the fusebox. Defo get a heater or something in there to dry it out (just watch you dont melt or set fire to anything :p), might even be worth removing the carpet and drying it out properly if its really sopping wet...
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  18. aragorn
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    aragorn "Stick a V8 in it!" Staff Member Moderator

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    i often do the headlights trick, but some cars kill them when cranking anyway which makes it hard to tell.

    I find if you flick the interior light on and the lights, then crank, the interior light gives you a nice visual of the batteries condition.

    As i said before i dont know where the electrics are in the B5, i'm sure it doesnt have a convenience module like the B6, but water might have leaked into the central electrics panel behind the fusebox. Defo get a heater or something in there to dry it out (just watch you dont melt or set fire to anything :p), might even be worth removing the carpet and drying it out properly if its really sopping wet...
    #18
  19. voteforpedro
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    voteforpedro Member

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    Headlights/taillights and electric windows work.

    Central locking doesn't work. The interior light, dashboard lights, clocks, instrument lights and aircon display flick on and off repeatedly. Car doesn't even try and start - the starter motor just clicks.
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  20. aragorn
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    aragorn "Stick a V8 in it!" Staff Member Moderator

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    do the lights dim when it clicks?

    The dashboard etc flashing like that sounds like one of the main relays in the central electrics panel is gubbed...
    #20
  21. voteforpedro
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    voteforpedro Member

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    Possibly caused by water ingress? :keule:
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  22. voteforpedro
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    voteforpedro Member

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    Lights switch on/off repeatedly with key set to "on" and all lights go off when starter motor is clicking away.
    #22
  23. aragorn
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    aragorn "Stick a V8 in it!" Staff Member Moderator

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    if the starter is clicking rapidly, kinda like a machine gun, the battery is simply flat.

    Give it a proper charge and see if the problems go away.
    #23
  24. Broken Byzan
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    Broken Byzan Photographic Moderator Staff Member Moderator

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    ^^ i agree ^^

    A good charge and a dry out hould fix most of the problems
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  25. voteforpedro
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    voteforpedro Member

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    So... I charged tbe battery a bit and came back to life. Took it for a test drive, ABS light came on again. Got back home and the alarm went off again and the dashboard lit up and flashed like Blackpool illuminations again,

    Alas, I suspect the battery is dead again today and now I have no means to get to uni as the missus has the other car.

    ffs.

    I got a heater from Freecycle so I'll get that in there today. Hopefully the electrics are just a bit "damp" still. Failing that, what gives? I can't be charging the battery every day, must find the fault...
    #25
  26. aragorn
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    aragorn "Stick a V8 in it!" Staff Member Moderator

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    hmm, the flashing dashboard might just be because the battery is flat?

    If theres one relay that controls the main power to the dash electrics, you may find that you get into a cycle of the relay closing and powering everything up, then the load causes the voltage to drop enough to open the relay again. As soon as the load is removed, the voltage comes back up and the relay closes again.

    I would properly charge the battery, ie over night, connect it to the car and start the engine, and ensure the battery is being charged by the alternator, you should see 14.1v at the battery with the engine running. If so then you want to turn the car off, and stick an ammeter between the battery and live and see if theres a large current draw with the ignition off that would signify a fault somewhere. If there is, you can start pulling fuses to try and isolate the fault.
    #26
  27. voteforpedro
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    voteforpedro Member

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    Well...

    So I got the heater in there and noticed, if I pulled up the carpet slightly by the front passenger seat inner guide rail in the rear footwell, there was a significant amount of water...

    So one thing led to another and I have now pretty much removed the carpet. The foam underneath is soaked. There must be about ten litres of water in the foam alone. The O/S of the car is also wet but not half as much as the N/S. Even towards the front of the car, I can squeeze the foam and it releases a little water. There's some moisture on the chassis around the gearstick too.

    How the **** and why the **** has this happened? Not impressed. The ABS control module beneath the rear bench is wet which might explain the ABS light. It's not soaked, though, so hopefully should dry out.

    I would like to get the whole carpet out but can't. It's joined around the back of the dash. Do I have to remove the entire dashboard and frame to remove the carpet completely? If so, that sucks balls big time.

    In both front corners of the car beneah the dash there's a load of wiring and plugs and things. I see no moisture here, which is good, except it implies the water did not come from the pollen filter/scuttle tray. How can I confirm this?

    If it didn't, then where the hell did it come from? Again, the N/S rear is worst effected but I believe the boot is dry. This means it must have come from the N/S rear door or B pillar.

    Not impressed I have to say. I have never owned a car that can flood so much for no apparent reason. I shall be writing a very angry letter to Audi.
    #27
  28. Turbo Lag FTW
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    Turbo Lag FTW Hate those none insured you know who types

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    I feel for you mate, I had the passenger side of my car flooded but luckily had no electric problems. Guess I got lucky, as for removing the water from carpet and foam I can only suggest a carpet cleaner for removing as much water as possible and leaving the car heaters on full for an hour or two like I had to and as a bit of help use a dehumidifier in the car overnight to remove as much water as possible. I looked to get carpet up and thought it best not too attempt it. Shame Audi missed that design flaw for the drain holes when making the car, leaf`s are the scum of the earth when it comes to the drainage holes.
    #28
  29. aragorn
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    aragorn "Stick a V8 in it!" Staff Member Moderator

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    it will most likely have come from the scuttle, the foam retains the water, wheresas the wires etc under the dash will dry out, the carpet wont.
    #29
  30. Caesium
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    Caesium My BM is fixed!

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    Do you have a sunroof?
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  31. voteforpedro
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    voteforpedro Member

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    Aye, I do indeed.
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  32. aragorn
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    aragorn "Stick a V8 in it!" Staff Member Moderator

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    i guess it could be blocked sunroof drains, but seen as the scuttle was full of water thats where i'd be pointing the finger :p
    #32
  33. voteforpedro
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    voteforpedro Member

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    Well I'm seen a number of hopeful posts on Passat World. Will check the sunroof drains and pollen filter housing today. :)
    #33
  34. voteforpedro
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    voteforpedro Member

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    [​IMG]

    How important is it that these pieces are in place? I remember that the N/S piece, with the drain above the filter housing, was removed for a few weeks while I was messing with my suspension...

    Likely culprit? Even now it's not entirely secure as I broke one of the clips lol

    The guy who provided that image suggests you silicone it down but I wouldn't have thought it would make a difference... the water still runs down into the scuttle, eh?
    #34
  35. voteforpedro
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    voteforpedro Member

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    [​IMG][​IMG]

    [​IMG][​IMG]

    Here is the extend of the damage. I despair. I can't remove the carpet because it joins behind the dash and I am NOT removing the entire dashboard. That pool of water was from one quick squeeze of the foam.

    How on earth am I supposed to dry this out? Tempted to put it on eBay as spares or repair tbh. :(
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  36. voteforpedro
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    voteforpedro Member

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    If there's anybody who lives near Cardiff who wouldn't mind having a look or helping sort this bullshit out, I would be very grateful...
    #36
  37. aragorn
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    aragorn "Stick a V8 in it!" Staff Member Moderator

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    cant you just cut the carpet where it goes behind the dash?

    A wet vac will be able to suck a lot of that moisture out the carpet if you dont want to cut it. Then leave a heater or dehumidifier in the car for a good few hours to dry the rest of it out.

    The little flaps you pointed out dont really need to be sealed down, thats why there is the little drip tray above the pollen filter on the nearside... As long as that drip tray is correctly fitted you wont have a problem with water that gets under the scuttle trim.

    Selling the car is a bit rash! Changing the suspension was a much bigger job than drying some water out, and you managed that! Just get stuck in!
    #37
  38. voteforpedro
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    voteforpedro Member

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    But as you know, the carpet is not what gets wet per se - it's the foam underneath. It would work for the carpet towards the rear of the car but I can't get to the foam towards the front of the car because it's still attached behind the dash.

    I thought about cutting it but can't find a suitable place to cut. It's quite tight behind the dash and I can't get the scissors under it. :(
    #38
  39. aragorn
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    aragorn "Stick a V8 in it!" Staff Member Moderator

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    stanley knife?
    #39
  40. simon1303
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    simon1303 Member

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    when mine was leaking i noticed that the little rain channel that goes across the top of the pollen filter hadnt been fitted properly do all the water was bascially filling up where the fan is and then leaking in to the car that way. put the tray back in and its all fixed now.

    i has a similar amount of water in my car too. borrowed the mother in laws carpet cleaner vacum and sucked it all out of the foam as much as i could. seems to have done the trick so far......
    #40

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