VW T4 alternator light

Discussion in 'Mech Tech' started by pkrboo, Oct 30, 2011.

  1. My T4 alternator/battery light is on faintly anyone know what the problem could be?

    The battery voltage is 14.7 v but it was a bit low the other day and needed a boost so i think that why it may be a bit high.

    VCDS reads the supply volts as 14.3 v.

    I did burn a wire out the other day (from ignition switch down to fuse box) and have just replaced that
     
  2. Honky

    Honky Administrator

    Did you get this sorted?
     
  3. Could be the regulator in the alternator playing up,i was having the same problem in my T4, i had mine replaced this week for £30 and its fine now
     
  4. Birdy

    Birdy Not Child Friendly

    I'm investigating this same issue with mine. Light faintly on and then gets brighter when you apply the indicators.
     
  5. As it turns out i fixed this just the other day.

    bit of a weird one and i dont fully understand it but i will try to explain.

    1. The Alternator was humming and drawing current with the ignition off so flattening the battery.

    2. The faintly glowing light on the dash did NOT go out when the blue from the Alt was removed (it should as far as I am aware)

    3. Replaced the Alt. and all good but also had to get a new battery as it was knacked from the alt draining it.

    Basically something was broke inside the alt that made it look like it was ok (providing correct charging voltage) but was bringing the dash light on even when the blue wire was disconnected...(which i think is the weird bit)

    Birdy check what voltage you have on the blue wires at the base of your fuse box down near the pedals. if it is anything less than the charging/battery voltage then it is probs the alternator
     
  6. ye my light comes on dimly when the indicators are put on
     
  7. battery light in mine comes on when i press the footbrake whilst driving?
     
  8. Are you sure it's the battery light in the clocks and not the brake light on the dash?
    :)
     
  9. mine does that and always has (ive had it 19 years!)
     
  10. Glowy Alt Light Syndrome is more likely to be caused by the voltage drop in the main feed to the front of the van, rather than anything to do with the charging system. It'll be worse when there's a load on (headlights, flashers), and of course you can't see it during the day. Nowt to worry about, IMHO.
     
    Dicky likes this.
  11. mine does too, an old chap up the road who had bays for years said his always did, I only notice mine when driving with dip beam on at night
     
    Dicky likes this.
  12. I have volt meter on mine on the voltage does indeed dip when dip beam on. and light glows,. cheers.
     
  13. matty

    matty Supporter

    I think its a common issue i have looked at a few turned out to be the engine earth strap
    have ago at cleaning up the main earth points on the body the battery one and the engine one
     
  14. What vehicle are you talking about? A vw t4 or a t2 bay window?
     
  15. Don't expect them to be accurate. I tested three different VDO voltmeters - they all under-read by half a volt, which is crap!
     
  16. Cleaning up the earth strap's always worth doing :thumbsup:
     
  17. no they reckon that, I tried alsorts, even ran a new feed to the front . but now it's a quirky of the bus, we just laugh and point at it, .......that's why it probably does it.:rolleyes:
     
    snotty likes this.
  18. I wouldn't worry about it - 'tis just a quirk. Having a small lightbulb hanging on the end of 20 feet of cable isn't a brilliant design idea...
     
  19. Birdy

    Birdy Not Child Friendly

    I had 2 Citroën Visa's that did it with no problems. My response now is "They all do that" :lol:
     
  20. Zed

    Zed Gradually getting grumpier

    My westy did it for 10 years. :thumbsup:
     

Share This Page