Battery light not going out.

[krzracingcouk]

Originally Posted by msh

what's the reading of both?

When doing the last test the VDO read about 11.5v and the meter was 15.2v - I know when the battery light goes out the VDO normally goes up to about 13v

Originally Posted by msh

If you can remove exciter wire from alternator, and alternator light keeps shining, apparently exciter wire is grounded somewhere - but alternator self-excites if it's being revved behind some threshold; let's say, if engine is revved past 3k rpm - just for your info, if you continue to drive the car without this problem being solved.

That was what I had to do on the old alternator, but had to hold rpm above about 4k and sometimes red line it after driving for about 3 to 4 minutes - used to get funny looks driving along doing that.

Originally Posted by msh

As for "electronic trickery" John is speaking about - in order to rule that out, you can remove oil pressure warning relay - in VW's it's in cluster itself, but in audis of this age it's separate relay, must be above drivers feet [at least in LHD cars], with "õl druck kontrolgerāt" written on it, if you remove it, that removes oil pressure warning [both buzzer and light], but if that restores normal behavior of battery light, you'rs is faulty.

I have a relay behind the dash and always wondered what what was for, I do not have a buzzer as far as I know but do have the oil light flash while the battery light is on. I will also check that.