Unexplained Absence

When accelerating at a decent speed my battery and brake light come on. The shut off when I'm maintaining a speed for over 5 mins. Also when I put the key in the ACC position only the temp and the seatbelt lights come on. Almost forgot the Volt gauge in my center console seems to be dropping a couple of notches everytime I turn it on. This all started this afternoon. Could I have blown a fuse or is it just some bad wires? I just installed a new stereo deck into my car but dont think that would be the problem as it has been working without any problems for a few days now. Please help.

Thanks
Ian

audinutt

there is a blue wire that comes from the alternator and runs all the way to your dash. if this wire develops a bad connection or a break the alternator will not start charging.

there is a connector under the hood near the alternator that commonly causes this issue.
another thing you might want to check is the condition of the brushes, the voltage regulator comes out with two flat head screws. i usually keep a spare in the glove compartment, easy thing to grab at your local pick n pull and not too expensive new, some people replace the brushes, but i've had problems trying to get the solder hot enough the allow me to install new brushes.

a whole new regulator should be obtainable for less than $25 and a good thing to look into on a high mileage audi.
on all of the audi's i've owned i've had to actually replace 1 alternator. the rest were fixable with a regulator, one i had to put bearings in also ($10.00).

anyways, if the battery light is not coming on this is showing that the exciter is not getting a power source, hence no charge, you can always determine the pinout in the dash if you have a bentley and use a long jumper wire to test. (what i did on an old 5000 after putting a good alternator on and cussing, still no charge)
ran the jumper wire and volt gauge went to 14v @ idle

HTH!
rich
'86 4kq

Unexplained Absence

and would this also be the reason why only my temp light and seatbelt light come on when i 1st turn the car on? or is it somethin else?

Unexplained Absence

would this also cover why most of the lights in the cluster dont come on(for their bulb check battery, break light, etc...)? and why the battery and brake lights come one under hard acceleration?




Thanks

Ian

audinutt

yankt he alternator and the regulator out and see how much of brush material is left.

HTH!
rich
'86 4kq

Unexplained Absence

I have an 86 4000S canadian version so it has 2.2 L engine. So does this mean I should get a regulator out of a coupe or 4000 q instead of a 4 cyl 4000? or does it matter?

audinutt

but anything with the 5cylinder should definately work, heck and alternator off a 5000 worked on my sis's 4000 4cyl. they are all the same basic assembly so you shouldn't have issues there.

HTH!
Rich
'86 4kq

Unexplained Absence

Thanks for the help Rich I'm going to try it on Monday.