Here recently my battery light comes one...the red one on the speedo...but not the message window...it happens sometimes when accelerating at high speeds and under load....I looks as if the alternator stops working.....but then agin it looks like it works fine and the battery light goes away. I took it to advance for them to run the alternator/battery machine and the machine would not pick up the alternator. the guy there says that usualy happens when there is a bad ground on the alternator.

Where the best place to look for a bad ground?

Thanks
JON

 

Or a slipping belt...

Look at the battery itself for corroded terminals and cables. On the back of the alternator, you can check the cables for tightness. Alternator replacement on higher-mileage A4s is certainly not unheard of.

 

There are plenty of ways to test an alternator, if you don't have a multimeter you can always take the alternator into a pep boys or an autozone to have it tested on thier little tester tool thingy.

 

I know it's not a slipping belt...when she was trying to test it I was looking at the alternator spinning ...and she said there wasn't one being picked up (when the light was on)....when the light was off....when I checked it like a week earlier because it flashed...she said everything was fine even under load....

The wires on the back of the alternator do they just plug in...I haven't gotten a chance to monkey with it to much...are there any cables that ground out to the body or anything like that.???

 

there should be a wire on the back of the alternator that is held on by a little bolt then it grounds to either the engine or chasis. check those 2 points and check your battery like tweaked said. as a matter of fact, check all the wires on the alternator lol

 

So as an update...fo those searching this later...I tried to replace the alternator but I couldn't get the fan off to remove the lower alternator bolt...tried to take it into the dealer and they are backed up for 2-3 weeks...so I'm going to try one more time....

There are two allen bolts the hold the alternator on the obvious one thats high and one that is low that is like 8mm I think.

To take the fan off you need to jam the pulley with something through a hole on the pulley aginst the block you'll see the convient place to jam it at from the top view. the bolt comes off clockwise that rest in between the fan/pulley. The fan has to be removed to gain acess to the lower bolt.

I just can't get the fan off.

JON

 

When the dash light appears, does the voltmeter read 14V?

 

No when the light is on...it's reading 12 or a little less on the dash voltmeter...

Update:

I've tried to get this fan off but I can't seem to get the right tool what did others use to get this thing off...???


JON

 

You can get it out without putting your car into audi field service mode ( taking the front bumper off).... But, it will be tricky. Mechanics have all different anglers for their air ratchet. Can you get channel locks or a small pair of robo grips on the outside?

 

Anyone know what size this but is???? Is it a 36mm???? Thats the biggest "special wrench" that I can find searching for special audi tools...

JON