popdemonic

I have fixed my Alternator problem last night.
I've got 120A Alternator from my friend.
After Replaced it Seem I didn't help.The car
was still running with the Battery not the Alternator.The Battery light on the Autocheck.
So I checked the voltage on the Alternator
it's ~13V checked on the Batt. it's ~12V.
It's sound ok. but It weired that why the volt meter on the IC was keep dropping til 8.5V.Finally,I decided to switched the engine off to protect unexpected situation from insufficient Voltage.Finally,I jacked up the car and checked the connector on the Starter and found that the nut lock was loosen.The connector was short the circuit bewteen the wires that running to the batt and from the Alternator.I removed the connecters and brushed
with the sandpaper.Put everythings on,the cranking is very quick and powerful.the Volt
meter on the IC shown almost 14V w/o load.and slightly drop to 12.5-13V with loads(A/C,Radio,Lights).Here's my good news.

quattro.pilot

Alternators always put out a higher voltage (~14v) than what the battery (12v) is because you must input a higher voltage in order to charge the battery.

popdemonic

Anyway,IMO with running the voltage shouldn't be over 14V(controlled by VR).I've seen HUCO regulatated @14.5V.Too much overcharged shorten battery cell.I also tested the function by rev the engine up to 2-4K the voltage is constant.with the engine off the volt meter on IC shown 11.5-11.8V(previously,i've got 9-10V before cranking.)the starter sound was damn weak.

20VT90q

I can't see that hurting the battery. For those with the Optima lead acid batteries (me), it's definately a positive.

popdemonic

I have been experienced the overcharged alternator @ 19V.finally,it blown the battery
:-(.

Thefeek

I keep reviewing this thread hoping to get more out of it, but I think it's time to resurrect it to ask for some feedback.

I have a '92 S4 that I recently purchased. I replaced the battery and after checking the alternator replaced that too. (120amp Bosch Reman with 14V reg) When I installed the new alternator I fired up the motor and checked its voltage output before buttoning up the front end and got 14V. Check. Once all was together I started the engine and checked the battery at 13V, and the jump starting stud in engine bay at 13V. I checked all wire mounting connections except for the one somewhere in the interior area where the main battery and jump start stud tie in together. Just haven't found it yet.

I drove it around for a couple days then last night after replacing the seat heater switch lights I ran another cursory test with engine running: Jump starting stud at 12.75V and alternator at 12.79V.

Since the car has no voltage meter in the IC and I get no red warning light, is this ok? It seems low to me but I'm new to the Audi experience. Is it normal for these cars to run at just 12.5 to 13V? Could any of you do a quick test of your cars and share the data? I've found the voltage between the battery and jump starting stud to be the same so I've omitted pulling the back seat up lately. Thanks for reading this and thinking about it.

CoryC4

Theres seat heater lights? WHAT! I think every light on the inside of mine is broken

Thefeek

Yep. They're on when ever the key is on. You can pop them out and unsolder the bulbs and replace with LED's. There's a DIY on this URL http://www.elektro.com/~audi/seatheater/fred/

GoHeels

...wait. My seat heater lights are only on when I roll the switch to 1-6. They are not on when they are in the "off" position.

The light is in the dial-switch, by the way, and shows what #(1-6) the heat is on.

Thefeek

The little seat icon above the wheel is lit whenever the key is on. It's the same bulb that has its light blocked from the wheel at zero but open from 1 to 6.