S4_Cinci (I S'edTFA)

I have a situation on a non-Audi that the low charge warning light has occasionally illuminated on the dash (no gauge). The battery measures 12.2 Volts with engine off and 13.1 Volts with engine on and alternator running. I have cleaned all cable and ground connections and the belt is not slipping. The alternator shaft is spinning freely. My diagnosis is that the voltage regulator and/or alternator is dying and while the battery is still realtively strong, it will eventually not be charged fully. I am pretty sure that a healthy unit should put out 14 - 15 Volts.

Does this sound correct? My previous experience has always been total death of these components and I have never caught one on its last legs before. Don't want to overlook something else that would be less $ than a new alternator (getting just a new regulator is not economically feasible compared to a rebuilt unit and would be a special order item, rebuilt unit is readily available). BTW, the one on the car is OEM and has 182k miles on it...(yeah, I think I got my $'s worth out of it!).

Thanks a lot for any help you can provide!

Nick Gustas

less magnetic flux, less output power.

Mine were toast at 120k something, brushes just wore out and ran out of travel.

S4_Cinci (I S'edTFA)

to the regulator on this alternator (FoMoCo). I'm 99% sure I need a new (rebuilt) one, just wanted some outside reassurance. Thanks!!!

reefer_bob

You should be able to go down there and have them put the alternator under a load for testing.