(G) No Battery Light, car does not charge!

Hi, I'm having trouble with the girlfriends N reg 1.0E Start Fiat Uno!

Bassically for the last month or so the battery light would come on randomly, but the car would still run fine and kept the battery fully charged.

Last week whilst I borrowed the car it died onto way to work, turned out the battery was flat so I bought a new one on my lunch break and drove it home later ofter work on the new battery. When home I then tested the voltage and noticed that the alternator was not charging at all, on closer inspection i noticed that the battery light was not illuminating at all on ignition - basically it never comes on at all - even when it's supposed to just before you start the car!

Over the weekend I've tried 2 second hand alternators from the local scrappy, niether of them fixed the problem and the battery light stays dead on both - I've checked battery connections to the alternator and they're fine, earth is also fine and i've removed the dash and checked the bulb and that's all ok. I've also checked the schematics out and noticed that the bulb connects directly to the d+ out of the alternator so i've also tried conecting a fresh wire from the alternator to the bulb and still no joy.

I've got another alternator here with me now that I had delivered to work which i'll try out later tonight, but i have a horible fealing it's something else! Anyone else here have an idea that could help and would a dodgy alternator stop the battery light from coming on at all??

To be fair the two alternators I've tried so-far have looked dodgy and the second one made a horible noise when fitted so I'm pretty sure that one was duff anyway so here's hoping!!

Cheers!

Check the bulb in the dashboar there are some vehicles where the battery light is part of the circuit and if the bulb is blown it wont complete the circuit its worth a try instead of changing alternators all the time, that and also check all your fuses.

Checked the bulb and fuses already - I've also wired up a fresh wire from the bulb to the alternator and still no joy. The only part of that circuit that I have not tested is the from the bulb onwards! No idea where it goes from there...

how about testing the alternator with a multimeter?

Might sound obvious, but did you make sure all the connectors were put back onto the alternator when you changed it? Are the connectors ok? (i.e. not corroded, which might have caused the original problem.)

Also as Bandido suggested, check the alternator when it's running with a multimeter. Simply check for volts and amps across the battery and you'll see whether it's charging or not.

Good luck!

All sorted now! Just fitted the 3rd Alternator and all works well! Just unlucky with the first 2 I guess....

The symptoms are those of worn carbon brushes inside the alternator(s).
0,8 EUR/pair, 5 minutes soldering job.