It all started the other day when I noticed my battery light started flickering on and off. after a while it just stayed on permanently.
It started fine for the rest of the day althought the battery light stayed on.
The next day I tried to start it but my battery was dead. I got my jump leads out and got a jump start to work.
Just as i got to work the car completly cut out.
I presumed my alternator was not charging the battery up so as soon as I got towed home I went out and purchased a working one, after an hour of hard labour I had fitted the new one. I tried my half charged battery and it started up, but the battery light never went out.
after a small drive round the block my lights started fading and my car began to cut out.
Any sensible clue to this would be much appreciated as I was sure it was the alternator.
Its a 1996 P reg Punto s60 1.2

Are all the connections(inc earth)clean & tight at alternator & from there to battery.Belt ok?

dam i was sure also. unless there is an inernal fault with you battery and its not holding a charge, you have a different battery you can try for experiment?


isit one of thembats you supposed to keep eye on levels and top up

Its a delphi standard Maintanence free, I have got it on charge now. I will have to get a new battery to try. Im pretty sure all the connections are fine on the new alternator, only thing I can think trying is checking to see if the battery light goes off when I get a bump off my sisters car, would this prove its my battery at fault and not my alternator ?

Should I have given my battery a full charge before I tried it with the new alternator ? But then it wouldnt of killed it after me driving round the block...
I will update 2moro on the probs........

Battery light wont go out if the battery is good, only if the system is charging. To charge the battery the alternator has to have a live "exciter" wire. This is basically a live supply that goes through the bulb and connects to the alternator. When you switch ign on the wire goes to earth internally through the alternator and the warning light comes on.

When started and charging occurs the exciter wire is "self sufficient" and the alternator puts voltage back up the line to the bulb, because there is no earth the lamp goes out.

Therefore, if you have a warning light staying on AND the battery is not being charged, it is highly likely that EITHER the alternator is faulty OR the wiring is shorting out to earth before it gets to the alternator.

Check the exciter wire for voltage with ign on and charging, ign you should have 0 volts as the alternator is providing the earth, when engine running you should have 12 to 14 volts. If results are any different then remove exciter wire and check feed with ign on, disconnected the voltage should be 12 volts and warning light should be off, if voltage is any different or lamp stays on that proves your short circuit to earth.

So u dont think I have a problem with my battery then ? Hmm someone was saying something about diffrences in the 8V and 16v alternators could this be my prob, I just went to a breakers yard and got a 1996 punto alternator regardless of 16V or 8V

Turns out there is some sort of problem in the wire, I took the wire off and scrubbed the ends with a wire brush, this has sortov solved the problem but I still got a flash of the battery light while I was driving, it must be shorting out somewhere but I dont know where or why.........

How can I stop the wiring shorting out to earth ?

you are going to have to find out where this is happening make. look for any wiresthat run close to chasis and make sur they insulated and not worn anywere.