PDA

View Full Version : Battery light staying on - how to test alternator???



alex_e3
09-06-2007, 17:26
Jesus, one thing after another! Damn french cars!

As above, the battery light came on in he clio yesterday. Alterator belt is still on & p/s is ok.

I've got a multimeter here, i'm basically wondering how do i go about testing the battery and the alternator??? & what readings should i be getting?

Thanks,

Al

AmDaMan
09-06-2007, 17:30
with the car running put your multimeter on the + and - of the battery and tell us what the voltage is. should be around 14v.

Check all your connections to the alternator are ok too.

Jamie.
09-06-2007, 17:40
As above. Mine came on and then off - finally stayed on. Prob will be the alternator if its not have probs starting.

alex_e3
10-06-2007, 10:50
with the car running put your multimeter on the + and - of the battery and tell us what the voltage is. should be around 14v.

Check all your connections to the alternator are ok too.



Cheers fella. That's how to test the battery iirc? I've seen an autoelecy test an alternator before, but i don't know which connections they put the meter on, or what readings to look for?

AmDaMan
10-06-2007, 11:28
You can test the batt that way, by not having the engine running. It should read around 12v.

With the engine running though it should rear around 14v, this tells you the alt is charging the battery.

richy
10-06-2007, 13:02
if you want to test directly off the alternator then u need to put your positive lead from the multimeter onto the live wire, its the one with a 13mm nut - thick wire on the back of the alternator, then put the negative onto battery negative , with the vehilce running you should see about 13.2v-14.4v

but as amdaman says its easier put it across the battery terminals to see what its reading!

alex_e3
10-06-2007, 14:45
Cheers for that info guys!

However, after i posted, i just went down to my workshop and changed the alternator!

It was the problem, the old was was making a right noise when i spun it by hand.



Surprisingly, for a french car, it was an easy job! Well, apart from single handedly taking the bonnet off!

richy
10-06-2007, 17:24
lol, at least thats fixed! :)

alex_e3
10-06-2007, 22:04
Aye, i'm sure there'll be something else before i get round to droppin the willy engine in!