rs_cos

iTrader: (5)

can any1 help me battery light comes on when i start me cossie and have 2 rev it 2 bout 2000 2 get it 2 go out. thanks charlie

Norwegian Wolf

That's because your alternator doesn't give enough current.
It could be the regulator, but it can also be the alternator itself.
You should measure how much voltage it is over the B+ clamp on the alternator to the alternators shell.
On idle, and see if the result changes when you rev it up.
Should be about 14V.
Also measure the battery voltage when the car is running, and what it is with the ignition turned of.

It's probably the regulator, and that is easy to exchange
and cost about 10£.

But first of all get a multimeter and measure the things i have listed above.

Hope this will help you, and hope you understand my poor english

tabetha

The voltage does go up otherwise it would not excite.
Check first the fan belts are not slipping, then clean the "IND" terminal the one with the thin blue wire on it on the rear of the alternator, this needs to be nice and clean as the alternator receives a LIVE through this terminal after it has passed through the warning light bulb first, this live excites the field windings in the alternator so starting production of current.
If not above the diodes are just getting a bit old and lazy, personally so long as the light does go out I would just live with it, but a recon alt would be the best bet otherwise, as only around £35 with 12 months warranty, even DIY regulator/rectifier change will cost you £25 in parts with no warranty!!
tabetha