Battery light always on??? - Ford Forums - Mustang Forum, Ford Trucks, Ford Focus and Ford Cars

Maroon Falcoon · 10-06-2004, 21:59

My Battery light is always on when i am at idle but when revs increase the light turns off, it totally turns off at aorund 3800rpm.

All wiring is fine, could it be alternator or rugulator, or the brushes inside the alternator.

And would a EA alternator work in my XF, it is a carbi.

Klawsterfobik · 10-07-2004, 03:07

My alternator light stays on til i give it a rev over about 1200rpm. Then it goes out. I figure its the the alternator not having enough revs to produce power. So your taking out more power than what your putting in. If you can, test it by starting it and seeing what power you've got in your battery when its idiling (when the batt. light is on), and then take the revs up to where the light comes off and check the voltage in the battery. Should be about 14.??.

I doubt the EA alternator will fit mate.

Aussiblue · 10-07-2004, 05:28

Usually means you need a new regulator.

Maroon Falcoon · 10-07-2004, 23:55

When at idle the voltage was around 12.2 and then when i revved it until the battery light had turned off it was still the same.
Any ideas on what this could be exactly,
Cheers.

Klawsterfobik · 10-08-2004, 00:35

Even when you held it at the revs where the battery light went off the volts were 12.2? Id say a new regulator too..

Maroon Falcoon · 10-08-2004, 04:02

yes at all rev ranges it was around the 12.2 volt mark.
Looks like ill be going and getting myself a alternator this weekend, thanks for the help anyways

Freak · 10-13-2004, 17:33

If you havn't bought a new alternator already, regulator's are only around $10, so it's worth a try anyway.

Maroon Falcoon · 10-13-2004, 23:08

Yeah i got an alternotor second hand for $20, had a new regulator on it anyway coz i changed some parts over because the bearings were making a loud noise. Now its all good and clean with no problems, and people were trying to charge me about $25 and $40 for a reg so yeah...