Battery light on, 14.4V at the battery!

**Saulty** · 16th January 2011, 22:49

I have a 2005 facelift 1.8 Vectra. Last November the battery light came on and on testing the voltage at the battery I had about 12v. Obviously not charging so ordered a new alternator which was fitted a couple of weeks ago. The battery light fault was intermittent and if it came on while driving I would go into the hidden menu and read the voltage on the display which would also read about 12v. When the light went out it would read about 13.7v.
With the new alternator it was charging at 14.4v. Last night the light came on again but the display showed 14.4v. When I got home a put the voltmeter on the battery which also read 14.4v but the light was still on!
This morning the light is out and battery is charging at 14.4v.
Can anyone shed any light on this?
Cheers. Matt.

**macdad** · 16th January 2011, 23:09

?Did you get a brand new alternator or a recon one,i once had a similar fault as yours and it turned out to be the voltage regulator,needs bench checking by a Auto spark if you have one near where you are,

**Saulty** · 16th January 2011, 23:12

Alternator was brand new! I'll see if I can findan auto spark to test it, if not might see if I can get it replaced under warranty!

**DHobbs** · 16th January 2011, 23:29

Is the battery OK? If it's not holding it's charge, that may cause the light to come on.
From personal experience, replacing the alternator is usually followed by replacing the battery.
Worth testing anyway.