Battery warning light stays on?

["james_hartshorn_uk" <james.hartshorn@xxxx>]

Took the "D" out yesterday on along run, parked up for abit, started 
the beast up and the battery warning light wouldn't go out, now the 
volt display is reading a charge (tried it today needle sits around 
the 12 volt mark) , as I rev the engine the needle increases, put all 
the lights on, the needle decreases alittle, rev the engine the 
needle increases again, but the little red warning light still 
remains on, any ideas anyone...

(tried it today, the needle sits around the 12 volt mark, but driving 
home in the dark last night all lights on the needle sat on the 2nd 
volt mark between the 8 and 13 is this correct?)

Also the battery was fully charged last week.

James Hartshorn Vin #569