Intermittent battery warning light

[Thecko]

Does anyone know what might be going on here? Got back from Holiday last night and after driving a little while, mostly once I'm up to speed on faster A roads and carriageways, the battery warning light keeps coming on and going off (accompanied by the rather loud beep when it comes on), sometimes comes on and goes off again immediately, other times it comes on for a minute or two before clearing.

There is no problem with the belt to drive the alternator, it's not loose.

I've put a multi meter across the battery terminals and with the engine not running the battery is kicking out 12.3 volts. With the alternator running this goes up to 13.3 volts.

Any ideas?

[KenONeill]

Intermittently sticky sprague clutch in the alternator drive pulley; try tapping the pulley nose with a mallet.

[softscoop]

Also check the the leads are properly connected to the battery

[Thecko]

Intermittently sticky sprague clutch in the alternator drive pulley; try tapping the pulley nose with a mallet.

Thanks I'll try that - I do like percussive maintenance solutions If all else fails, hit it with a hammer!

[Rob.]

Did you get anywhere with this? Mines developed the same habit today.... Gonna check the connections to the batt tomorrow as the garage put a newen' on last week..