Battery warning light... Not lighting, consistently.

[Reimotim]

Ok so my battery warning light used to illuminate when I turned on the ignition and then go out when the engine had started. It worked effectively when my alternator belt snapped a few months ago.

BUT...

Now it doesn't illuminate when I turn on the ignition, although occasionally it will light up if I let the engine idle for a long time (so I know the LED is still functioning).

Is this just a poor earth connection?

Cheers
Tim

[Hacksawbob]

Yes probably earth, check alternator to engine and engine block to battery, esp gearbox nose mount.

[Reimotim]

Cheers Bob!

[Hacksawbob]

of course check alternator out put is sufficient first!

[Reimotim]

Not great with understanding electricity, but surely if the output of the alternator wasn't sufficient then the warning light would be on?

[Oldiebut goodie]

The bulb comes on when there is an earth route via the alternator when the alternator is not turning. When the alternator is running the earth is negated by the alternator output. If the light comes on /flickers whilst the alternator is turning there is a problem with the earthing or alternator output, usually the earthing everywhere could do with renewing/overhaul.

[colinthefox]

.................or the regulator brush pack might be worn out. Interference on the radio at high revs is sometimes a symptom.