Rallye Engine Battery Light?

[GTI6BOY 29]

Strange problem.......with the car off i have 12 v on the battery,

 

with the car on i have 12 v on the battery,

 

when i rev the throttle the battery light comes on and stays on but i have 14.4v on the battery???

 

any ideas anyone

 

thanks

[M_R_205 5 1 Cars]

I may be wrong so dont take this for gospel, but i thought the alternator should knock out 14ish volts even when at idle?

 

If you look at the alternator there is a smaller wire, that hooks up to the battery warning light switch, give the terminals a clean up see if this fixes it.

[nick9one1 2]

If you look at the alternator it will have two terminals. One larger that goes to the battery and a smaller one which goes to the dash.

 

IIRC when the engine isn't running, the smaller terminal is grounded so the battery light comes on, once the car is running it stops that terminal from being grounded so the light goes off.

 

so maybe disconnect the smaller wire from the alternator and get the multimeter on the terminal. to find out if its being earthed when you rev it.

 

if it is it means the alternator inst generating any current or is faulty. (maybe disconnect the larger terminal and see what its generating from idle)

if not its a wiring/clocks fault

Edited June 1, 2009 by nick9one1