another alternator warning light question
 

i've tried a search but cannot find the same thing. i have no charge, 12.6v on battery terminals running or not, and less when lights switched on. this points to alternator, however, the dash warning does not come on with ignition on but i am getting 12volts at the bulb holder (nothing with ignition off) - how is this possible?!

i have checked the bulb and its fine, and i have also tried other bulbs. is it possible to have 12v and yet not light the bulb? i'm clueless with electrics....

i just want to make sure its the alternator before i order one.

cheers

richard

there should be ground at the blue wire with the engine off...i would check to make sure there isnt a break in that wire....could be a bad connection at the plug in the engine compartment. or it could be the voltage regulator....i believe 86 has a diode also...these can blow out....if it has one it would be right behind the gauge.

thanks, tried it. there is ground when ign on or off. i have 12v so why doesnt the bulb light?!!

did you check the ground before or after the diode? best way to check is remove bulb and holder, put diode on one side of bulb holder . positive on other...then put negative to the opposite end of diode. if bulb doesnt light then the diode is bad.

The Bentley shows the blue wire for the light going through an anti theft unit. Is that still intact?

I'd say ground the blue wire at the alternator and see if it lights but if you've gone that far it is just as easy to replace the alternator


Edit: the wire is blue till it gets to the anti theft unit then it is shown as blue/red

It was the regulator.

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