if i unplug the alternator plug shouldn't the idiot light come on?

[bpman1234]

like the post asked thanks in advance.

 

[Turbo6inKY]

Nope. The idiot light wire is rigged to the regulator in a way that grounds it if the regulator fails.

 

[bpman1234]

thanks for the quick reply trying to figure something out I got 2 alternator acting the same way there both just giving me 12.5 volts.one I rebuild and 1 I got from pepboys.

 

[Turbo6inKY]

I always have the parts store test an alternator I'm buying before I leave the store. They have about a 50% failure rate out of the box.

 

[bpman1234]

yea I called them in advance to get it in for exchange so will have them test thanks got one question would not soldering the regulator in place when rebuilding make the alternator do that .worked for about a month after I put it together all newparts.then got the one from pepboys it did the same thing any idea's?

 

[pacecarta]

with key on engine not running the volt idiot lamp should be on, if its not odds are your charge circuit is incomplete and the alternator is not exited so it has no output unless your dash lamp socket has the resistor on back of that lamp (provided the contacts to the back are good and its just a bad bulb )
caspers field fix would help if no lamp

 

[bpman1234]

yes it has the resistor in it but will check to make sure it's turning on.

 

[bpman1234]

nope not volt light when I turn key on engine not running.

 

[pacecarta]

the resistor wont help if the socket doesnt make good contact with circuit film so seeing bulb lit is an indicator that socket connection is good

you could temporarily wire a bulb in at rear of alt from field connector to bat post ..if no charge ..alt is bad

 

[bpman1234]

gonna take it apart as we speak.see what'' up.

 

[bpman1234]

took it all down took out the plug that holds the bulb cleaned all contact I've even the one that plugs to the ribbin circuit. bent them a little too to make better contact still it doesn't turn on .

 

[pacecarta]

is alternator installed and field plug plugged in ? wont light if its not

 

[bpman1234]

got it replaced the resistor bulb and all is good. wow now the water temp lights up too.thanks guys .love you guys.lol

 

[earlbrown]

I still wish I could have dinner with the genius that invented that field circuit for GM alternators.


So I could shoot him in the face.


That's the only warning circuit that I've ever heard of that will take out what it's monitoring when it fails. It'd be like a bad fuel gauge knocking a hole in the gas tank if it flakes out. Or if the oil light fails and turns off the oil pump while running.