Topic: Gen light
in Forum: C3 Electrical
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C3VR Founder
Eagleville, PA - USA
Joined: 11/1/2001
Posts: 18416
Vette(s): Used to own a 1979 Corvette now owned by JB79
What does it mean if your "Gen" light comes on while driving down the road, especially while stopped at a light? Is the alternator bad? There is a brand new battery in there, so hopefully it isn't that.
-Adam Wartell
NCM Lifetime Member #1222
Founder: C3 Vette Registry
C4 Vette Registry, C6 Vette Registry
My first Vette, now owned by JB79:

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You don't have an alt. guage in the car correct? If not and the light comes on while you are at a stop sign and idling, it means a problem with the alternator. Most likely, it isn't charging the battery and keeping the car running. in short, it means the car is constantly running off of the battery. had the same problem with mine and had the alternator rebuilt and no more problems
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BRADENTON, FL - USA
Joined: 8/4/2002
Posts: 669
Vette(s): 1972 convertible 350 auto trans, delux int, air, ps, pb, t/t wheel, pw, 79,000 org miles Rare one year only color
a simple way to check the alternator is to dissconnect the battery while the car is running. if it,s not charging the engine will stop running. if it's putting out enough power it will keep the engine running. also most auto parts stores will do a free alternator test if you bring it in. they have a setup and hook a belt to it and test its output.
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C3VR Founder
Eagleville, PA - USA
Joined: 11/1/2001
Posts: 18416
Vette(s): Used to own a 1979 Corvette now owned by JB79
Adam said: What does it mean if your "Gen" light comes on while driving down the road, especially while stopped at a light? Is the alternator bad? There is a brand new battery in there, so hopefully it isn't that. |
OK...so I replaced the Alternator.
This morning, while stopped at a light, idling at about 500, the GEN light came on, again! The amp meter was reading about 13.
What is going on!?!?!


-Adam Wartell
NCM Lifetime Member #1222
Founder: C3 Vette Registry
C4 Vette Registry, C6 Vette Registry
My first Vette, now owned by JB79:

Adam do you mean the volt meter ,,, try this connect a volt meter to the battery while the engine is running . The reading should be about 13.8 - 14.2 volts . With the engine at 500 rpm in gear with the heater blower motor running ,,, how do I know that,,, the light will come on . Adjust the idle a bit higher .
gman
let me know if the prob persists
gman
let me know if the prob persists


C3VR Founder
Eagleville, PA - USA
Joined: 11/1/2001
Posts: 18416
Vette(s): Used to own a 1979 Corvette now owned by JB79
4webers said: Adam do you mean the volt meter ,,, try this connect a volt meter to the battery while the engine is running . The reading should be about 13.8 - 14.2 volts . With the engine at 500 rpm in gear with the heater blower motor running ,,, how do I know that,,, the light will come on . Adjust the idle a bit higher . gman let me know if the prob persists ![]() |
You're right... I had the heater blower on! How did you know that?

Now I'm wondering if I replaced the alternator for no reason. Do you think I did?!?
Thanks!
-Adam Wartell
NCM Lifetime Member #1222
Founder: C3 Vette Registry
C4 Vette Registry, C6 Vette Registry
My first Vette, now owned by JB79:

in Forum: C3 Electrical
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