C4Battery Light
Thread Starter
Instructor
Joined: Apr 2003
Posts: 148
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From: Lakwood N.J.
C4Battery Light
The battery light came on in my 89 vette. Does it mean the battery is bad or the alternator is not charging? If its the alternator what wires do you use to check the output. Thanks in advance.
Race Director
Joined: Apr 2002
Posts: 10,036
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From: Anaheim CA
The battery light comes on if the voltage is below 11.5 volts. Usually that means the alternator is bad.
You can test by turning on the ignition without starting the engine. Note the battery voltage. Start the engine. What you now see is the alternator voltage (assuming it's working). It should be about 13 to 14.5 volts.
You can test by turning on the ignition without starting the engine. Note the battery voltage. Start the engine. What you now see is the alternator voltage (assuming it's working). It should be about 13 to 14.5 volts.
