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Alternator Not Charging 2002 TB

MA Trailblazer

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MA Trailblazer Enthusiast

MA Trailblazer

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Posted

When it is very cold out, ( below 25 ) my alternator will not put out a charge for the first 10 seconds. You can see the volt gauge shows a discharge for the first 10 seconds, and them it jumps up above 14 volts after the first 10 seconds. This will only happen it the very cold, and only if the motor is cold.

 

WHen it is dark out, it is very noticable because the headlights will be dim for the first 10 seconds, the when the volts gauge jumps up, the lights get very bright.

 

Anyone else notice this, or is there something wrong with my alternator?

 

2002 Trailblazer LTZ.

 

John

MA Trailblazer Enthusiast

MA Trailblazer

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  • Author
Posted

It turns over fine and starts fine, but the volt meter gauge will show a BIG discharge, and the lights will be dim until the alternator puts out some power after about 10 seconds.

 

John

TO2FST Enthusiast

TO2FST

Posted
Posted

hmm then I dunno, I was having problems with the truck not starting at all in cold weather, had to have the BCM Module replaced, and all my settings including ONStar reprogrammed

 

-Frank

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