Voltmeter in the instrument cluster.

[bigT63]

I'm that person that always checks the gauge cluster while driving. I have noticed the voltmeter fluctuates from 12 to 14 often. Every late model Chevy I've owned and used as a company vehicle have always sat at 14 volts while running. I called the dealership and the service tech said there is a new module in the new models, it's called a 'generator control module'. It's designed to periodically charge the battery when needed instead of constantly. This is supposed to help with fuel economy.

Anyone else notice this? Is this module even a thing?

(P.S. this happened on my '17 2500. My '16 Tahoe hasn't experienced this but has the same module.)

 

[greenhornet]

I'm that person that always checks the gauge cluster while driving. I have noticed the voltmeter fluctuates from 12 to 14 often. Every late model Chevy I've owned and used as a company vehicle have always sat at 14 volts while running. I called the dealership and the service tech said there is a new module in the new models, it's called a 'generator control module'. It's designed to periodically charge the battery when needed instead of constantly. This is supposed to help with fuel economy.

Anyone else notice this? Is this module even a thing?

(P.S. this happened on my '17 2500. My '16 Tahoe hasn't experienced this but has the same module.)

Yes it is in all the newer models . There is no point in charging flat out if it does not need all that is available.

 

[Kittmaster]

Yeah when I first got mine, it freaked me out.....the dealer (manager and good friend) told me what it was doing and that unless a "message" to service the charging system, then it is operating normally. I guess it serves as less parasitic drag on the belt line as the magnetics are disabled somehow to create less drag.....

 

[dubyagee01]

My 05 has this. Ive read that unplugging the inductive current sensor on the battery cable lets it charge like normal. Mine is still connected.

 

[dbbd1]

My 05 has this. Ive read that unplugging the inductive current sensor on the battery cable lets it charge like normal. Mine is still connected.

I wonder if that would throw a code though...

 

[dubyagee01]

Ive read theres no code. I like this option though. Unless the AC is on max. Then it slows and speeds up. Also at prolonged stops it will bump up the idle in gear when voltage drops too low.