Ccmnova

2008 4.3 liter V6. Battery light coming on and service charging system note on dash. Battery and alternator check out ok so I’m guessing it may be the voltage sensor ?? Can anyone tell me (pic) where it is located - thanks

mountainmanjoe

it's part of the computer, and it's unlikely to be bad. What's your system voltage with the engine running?

Ccmnova

14.6 volts running. 12.6 not running. I was told the voltage sensor is near the battery ?

mountainmanjoe

Some vehicles have a current sensor clamped to the negative battery cable, but it's completely solid state. There's nothing to really break on it, unless the plug is loose or corroded.

I think you should run a full diagnostic scan with a high end tool to see if there's any stored faults that will narrow down the problem for you.

Ccmnova

In checking online, it’s noted that the voltage sensor is known to fail and will cause the battery light to illuminate and pull up the “service charging system” note on the dash. Anyway, I’ll try to locate it on the negative battery cable.

mountainmanjoe

noted where? I've never heard of a failing voltage sensor.
The thing on the battery cable is a CURRENT sensor. voltage is not current.

Check to make sure all battery, alternator and ground connections are clean and tight.
You can have your battery + alternator load tested for free at most parts stores.

Ccmnova

What are the symptoms of a bad battery voltage sensor?
Warning Light: When the Battery Current Sensor malfunctions, it often triggers warning lights on your vehicle's dashboard. These lights can include the Battery Warning Light or the Malfunction Indicator Lamp (MIL). The Battery Warning Light typically resembles a battery and signals a problem with the charging system.Dec 29, 2023

mountainmanjoe

You're putting the cart before horse. When you come to a doctor, he does tests to get more information. He doesn't assume the most unlikely scenario and go "right lets cut out your prostate and see if it was cancer. Oops it wasn't ... lets try something else." and then it turns out you're just constipated. You need to measure, test, diagnose, and proceed according to symptoms and results. There are many causes for the warning light, so start with a diagnostic and load test. 👍

here's the professional diagnostic procedure:

https://charm.li/Chevy%20Truck/2008/...System%20Test/

Ccmnova

Battery and Alternator check out good. No corrosion anywhere I can see.
During idle, the belt tensioner was jumping around a little so I replaced the belt, tensioner and idler pulley.
Anyway still getting battery light - that's why I wanted to replace the voltage/current sensor which can also cause some issues.

mountainmanjoe

waiting for those diagnostic results. bad sensor will certainly trip a B1516 DTC or similar.