I have a 2007 Envoy 4.2, For the past two days my battery voltage was 15.2 I took the car to the shop and they said it was a bad voltage regulator but it would be better to just change the alternator because it was inside that,ok they did the work. when I got into the truck to leave i was again getting a reading of 15.2 they said don't worry as long as it does not go above that. I made a couple of stops on my way home and noticed that after I start the truck up the reading is 15,2 but within 3 min of running the voltage drops to around 14.1 everytime i restart the engine this happens. Is this normal
Alternator Problem
- Thread starter steve620
- Start date
Molson02536
New member
That's normal when your battery is getting old and you may need to new battery. Have your battery load tested and see if its still good or may need to be replaced soon.
When your first start your Envoy, if the battery is not fully charge. The alternator will raise the output to charge the battery as quick as it can and when the voltage to your battery has reached 12 volts again, your charging will drop back to 13.5 volts.
Take not also that if your using the volt meter on your dash, the stepper motor could be off and be giving you a false reading so best to use a multi meter and get a correct reading from your battery post to see if your alternator is charging at 15.5 or 14.5 or at 13.5 where it should be with a good battery.
keep us posted and stay safe
Molson02536
