I have a 07 silverado classic Z71. The voltage on the gauge while driving alternates between about 11 to 16 volts and the lights and hvac blower motor go up and down with voltage. I have for a long time been convinced that the voltage regulator is going kaput. Is there a bulletin or recall for this on this vehicle?

I started to take off and have rebuilt the alt. During the process I noticed something new on me. There is a module on the battery cable and it has way looks like an Inductive amp clamp. What is this and what does it do? Could this have any thing to do with my issue?

I am sorry I did not realize that I was posting in uplander thread. I found this by search

 

Moved as requested.

 

Chances are its the alternator GM products have built in voltage regulators. But before you replace it check all of your connections, a loose one will cause this...Battery Alt. Starter an so forth. Also a loose connection will "burn out " your alt. over time.

 

What is the module for and what does it do

 

picture please

 

It has what looks like a GM part number of 15857953

Any one know how to post pic with iPhone (not with URL). Our computer is down