I have a 2006 silverado 4WD with 95,000 miles on it. I noticed my battery light was on and the dash voltage gauge was down around 10-11 volts. I tested the battery and the alternator with a multimeter and both were reading 14 volts. I took the truck in to the shop and they said when the alternator is older it will stop sending a good signal to the dash gauge. They changed the alternator and the problem was fixed for about a week but began to have the same issues today as before. The alternator is AGAIN putting out 14 volts and the battery is at 14 volts as well. The dash gauge is down around 10-11 volts with the battery light on. any advice on what could be causing this?
Thanks,
James

What are you getting for a voltage reading out of pin 16 of the DLC?

With a scan tool, they should have taken readings of the Generator Battery Control Module....