I have a 2003 GMC K2500 4X4 with a 6.6 diesel . The ALT went bad and the volt gauge went down and the picture of the battery above the volt gauge went on. I replaced the alt ,the battery is charging and the volt gauge reads 14.8 volts but the picture of the battery is still lit. I scanned the truck and it has a P code P0621,I checked out Aldata and there is no listing for that P code. Is there a reset or what should I do to shut off the picture of the battery light.
Thanks Keith
Thanks Keith