trucks broke/Fstop help!!!

[f5fstop]

Originally Posted by usetosellhummer

Sounds like the tech needs to just clear the codes and do the bulb on the tail. Gm products use two way wireing where the system can cahnnel many diffrent functions through less wire. i have see H2's trip diffrent codes or even check engine for stupid stuff. And never let anyone mess with the Onstar or Cut the radio out. They got to know their stuff. Chip is correct

Two-way wiring is called the class 2 serial data bus.