× Auto Repair Pros Member Benefits TechHelp Knowledge Base Forums Resources My iATN Marketplace Chat Pricing About Us Join Industry Sponsors Video Members Only Repair Shops Auto Pro Careers Auto Pro Reviews
Join Now
International Automotive Technicians Network
05 GMC 6500 7.2 CAT ECM replacement
Posted to HD/Fleet Forum on 12/5/2017 4 Replies

Hi guys, I am having a communication problem on the J1587 serial data bus pins 8&9 at the Cat controller on the side of the engine below the intake, the J1989 communicates fine, I have the .06-1 volt signal but missing the 3-4 volt signal from the controller t... Login to read more.

4 Replies Received (View Replies)