Express 4500 V8-6.0L (2010)
every module that could be optioned into the vehicle. If an option is not installed on the vehicle, the scan tool will display No Comm for that options
specific control module. In order to avert misdiagnoses of No Communication with a specific module, refer to Data Link References (See: Testing and
Inspection/Initial Inspection and Diagnostic Overview) for a list of modules, the bus they communicate with, and the RPO codes for a specific module.
