The Cummins R.28 CM2220 engine package provides J1939 communication over CAN bus which is compatible with the COMPUSHIFT controllers. Wiring to the CAN bus can be difficult because Cummins hasn't provided a connector for it.
The standard CAN bus connectivity kit HGM provides for the CS3 has a CAN bus T and terminator at the end. The Cummins loom has two termination resistors provided already, one at the engine side in the engine compartment, and one at the gauge side, in the vehicle. HGM recommends removing one of these resistors and connecting the provided HGM twisted pair leads there using solder or crimp splices.
6. Terminating Resistor
Making The Connection
Cut the terminating resistor from one end of the Cummins loom. Connect the HGM provided harness as follows in place of the resistor.
Cummins ECU Pin
COMPUSHIFT Controller Parameter Settings
Vehicle Settings > Engine Type
J1939 High Speed Diesel
Network Settings > CAN Bus 1 Baud Rate
You can diagnose CAN bus problems by going to Diagnostics / Network Diagnostics on the CS Setup App.
CAN 1 Receive Count should be steadily increasing when the ECU’s are communicating correctly.
The error counts should always be 0.