For a complete wiring diagram Refer to Section 8W.Possible CausesENGINE CONTROL MODULE POWER AND GROUND(D65) CAN C BUS (+) CIRCUIT OPEN(D64) CAN C BUS (-) CIRCUIT OPENENGINE CONTROL MODULE1. TEST FOR INTERMITTENT CONDITIONTurn the ignition on.Ensure the IOD fuse is installed and battery voltage is between 10.0 and 16.0 volts.With the scan tool, select ECU View.A red X will be next to the module that is not communicating, indicating that the module is not active on the Bus network. A green check indicates that the module is active on the Bus network.Check the TIPM for any active CAN C hardware and any ignition related DTCs, perform DTCs before proceeding.Does the scan tool display a red X next to the module?YesGo To 2 NoThe no response condition is not present at this time. Using the wiring diagram/schematic as a guide, inspect the wiring for chafed, pierced, pinched, and partially broken wires and the wiring harness connectors for broken, bent, pushed out, and corroded terminals.2. CHECK ECM POWER AND GROUNDCheck the ECM power and ground circuits. Refer to 9 - ENGINE ELECTRICAL DIAGNOSTICS - DIESEL for the diagnostic test procedure.Were any problems found?YesRepair as necessary.Perform the ECM VERIFICATION TEST.NoGo To 33. (D65) CAN C BUS (+) CIRCUIT OPEN

Turn the ignition off.Disconnect the TIPM C1 harness connector.Disconnect the ECM C2 harness connector.Measure the resistance of the (D65) CAN C Bus (+) circuit between the TIPM connector and the ECM connector.Is resistance below 5.0 ohms?YesGo To 4NoRepair the (D65) CAN C Bus (+) circuit for an open.Perform the ECM VERIFICATION TEST.4. (D64) CAN C BUS (-) CIRCUIT OPEN

Measure the resistance of the (D64) CAN C Bus (-) circuit between the TIPM connector and the ECM connector.Is resistance below 5.0 ohms?YesReplace and program the Engine Control Module in accordance with the service information.Perform the ECM VERIFICATION TEST.NoRepair the (D64) CAN C Bus (-) circuit for an open.Perform the ECM VERIFICATION TEST.