No Response From ECM (Engine Control Module) - Diesel

NO RESPONSE FROM ECM (ENGINE CONTROL MODULE) - DIESEL

No Response From ECM (Engine Control Module) - Diesel:

POSSIBLE CAUSES
- Engine control module power and ground
- (D65) CAN C BUS (+) circuit open
- (D64) CAN C BUS (-) circuit open
- Engine control module

DIAGNOSTIC TEST

1. TEST FOR INTERMITTENT CONDITION
Turn the ignition on.

NOTE: Ensure the IOD fuse is installed and battery voltage is between 10.0 and 16.0 volts.

With the scan tool, select ECU view.

NOTE:
- 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.

Q: Does the scan tool display a red X next to the module?

YES: Go To 2
NO: The 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 GROUND
Check the ECM power and ground circuits. Refer to Computers and Control Systems.

Q: Were any problems found?

YES: Repair as necessary.
Perform the ECM VERIFICATION TEST. Verification Tests
NO: Go To 3

3. (D65) CAN C BUS (+) CIRCUIT OPEN




Turn the ignition off.
Disconnect the TIPM C6 harness connector.
Disconnect the ECM C1 harness connector.
Measure the resistance of the (D65) CAN C Bus (+) circuit between the TIPM connector and the ECM connector.

Q: Is resistance below 5.0 ohms?

YES: Go To 4
NO: Repair the (D65) CAN C Bus (+) circuit for an open.
Perform the ECM VERIFICATION TEST. Verification Tests.

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.

Q: Is resistance below 5.0 ohms?

YES: Replace and program the Engine Control Module.
Perform the ECM VERIFICATION TEST. Verification Tests.
NO: Repair the (D64) CAN C Bus (-) circuit for an open.
Perform the ECM VERIFICATION TEST. Verification Tests.