ECM Does Not Communicate with Other Modules
- Wiring and/or electrical connectors
- Cat Data Link
- CAN data link (if equipped)
- Electronic Control Module (ECM)
Note: The procedures have been listed in order of probability. Complete the procedures in the order of the listed test steps.
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Troubleshooting Test Steps | Values | Results |
1. Check for correct installation of the connectors for the ECM J1/P1, J2/P2, and J3/P3. Refer to the diagnostic functional test Troubleshooting, "Electrical Connectors - Inspect" |
ECM |
Result: Connectors are installed incorrectly. Repair: Correct the installation issue. Return to service. Result: Connectors are installed correctly. Proceed to Test Step 2 |
2. Connect Cat ® Electronic Technician (Cat ET) to the service tool connector. |
Cat ET |
Result: Cat ET will not communicate with the ECM.
Proceed to troubleshooting without a diagnostic code Troubleshooting, "Electronic Service Tool Will Not Communicate with ECM." Result: Cat ET communicates with the ECM. Proceed to Test Step 3. |
3. Troubleshoot the Cat Data Link for possible problems. |
Cat Data Link |
Result: Cat Data Link does not connect. Refer to the diagnostic functional test Troubleshooting, "Cat Data Link Circuit - Test". Result: Cat Data Link connects. Proceed to Test Step 4. |
4. Troubleshoot the CAN Data Link (if equipped) for possible problems. |
CAN Data Link |
Result: CAN Data Link does not connect. Refer to the diagnostic functional test Troubleshooting, "CAN Data Link Circuit - Test". Result: CAN Data Link connects. Return to service. |
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