SEAL GROUP (std.) 8P1848 - Caterpillar

Use this procedure to troubleshoot the Data link system. Also use this procedure if a diagnostic code in Table 1 is active or easily repeated.
Table 1
J1939 Code and Description CDL Code and Description Comments
639-9
J1939 Network #1 : Abnormal Update Rate 247-9
J1939 Network #1 : Abnormal Update Rate Communication has been lost to one or more of the devices on the datalink. If multiple devices are not communicating, there is likely a problem with the data link wiring, power, or ground circuits.
639-14
J1939 Network #1 : Special Instruction 247-14
J1939 Network #1 : Special Instruction The affected ECM is missing expected parameters.
1231–9
SAE J1939 Data Link #2 : Abnormal Update Rate 2348–9
SAE J1939 Data Link #2 : Abnormal Update Rate Communication has been lost to one or more of the devices on the datalink. If multiple devices are not communicating, there is likely a problem with the data link wiring, power, or ground circuits.
1231–14
SAE J1939 Data Link #2 Special Instruction 2348–14
SAE J1939 Data Link #2 Special Instruction The affected ECM is missing expected parameters.
1235-9
J1939 Network #3 : Abnormal Update Rate 5856-9
J1939 Network #3 Abnormal Update Rate Communication has been lost to one or more of the devices on the datalink. If multiple devices are not communicating, there is likely a problem with the data link wiring, power, or ground circuits.
1235-14
J1939 Network #3 : Special Instruction 5856-14
J1939 Network #3 : Special Instruction The affected ECM is missing expected parameters.
3360–9
Aftertreatment #1 DEF Controller : Abnormal Update Rate 3820–9
Aftertreatment #1 Diesel Exhaust Fluid Controller : Abnormal Update Rate The #1 Diesel Exhaust Fluid Control Unit (DCU) triggered a CAN communication diagnostic code and shutdown the SCR system. If the Caterpillar Electronic Technician (ET) will not communicate with the ECM, refer to Troubleshooting, "Electronic Service Tool Does Not Communicate" before you begin this procedure. The procedure verifies that electrical power is being supplied to the ECM and to the service tool connector.The Systems Communication Status is located under the diagnostics tab in Cat® ET. Click on the "System Communication Status" option. Once the screen opens up, the information will automatically be loaded from the ECM. If there is an issue with the data link and the data link is repaired, the "Load from ECM" button will have to be clicked again to see the updated status. If there are communication issues between multiple modules, each module can be selected individually to determine which components are having communication issues. If the problem is intermittent, the "View History" button can be clicked to see all of the communication faults that have previously logged.
Table 2
Cat® ET Diagnostic Code Cross Reference to Wiring Schematic
Code Description Data Link
J1939 Network #1 Can A
J1939 Network #2 Can B
J1939 Network #3 Can C -9 Detected Problems:ECM 1 is unable to communicate on the data link.
ECM 1 cannot communicate with other ECM's on the data link, but can communicate with the service tool, indicating a problem with the data link wiring.ECM 1 is unable to