PAN GP-OIL 3845029 - Caterpillar

Illustration 1 g01315688
M Series Data Link Communication System
The Transmission/Chassis ECM will use two data links for communication between the other electronic control modules that are on the machine. The data link also allows communication with service tools. The data link is bidirectional. The Transmission/Chassis ECM can send information. The Transmission/Chassis ECM can also receive information. The data link is not a visible component. The data link consists of internal ECM circuits, the related harness wiring, and the harness connectors.The Transmission/Chassis ECM communicates over the two data links that are present on the machine. The two types of systems are listed below.Cat Data Link - The Cat data link is used to send system status information between control modules and the Caterpillar Electronic Technician (ET). All implement system diagnostic codes are activated using the Cat Data Link.SAE J1939 Data Link - The SAE J1939 Data Link is a high speed data link. The J1939 Data Link is used for high speed communication between the Transmission/Chassis ECM and the control modules of other machine systems. In the event of a failure of the SAE J1939 Data Link system, the Cat Data Link is used as a backup system for operational communication.Data Link Diagnostics
Both of the data link systems on the machine are monitored by the Transmission/Chassis ECM for abnormal internal or for abnormal external circuit conditions. The ECM will activate diagnostic codes for a specific control module and the data link circuit when an abnormal condition is detected.When the Transmission/Chassis ECM detects an abnormal condition in a data link circuit, the ECM will activate a "companion" diagnostic code along with the diagnostic code for the involved control module in order to alert the technician to which data link system is involved. The companion codes for the implement system are listed below:CID 0247 - FMI 09 or FMI 14 - SAE J1939 Data LinkCID 0248 - FMI 09 or FMI 14 - Cat Data LinkAn example of how the companion codes are used by the Transmission/Chassis ECM for the data link circuits: The Transmission/Chassis ECM is communicating with the Implement ECM over the SAE J1939 Data Link circuit, however, some expected data is not being communicated. The Transmission/Chassis ECM will activate the CID 0596 FMI 14 diagnostic code (Special Instruction - not receiving expected information) for the Implement ECM. The Transmission/Chassis ECM will also activate the CID 0247 - FMI 14 companion diagnostic code (SAE J1939 Data Link) in order to indicate which data link circuit is involved. The companion diagnostic code will clear when the primary diagnostic code is cleared.A CID 0247 or a CID 0248 companion diagnostic code will always be activated when any of the following module communication codes is activated by the Transmission/Chassis ECM.CID 0588 FMI 09 - Monitoring SystemCID 0596 FMI 09 - Implement ECMCID 0590 - Engine ECM