Cat® Grade Control Cross Slope System for Motor Graders Caterpillar

Illustration 1	g06086227
M, M2, and M3 Series Data Link Communication System

Electronic communication between the Transmission/Chassis ECM, the Implement ECM, and the other control modules on the machine is conducted over data link circuits. The data link circuits allow the sharing of information with other electronic control modules. The data link circuits are bidirectional. The data link circuit allows the ECM to send information and to receive information.

The electronic communication system consists of two types of data link systems.

• Cat^® Data Link (CDL)

• SAE J1939 CAN Data Link (A&B)

The two types of data links are the main structure for communication between all the control modules on the machine.

The SAE J1939 CAN Data Link circuit is mostly used for faster operational communication between the control modules on the machine. The Cat Data Link is used for some of the internal communication that does not require the faster speeds and is used for communication with external devices such as the Cat ET service tool.

Cat^® Data Link

The Cat Data Link is an input/output of the ECM. The data link uses the connector for the service port to communicate with the Cat ET. A data link connection is provided for the product link.

The data link is bidirectional. The bidirectional link allows the ECM to input information and output information. The data link consists of internal ECM circuits, the related harness wiring, the service tool connector, and the connector for the product link.

• The ECM receives commands from the Cat ET to change the operating modes. The Cat ET will read the service codes that are stored in the memory of the ECM. The Cat ET will clear the service codes that are stored in the memory of the ECM.

• The ECM sends the input and the output information to the Cat ET.

Note: An electronic control module that uses the Cat Data Link will have a module identifier. The MID for the Machine Electronic Control Module is 039.

CAN Data Link

A data link is required for communication with the service tool (Cat ET) and the electronic control modules as well as instrument clusters and other devices that use this communications protocol. The data link is not used to broadcast any diagnostic information. In Cat Grade System, CAN Data Link Communications is used to communicate between the Inclination, Blade Slope, and the Blade Rotation Sensors and the Implement ECM.