CAN Bus

Accessing Controller Area Network (CAN) bus information page displays status of communication between the control units on CAN bus. Machine CAN bus connects control units such as engine, hydraulics, and transmission.

Network Status

• Active - System is working as expected. In addition to display, at least one control unit is connected and communicating on CAN bus.
• Inactive - Display is not communicating with any other control units on CAN bus. If display is only control unit on CAN bus, Total Message Count increases, but network status is inactive.
• Error - Display is not communicating with CAN bus.

Message Count

Message count is number of messages sent over CAN bus. When machine is running, this value counts up continuously since there are always messages sent on CAN bus.

CAN Hi and CAN Lo Voltage

Peak voltage is highest average voltage that has occurred since last cold boot. Peak CAN high and peak CAN low voltages normally range between 1.8 and 3.3 Volts.

NOTE: A cold boot occurs after display has been off for 24 hours or all power has been disconnected from display.

Bus Utilization

If a control unit or implement is not running as expected, bus utilization of 45% or higher could be the reason. Some devices cannot send and receive all necessary messages if bus load is too high.

NOTE: Some ISOBUS implements do not work with bus loads higher than 25%.

Unplugging implements or GPS receivers can reduce bus utilization.

Baud Rate

Baud rate indicates how fast the CAN bus is working. Any control unit connected to this system must work at 500 kbd. Any device operating at a different baud rate does not function properly.

CAN bus Status

• Active - CAN bus is running without any problems.
• Inactive - CAN bus is not communicating as expected and has stopped.
• Error - CAN bus errors have occurred.

Error Counts

If one of these errors occurs, display records number of times it happens.

Passive Error Count - If value counts up higher than zero, a control unit on CAN bus did not receive all messages. Important information might have been lost, most likely due to high CAN bus utilization.

CAN bus Warn Count - If value counts up higher than zero, a control unit on CAN bus has issues.

CAN bus Off Count - If value counts up higher than zero, a control unit on CAN bus has issues. It missed a certain number of messages and does not receive messages anymore. Important information has been lost. It most likely occurs in combination with high CAN bus utilization.

Overrun Error Count - Indicates that applications or control units on CAN bus receive messages faster than they can process them. The result is missing messages and system malfunctions. It most likely occurs in combination with high CAN bus utilization.