Case IH 2292 (520329.12) - DEC – DEC (Drivetrain Electronic Control or Diesel Engine Controller): CAN 1 - Bus Mute

A controller on the Controller Area Network (CAN) has stopped transmitting messages. This is typically caused by a physical short between the CAN High and CAN Low lines, or a timeout/defect in an ECU connected to the CAN 1 network.

• MAXXUM T4E
• VESTRUM CVX
• Puma Series Tractors
• Magnum and TG Series Tractors
• Steiger Series Tractors
• Precision Air Carts (2230, 2280, 2330, 3380, 3430)

1. 1

   Inspect the CAN 1 wiring harness for physical damage, frayed insulation, or loose connections.

2. 2

   Test for a short circuit between the CAN High and CAN Low lines using a multimeter.

3. 3

   Verify the main controller (DEC/ECU) is receiving proper 12V power and has a solid ground reference.

4. 4

   Check the resistance of the CAN bus circuit to ensure terminating resistors are intact (typically 60 ohms across CAN High and Low with the battery disconnected).

1. 1

   Power Down

   Turn off the machine, remove the key, and disconnect the battery to prevent electrical shorts.

2. 2

   Isolate the Fault

   Disconnect ECUs on the CAN 1 bus one at a time. If the 'Bus Mute' state resolves (or the bus resistance returns to normal) after unplugging a specific module, that module or its immediate connector is the source of the fault.

3. 3

   Repair Wiring

   If a short is found in the harness between CAN High and CAN Low, repair or replace the damaged section of the wiring harness.

4. 4

   Replace the Controller

   If the wiring is intact but the CAN 1 bus remains muted due to a hardware failure inside the ECU, replace the affected controller (e.g., the DEC or Main Controller).

5. 5

   Reassemble and Clear Codes

   Reconnect all harnesses, restore battery power, and use the Case IH diagnostic tool (EST) to clear the fault codes and verify communication is restored on CAN 1.