John Deere 522581.09 – CCU: CAN BUS Message Issue With Communication Between the Modules

The CCU is failing to receive CAN bus messages from the CSM (Cab Switch Module) control software. The CCU expects regular updates regarding the switch status for turning on the front-wheel drive (MFWD / Auto Mode), but the reception of one, several, or all expected CAN messages is intermittent or non-existent.

• 6110R
• 6120R
• 6130R
• 6145R
• 6155R
• 6175R
• 6195R
• 6215R
• 6R Series
• 7R
• 8R
• 9R

1. 1

   Check for other active codes in both the Rear Chassis (CCU) and the Cab Switch Module (CSM). A CSM code will take priority if the module itself is failing to register the switch state.

2. 2

   Inspect all CAN bus wiring and connections between the CCU and the CSM for signs of damage, loose pins, or corrosion.

3. 3

   Verify the physical integrity and circuit of the front-wheel drive (MFWD) automatic mode switch.

4. 4

   Test the CAN bus network using a CAN bus analyzer or multimeter for intermittent connections, electrical interference, or data transfer issues.

5. 5

   Ensure both the CCU and CSM control software are updated to the latest versions to rule out software-related CAN message processing errors.

1. 1

   Power Down

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

2. 2

   Access the Modules

   Locate the Cab Switch Module (CSM) in the cab (often integrated into the CommandARM or right-hand console) and the Chassis Control Unit (CCU).

3. 3

   Harness Inspection & Repair

   Disconnect the harness connectors at both the CSM and CCU. Inspect the pins for spread, corrosion, or push-back. Perform a continuity test on the CAN High and CAN Low wires between the two modules. Repair or replace any compromised wiring or connectors.

4. 4

   Switch Replacement

   If the wiring is intact but the CSM is registering an open circuit at the MFWD switch, replace the switch.

5. 5

   Module Replacement/Reprogramming

   If the wiring, connectors, and switches are all in good working order, the issue likely lies within the CSM failing to transmit, or the CCU failing to receive. Consult a John Deere dealer to flash the latest software or replace the faulty module. Note: New modules will require dealer calibration/programming.