John Deere 2221.09 – CCU (Chassis Control Unit): Incorrect CAN Bus Message, Information from PLC Control Software

Data transfer problem on the machine's Controller Area Network (CAN BUS) indicating intermittent or non-existent reception of messages sent by the Programmable Logic Controller (PLC), typically due to a physical communication disruption.

• 6110R
• 6120R
• 6130R
• 6145R
• 6155R
• 6175R
• 6195R
• 6215R
• 6230R
• 6250R
• 6090M
• 6100M
• 6110M
• 6120M
• 6130M
• 6140M
• 6145M
• 6155M
• 6175M
• 6195M
• 6090MC
• 6100MC
• 6110MC
• 6090RC
• 6100RC
• 6110RC

1. 1

   Inspect the CAN BUS wiring harness between the PLC and the Rear Chassis Control Unit (CCU) for chafing, pinched wires, or loose connections.

2. 2

   Disconnect the CCU and PLC harness connectors and check for pushed-back pins, corrosion, or moisture inside the plugs.

3. 3

   With the battery disconnected, measure the resistance across the CAN High and CAN Low pins to test the terminating resistors (should read approximately 60 ohms; 120 ohms indicates an open circuit or faulty resistor, 0 ohms indicates a short circuit).

1. 1

   Disconnect Power

   Disconnect the negative battery terminal before servicing CAN BUS components to prevent electrical spikes.

2. 2

   Repair Wiring/Connectors

   If the diagnostic checks reveal damaged wiring or corroded pins, repair the harness or replace the damaged pigtail connectors.

3. 3

   Replace Terminating Resistors

   If the resistance test fails and wiring is intact, locate and replace the faulty CAN BUS terminating resistor on the network.

4. 4

   Replace the CCU

   If the wiring harness, connectors, and terminating resistors all test perfectly, remove the mounting hardware, unplug the module, and install the replacement CCU.

5. 5

   Reprogramming

   Use dealer-level software (John Deere Service ADVISOR) to flash the new CCU and calibrate it to the specific tractor's chassis options.