John Deere 1231.14 – CCU / TEC / PL1 / PL3 / VCU / XSC: CAN Bus High Error Rate or CAN Bus Off

The control software has detected too many incorrect CAN Bus messages (often on the Drive Train CAN Bus at 1000 kBd, or the Implement CAN Bus / CAN 2), which exceeds the programmed error limit. This points to a general communication failure, data collision, or physical connection problem on that specific Controller Area Network (CAN).

• 6110M
• 6120M
• 6130M
• 6145M
• 6155M
• 6175M
• 6195M
• 6110R
• 6120R
• 6130R
• 6145R
• 6155R
• 6175R
• 6195R
• 6215R
• 6230
• 6330
• 6430
• 9330
• 9430
• 9530
• 9630
• 744K 4WD Loader
• 204L Compact Loader
• 304L Compact Loader
• 260E Articulated Dump Truck
• 310E Articulated Dump Truck

1. 1

   Visually check all Drive Train or Implement CAN Bus wiring for chafing, damage, loose connections, or corrosion.

2. 2

   Ensure the CAN bus terminating resistors are intact and reading the correct resistance (typically 60 ohms across the bus when the battery is disconnected).

3. 3

   Use John Deere Service ADVISOR or a compatible diagnostic tool to monitor CAN Bus traffic to identify which specific module is dropping offline or flooding the network.

4. 4

   Check the functionality of all control units connected to the affected CAN Bus. Isolate modules one by one to see if a specific control unit is pulling the CAN bus down.

1. 1

   Power Down

   Turn off the machine and disconnect the battery to safely work on the CAN network.

2. 2

   Harness Repair

   Locate the main CAN bus harness connecting to the CCU (or TEC/VCU). Repair or replace any damaged wiring, corroded pins, or faulty connectors found during the visual inspection.

3. 3

   Secure Connections

   Ensure all harness connections are properly seated and free of moisture or debris.

4. 4

   Module Replacement

   If diagnostic testing isolated a specific control unit (such as the CCU) as the source of the communication errors, replace that faulty control unit.

5. 5

   Reassemble and Clear Codes

   Reconnect the battery, turn the key on, and clear the diagnostic trouble codes using Service ADVISOR.

6. 6

   Test Operation

   Operate the machine to verify that full functionality has returned and the 001231.14 code does not reset.