John Deere 520426.07 – CCU, AIC, OIC, or RLC: Vehicle CAN Bus Error Counter High

Triggered when the error counter for the vehicle's Controller Area Network (CAN) Bus reaches an unusually high level. It indicates persistent communication errors within the network, meaning too many incorrect CAN Bus messages are being transmitted, or no messages are being transmitted at all. This condition forces the control unit to restrict the functionality of systems relying on the CAN Bus to prevent erroneous operations.

• 6110M
• 6120M
• 6130M
• 6145M
• 6155M
• 6175M
• 6195M
• 6110R
• 6120R
• 6130R
• 6145R
• 6155R
• 6175R
• 6195R
• 6215R
• 8225R
• 8245R
• 8270R
• 8295R
• 8320R
• 8335R
• 8345R
• 8370R
• 8400R
• 9470RT
• 9520RT
• 9570RT
• 310K Backhoe Loader
• 210K EP Tractor Loader
• 210L EP Tractor Loader
• 6105M
• 6115M

1. 1

   Inspect the CAN bus wiring harness for physical damage, loose connections, pinched wires, or corrosion at the connectors

2. 2

   Ensure that proper CAN terminating resistors are installed at both ends of the CAN bus network

3. 3

   Check for sources of electrical noise or interference near the CAN bus network, such as damaged alternator diodes or aftermarket electronics

4. 4

   Monitor CAN Bus traffic using diagnostic software (like Service ADVISOR) to identify if an incompatible, malfunctioning, or incorrectly configured device is overloading the network

5. 5

   Verify if the control software is updated to the latest version to address potential CAN message processing bugs

1. 1

   Isolate the Fault

   Disconnect devices on the CAN bus one by one to see if the error counter drops, which will isolate the specific malfunctioning module or harness segment.

2. 2

   Repair Wiring

   Repair or replace any compromised wiring harness segments or corroded connector pins found during the visual inspection.

3. 3

   Replace Terminators

   If a terminating resistor is found to be faulty (a healthy CAN bus should measure roughly 60 ohms across the CAN High and CAN Low pins with the battery disconnected), replace the CAN bus terminator.

4. 4

   Update Software

   Flash the CCU/AIC/OIC with the latest software update via John Deere Service ADVISOR.

5. 5

   Reset and Test

   After resolving the underlying physical or software issues, reset the error counter and clear the DTCs. Operate the machine and monitor the CAN Bus to ensure error rates remain low and normal function is restored.