John Deere 639.12 – Network-wide (e.g., AIC, BCU, CCU, EPC, XMA, XMC, TMA, ACU, UIC): Vehicle CAN BUS Fault

A control unit's CAN Bus error limit has been exceeded due to too many incorrect CAN BUS messages or a general problem in the connection to the CAN network. This is typically caused by a short circuit, an open circuit, or excessive CAN Bus traffic overloading the network.

• 6110M
• 6120M
• 6130M
• 6145M
• 6155M
• 6175M
• 6195M
• 6110R
• 6120R
• 6130R
• 6145R
• 6155R
• 6175R
• 6195R
• 6215R
• 8225R
• 8235R
• 8245R
• 8260R
• 8270R
• 8285R
• 8295R
• 8310R
• 8320R
• 8335R
• 8345R
• 8360R
• 8370R
• 8400R
• 8310RT
• 8335RT
• 8360RT
• 9470RT
• 9520RT
• 9570RT
• 9230
• 9330
• 9430
• 9530
• 9630
• 6145J
• 6165J
• 6180J
• 6205J
• 6120-6420
• 6230
• 6330
• 6430
• 260E
• 310E
• 944K
• E360
• E360LC

1. 1

   Verify if the 000639.12 code is currently active, which indicates a live CAN communication loss.

2. 2

   Visually inspect the CAN Bus wiring harness and connectors for chafing, corrosion, or loose pins that could cause a short or open circuit.

3. 3

   If the code is stored but not active, check the affected control unit for an incorrect stored configuration.

4. 4

   Evaluate the control unit's processing load and check if any recent software updates may have caused a software execution delay.

1. 1

   Harness Repair

   If physical damage (short/open) is found during the diagnostic inspection of the CAN Bus lines, repair or replace the affected section of the wiring harness.

2. 2

   Software Update

   If no physical wiring fault is found, upload the newest software version to the affected control unit (e.g., the CCU or AIC).

3. 3

   Broadcast Configuration

   After updating the software, cycle the machine's ignition ON and OFF. This forces the updated control unit to broadcast its configuration to the other controllers on the network.

4. 4

   Rollback/Reinstall

   If the problem persists and was preceded by a recent update, roll back the recent software updates to determine if they caused the execution delay, or reinstall the software to correct underlying corruption.

5. 5

   Clear Codes and Test

   Clear the stored diagnostic trouble codes and operate the machine to ensure the CAN Bus error limit is no longer being exceeded.