John Deere 639.14 – CSM: Vehicle CAN BUS, Very High Error Rate

A network communication error indicating that the reporting control unit is receiving an excessive number of incorrect CAN BUS messages, or it has detected a general connectivity problem (such as a short, open circuit, or severe electrical interference) on the vehicle's CAN BUS network.

• 6110R
• 6120R
• 6130R
• 6145R
• 6155R
• 6175R
• 6195R
• 6215R
• 7R Series
• 8R Series
• 8225R
• 8345R
• 8400R
• 9R Series
• 6M
• 6R
• 7420
• 9330
• 9430
• 9530
• 9630
• S-Series
• S660
• S670

1. 1

   Inspect CAN BUS wiring harness leading to the CSM/Armrest for cuts, abrasions, pinching, or melted insulation, and ensure connectors are properly seated and clean.

2. 2

   Verify termination resistors by measuring resistance across CAN High and CAN Low pins (should be approximately 60 ohms).

3. 3

   Check for electrical interference from improperly spliced aftermarket equipment (like radios or GPS units).

4. 4

   Test network voltage with ignition on; CAN High and CAN Low should rest around 2.5V when idle.

5. 5

   Isolate modules by unplugging them one by one (starting with the CSM) to see if CAN network voltage returns to normal, indicating an internal short.

1. 1

   Disconnect Power

   Disconnect the negative battery cable before servicing the CAN network to prevent short circuits.

2. 2

   Repair Wiring

   If the diagnostic checks revealed chafed or broken wires in the armrest harness, use an OEM wiring repair kit to splice in new wire. Solder and heat-shrink the connections to ensure data transmission integrity.

3. 3

   Clean Connections

   If connectors are corroded, clean the pins with electronic contact cleaner and apply dielectric grease before reconnecting.

4. 4

   Replace Faulty Components

   If a termination resistor tested out of spec (open circuit), replace it. If the CSM was identified as the source of the network crash during the isolation test, remove the armrest trim panels, unbolt the CSM, and install a replacement unit.

5. 5

   Software Update/Reconfiguration

   If a new CSM is installed, or if the wiring was repaired, connect the John Deere Service ADVISOR tool to clear the 000639.14 code. Apply any available firmware updates to the CSM and other control units to ensure software compatibility.