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

Generated when a control unit receives an excessive number of incorrect CAN BUS messages or detects a general communication failure on the network, indicating a severe breakdown in data transmission integrity usually caused by electrical interference, faulty wiring, a failed terminating resistor, or a defective module shorting the network.

• 6110R
• 6120R
• 6130R
• 6145R
• 6155R
• 6175R
• 6195R
• 6215R
• 6230R
• 6250R
• 7200R
• 7215R
• 7230R
• 7250R
• 7270R
• 7290R
• 8225R
• 8245R
• 8270R
• 8295R
• 8320R
• 8345R
• 8370R
• 8400R

1. 1

   Inspect CAN BUS wiring and connectors leading to the CSC module for signs of chafing, corrosion, or loose pins.

2. 2

   Test terminating resistors with the battery disconnected by measuring resistance across the CAN High and CAN Low pins (a healthy network reads ~60 ohms; 120 ohms indicates a missing/failed resistor, near 0 ohms indicates a short).

3. 3

   Isolate the faulty module by disconnecting the CSC module to see if the 000639.14 error rate drops on the diagnostic tool, which would indicate the CSC is internally shorted.

4. 4

   Check for software updates to verify if there is a firmware update available for the CSC, as software glitches can cause message overflow.

1. 1

   Power Down

   Turn off the tractor and disconnect the negative battery cable to prevent electrical spikes during repair.

2. 2

   Replace Terminating Resistors

   If your multimeter test revealed a resistor failure, locate the CAN bus terminators (often found at the ends of the chassis or implement harnesses) and plug in a replacement.

3. 3

   Repair Harness

   If the wiring leading to the cab suspension module is damaged, splice and heat-shrink the broken CAN wires, ensuring the twisted-pair configuration is maintained to block electromagnetic interference.

4. 4

   Replace the CSC Module

   If the wiring and resistors are intact but the CSC is crashing the bus, remove the mounting hardware for the Cab Suspension Controller, disconnect the harness, and install the new module.

5. 5

   Reconfigure and Calibrate

   Reconnect the battery. Use John Deere Service ADVISOR to clear the 000639.14 code. If the CSC was replaced, you must flash the module with the latest software and perform the cab suspension bleeding and calibration process so the cab can find its level position.