John Deere 3213.12 – TEC (Tractor Equipment Control Unit): ISO BUS CAN BUS Fault Cab Roof Module (TEC)

Communication failure, missing message, or high error rate on the ISOBUS CAN network. The system is detecting that the CAN BUS messages between the Cab Roof Module and the TEC are either corrupted, interrupted, or failing to transmit properly.

• 6110M
• 6120M
• 6130M
• 6145M
• 6155M
• 6175M
• 6195M
• 6110R
• 6120R
• 6130R
• 6145R
• 6155R
• 6175R
• 6195R
• 6215R

1. 1

   Restart the tractor engine to verify if the active Service Code reappears, as CAN BUS communication glitches can sometimes be corrected by resetting messages during a restart.

2. 2

   Disconnect any implements, aftermarket monitors, or non-compliant devices plugged into the ISOBUS connector to rule out a faulty implement crashing the CAN network.

3. 3

   Inspect the ISOBUS implement connector at the rear of the tractor for dirt, water ingress, corrosion, or bent pins.

4. 4

   Check the CAN BUS wiring harness routing from the TEC to the Cab Roof Module for chafing, pinch points, or loose ground connections.

5. 5

   Test the CAN BUS circuit for proper voltage (typically around 2.5V on CAN High and CAN Low) and verify the terminating resistors in the circuit are intact (usually 60 ohms across the network when powered down).

1. 1

   Disconnect Power

   Turn off the tractor and disconnect the battery before servicing the CAN network to prevent electrical spikes.

2. 2

   Isolate the Fault

   If the code cleared when the implement was disconnected during diagnostics, the fault lies within the implement's wiring or its compatibility. Repair the implement harness.

3. 3

   Clean and Repair Connectors

   If the tractor's ISOBUS receptacle is corroded, use electrical contact cleaner to clean the pins. Replace the receptacle if pins are burnt or heavily degraded.

4. 4

   Repair Harness

   If wiring damage is found between the Cab Roof Module and the TEC, repair the broken/chafed wires using OEM-approved weather-pack connectors and heat shrink.

5. 5

   Software Update

   If the wiring and connectors are perfectly intact, the TEC or Cab Roof Module may be experiencing an internal software lockup. A John Deere dealer will need to connect Service ADVISOR to flash/update the TEC Control Software to the latest version.

6. 6

   Module Replacement

   If software updates fail and the CAN BUS lines test good, the internal CAN transceiver in either the Cab Roof Module or the TEC has failed. Replace the faulty module and have a dealer calibrate it to the tractor.