John Deere 1859.31 – SCC / SCU: Radar Not Available

The control module is no longer receiving the expected true ground speed signal from the radar sensor over the CAN BUS network.

• 6110R
• 6120R
• 6130R
• 6145R
• 6155R
• 6175R
• 6195R
• 6215R
• 6190R
• 9470RT
• 9520RT
• 9570RT
• 9230
• 9330
• 9430
• 9530
• 9630
• 7220
• 7320
• 8100
• 8200
• 8300
• 8400

1. 1

   Check the face of the radar sensor for mud, heavy crop debris, or physical damage that could block electromagnetic pulses

2. 2

   Inspect the radar sensor pigtail and main wiring harness connecting to the SCC/SCU for rubbed wires, pulled pins, or corrosion

3. 3

   Verify the sensor is receiving proper operating voltage and has a clean ground using a multimeter

4. 4

   Verify that the CAN BUS lines between the radar sensor and the Rear Chassis Module (SCC) are intact and not shorted to ground or power

1. 1

   Clean the Sensor

   Thoroughly clean the bottom face of the radar sensor. Cycle the tractor's key power to see if the code clears.

2. 2

   Repair Harness

   If wiring damage is found during the diagnostic phase, splice and heat-shrink the broken wires or replace the damaged connector housing/pins.

3. 3

   Replace the Radar Sensor

   If the wiring is intact and the sensor is clean but still unresponsive: Disconnect the negative battery terminal. Unplug the radar sensor connector. Remove the mounting bolts securing the radar sensor bracket to the chassis. Install the new radar sensor, ensuring it is angled correctly toward the ground as per OEM spec. Reconnect the wiring harness.

4. 4

   Clear Codes and Calibrate

   Reconnect the battery. Use a John Deere Service ADVISOR tool or the in-cab CommandCenter display to clear the 001859.31 fault code. A brief test drive may be required for the SCC to recognize the new radar speed signal.