John Deere 1873.02 – HCC (Hitch Control Computer / Module) / HCU: Rear Hitch Position Sensor Circuit Voltage Fault / Rear Hitch Position Sensor Out Of Range

The Hitch Control Unit (HCU) or Hitch Control Computer (HCC) has detected a voltage signal from the rear hitch position sensor that is outside of the expected range. This prevents the control unit from accurately determining the position of the rear hitch, which can lead to a loss of automatic hitch functions. This condition typically indicates a problem with the sensor itself, damaged wiring, or a poor connection to the control module.

• 6110M
• 6120M
• 6130M
• 6145M
• 6155M
• 6175M
• 6195M
• 6110R
• 6120R
• 6130R
• 6145R
• 6155R
• 6175R
• 6195R
• 6215R
• 5090M
• 5100M
• 5100MH
• 5100ML
• 5115M
• 5065M
• 5075M
• 5085M
• 5115ML
• 5095M
• 5095MH
• 5105M
• 5015ML
• 7610
• 7710
• 7810
• 7630
• 7730
• 7830
• 7930
• 7185J
• 7195J
• 7205J
• 7210J
• 7225J
• 8130
• 8230
• 8330
• 8430
• 8530
• 8225R through 8370R
• 9230
• 9330
• 9430
• 9530
• 9630

1. 1

   Restart the engine to verify if the active Diagnostic Trouble Code (DTC) reappears.

2. 2

   Check the wiring harness and connectors going to the Rear Hitch Position Sensor for signs of physical damage, loose connections, or corrosion.

3. 3

   Measure the sensor's output voltage to ensure it is within the specified range (e.g., Transport Lock should read 0.5-2.0V, and Hitch Down should read 3.0-4.5V).

4. 4

   Unplug the draft sensor (usually located behind the right-hand lift cylinder) to see if the position sensor starts working again; if it does, the fault may actually be a short in the draft sensor circuit.

1. 1

   Relieve Pressure

   Turn off the tractor, lower the hitch completely (if possible), and relieve hydraulic pressure before working near the rockshaft/lift cylinders.

2. 2

   Locate the Sensor

   Find the Rear Hitch Position Sensor, which is typically mounted on the rear rockshaft or near the right-hand lift cylinder.

3. 3

   Repair Wiring

   If the diagnostic checks revealed chafed wires or corroded connector pins, repair the wiring harness and clear the codes.

4. 4

   Replace the Sensor

   If the wiring is intact but the voltage remains out of range, remove the mounting hardware and replace the faulty Rear Hitch Position Sensor.

5. 5

   Calibrate the Hitch

   After replacing the sensor, a hitch calibration must be performed so the HCU/HCC can learn the new sensor's upper and lower voltage limits. This can be done via the tractor's CommandCenter display or by a John Deere dealer using Service ADVISOR.