John Deere HCU001873.13 – HCU: HCU Calibration Fault/Rear Hitch Position Sensor Circuit

The Hitch Control Unit (HCU) has detected an issue with the rear hitch position sensor's calibration data. This fault indicates that the rear hitch position sensor requires calibration, often due to a failure to calibrate or an unsuccessful calibration attempt. The system typically responds by limiting the function of the rear hitch.

• 5225
• 5625
• 5085M
• 5115M
• 7810
• 7630
• 7730
• 7830
• 7930
• 9430
• 9530
• 9630
• 8230T
• 8330T
• 8430T

1. 1

   Verify the hydraulic oil temperature is above 50°C (122°F), as low oil temperature can cause calibration to fail

2. 2

   Cycle the hitch through its full range of motion up and down at least three to five times to purge any cold oil from the hitch valve

3. 3

   Recall, record, and clear any other diagnostic trouble codes for the HCU

4. 4

   Visually inspect the wiring and connectors for the rear hitch position sensor for any signs of damage or corrosion

1. 1

   Prepare the tractor

   Ensure the hydraulic oil is at operating temperature (above 50°C / 122°F). Add 136-226 kg (300-500 lbs) of weight to the rear hitch. Set the engine speed to approximately 1900 RPM and ensure the transport lock is off.

2. 2

   Enter calibration mode

   Access the hitch calibration mode through the tractor's diagnostic interface or CommandCenter. This may require entering a technician mode.

3. 3

   Calibrate the hitch position sensor

   Move the hitch to its fully lowered position and then to its fully raised position. Hold the control lever in each position until the value is stored to establish the upper and lower limits of travel.

4. 4

   Calibrate the draft sensors

   Raise and lower the hitch to specific mid-points as directed by the display to calibrate the draft sensors.

5. 5

   Save the calibration

   Once all steps are complete, save the new calibration data when prompted. The display should indicate success (e.g., 'HCAL — Calibration Complete' or 'EOC — End Of Calibration').

6. 6

   Verify the repair

   Cycle the hitch through its full range of motion. If fault code HCU001873.13 returns, perform a circuit test on the rear hitch position sensor and its wiring. Replace the sensor if it is found to be faulty.