John Deere 001877.31 – HCU/HCC: Rear Hitch Fault Detected

The hitch control system has detected a general fault and disabled the rear hitch as a precaution. The FMI 31 identifier indicates that a specific condition exists preventing normal operation, rather than a direct electrical failure like a short or open circuit. This state-based fault means the rear hitch is currently not enabled or available for use.

• 5075M
• 5085M
• 5090M
• 5090R
• 5100M
• 5115M
• 5125R
• 6110M
• 6120M
• 6130M
• 6145M
• 6R 155
• 6R 185
• 7210
• 7720
• 7830
• 8130
• 8230
• 8330
• 8430
• 8530
• 9120
• 9220
• 9320
• 9420
• 9520

1. 1

   Cycle the hitch by fully raising and lowering it three times using the in-cab controls to attempt a system recovery

2. 2

   Cycle tractor power by turning the key switch off, waiting a moment, and restarting to see if the fault clears

3. 3

   Check the hydraulic oil level and top it off if necessary, as low fluid can restrict system functions

4. 4

   Inspect fuses related to the hitch control system, specifically checking Fuse F30

5. 5

   Visually inspect the rear hitch for mechanical issues such as binding linkage or obstructions

6. 6

   Check for damaged wiring or loose connectors on the hitch position sensors and solenoid valves

1. 1

   Retrieve diagnostic codes

   Use a diagnostic scanner to read all active and stored fault codes from the HCU/HCC. Look for accompanying codes that pinpoint the root cause (e.g., sensor voltage out of range, calibration fault).

2. 2

   Address underlying codes

   Diagnose and repair any other present codes first. Common related faults include Hitch Position Sensor Faults (SPN 1873), Hitch Calibration Faults (FMI 13), or Solenoid Valve Faults.

3. 3

   Perform hitch calibration

   If no other faults are found, or after replacing a component, perform a hitch calibration using John Deere Service ADVISOR to teach the control unit the upper and lower limits of the hitch movement.

4. 4

   Inspect and test components

   If the problem persists, test the hitch position sensor for proper voltage and output signal throughout its range. Check the resistance of the hitch control solenoid coils and ensure they receive correct voltage when commanded.