John Deere 523950.13 – HCC / HCU: Rear Hitch Position Sensor Out Of Range / Rear Hitch Calibration not Performed Correctly / Hitch Calibration Purge Counting Fault

The control module detects that the rear hitch position sensor is operating outside of its calibrated parameters, or when a recent calibration attempt failed. The system requires a set number of purge cycles to learn the sensor's limits and purge air from the hydraulics; if it does not see enough of these cycles, or if the sensor voltage is out of bounds, this code is logged.

• 6110M
• 6120M
• 6130M
• 6145M
• 6155M
• 6175M
• 6195M
• 5090M
• 5100M
• 5100MH
• 5100ML
• 5115M
• 5065M
• 5075M
• 5085M
• 5115ML
• 5095M
• 5095MH
• 5105M
• 5015ML
• 8225R
• 8245R
• 8310R
• 8320R
• 8370R
• 8310RT
• 8335RT
• 9230
• 9330
• 9430
• 9530
• 9630

1. 1

   Inspect the Rear Hitch Position Sensor and its wiring harness for signs of physical damage, loose connections, or corrosion.

2. 2

   Verify the sensor's functionality using a multimeter. Normal voltage should read 0.5 - 2.0V at Transport Lock (Full Up) and 3.0 - 4.5V at Hitch Down.

3. 3

   Check the hydraulic system for any mechanical binding or low fluid issues that may be preventing the rear hitch from completing its full physical stroke.

4. 4

   Temporarily unplug the draft sensor to isolate the circuit. If the position sensor voltage normalizes, it indicates a short in the draft sensor, as they often share power and ground circuits.

1. 1

   Replace Faulty Components

   If the sensor fails the voltage test or the wiring is damaged, replace the Rear Hitch Position Sensor or repair the harness.

2. 2

   Perform Hitch Calibration

   Whether you replaced the sensor or the code was triggered by a lost calibration, you must perform a rear hitch calibration.

3. 3

   Execute Purge Cycles

   Initiate the calibration procedure via the CommandCenter display. The calibration process strictly requires three full down-to-full-up cycles of the rear hitch. Ensure the hitch travels its absolute full range without interruption so the HCC/HCU can learn the new minimum and maximum sensor values and purge the hydraulic valves.

4. 4

   Clear Codes

   Once calibration is successful, clear the 523950.13 code from the HCC/HCU and verify normal hitch operation.