John Deere 523842.04 – HCC / HCU: Rear Hitch Load/Depth Sensor or Sensitivity Potentiometer Circuit Voltage Low

The control unit is receiving a signal voltage from the load/depth sensor or sensitivity potentiometer that has dropped below the minimum acceptable threshold. This is typically caused by a short circuit to ground, an open circuit in the wiring harness, or a complete internal failure of the potentiometer/sensor itself.

• 6110M
• 6120M
• 6130M
• 6145M
• 6155M
• 6175M
• 6195M
• 5090M
• 5100M
• 5100MH
• 5100ML
• 5115M
• 5065M
• 5075M
• 5085M
• 5115ML
• 5095M
• 5095MH
• 5105M
• 5015ML
• 5225
• 5325
• 5425
• 5525
• 5625
• 5725
• 6090MC
• 6100MC
• 6110MC
• 6090RC
• 6100RC
• 6110RC

1. 1

   Visually inspect the wiring harness routing from the HCU/HCC to the rear hitch load/depth sensor or sensitivity potentiometer for rubbed-through insulation, pinched wires, or disconnected plugs.

2. 2

   Disconnect the sensor/potentiometer and inspect the connector pins for corrosion, moisture, or pushed-back terminals.

3. 3

   Test the positive supply lead and the signal lead for continuity back to the Hitch Control Unit.

4. 4

   Test the signal wire for a short-to-ground, which will pull the voltage down and trigger the fault.

5. 5

   If wiring tests good, evaluate the potentiometer/sensor for internal failure.

1. 1

   Power Down

   Turn off the tractor, remove the key, and ensure the rear hitch is fully lowered to the ground to relieve any hydraulic pressure or mechanical tension.

2. 2

   Access the Sensor

   Depending on the model, locate the defective sensor. For draft/load sensors, they are typically located on the rear draft link pins or rockshaft housing. For sensitivity potentiometers, lift the right-hand cab console slightly to access the load/depth connector under the hitch control dials.

3. 3

   Remove the Defective Component

   Disconnect the electrical connector. Unbolt or unclip the sensor/potentiometer from its mounting bracket.

4. 4

   Install the New Part

   Mount the replacement sensor/potentiometer and reconnect the wiring harness.

5. 5

   Reassembly

   Secure the console or rear housing covers.

6. 6

   Calibration

   Perform a rear hitch calibration via the tractor's diagnostic monitor. The HCU/HCC needs to learn the new minimum and maximum voltage sweeps of the replacement part to prevent secondary out-of-calibration codes.