John Deere 1673.02 – HCC or HCU: Rear Hitch Position Sensor Circuit Voltage Fault

The control module detects that the voltage signal from the rear hitch position sensor (rockshaft position sensor) is out of the expected range. This indicates that the sensor is damaged, the wiring is compromised, or the system has lost its calibration. When active, the rear hitch function is degraded, allowing only manual raising or lowering without the ability to set specific hitch height limits.

• 6110R
• 6120R
• 6130R
• 6145R
• 6155R
• 6175R
• 6195R
• 6215R
• 8130
• 8230
• 8330
• 8430
• 8530
• 8225R through 8370R
• 7610
• 7710
• 7810
• 7185J
• 7195J
• 7205J
• 7210J
• 7225J
• 5085M through 5115M

1. 1

   Inspect the rear hitch position sensor and its wiring harness for physical damage, corrosion, or loose connector pins.

2. 2

   Measure the sensor's output voltage (should read between 0.5V - 2.0V at the transport lock position, and 3.0V - 4.5V when the hitch is fully down).

3. 3

   Perform a Draft Sensor Isolation Test by unplugging the draft sensor to see if the position sensor suddenly starts reading correctly, which indicates the draft sensor is shorting the shared circuit.

1. 1

   Relieve Pressure

   Ensure the tractor is turned off, the key is removed, and the rear hitch is fully lowered to the ground to relieve hydraulic pressure and prevent the arms from dropping.

2. 2

   Disconnect Wiring

   Unplug the wiring harness connector from the rear hitch position sensor.

3. 3

   Remove Sensor

   Unbolt the linkage arm connected to the sensor and remove the sensor from its mounting bracket on the rockshaft/lift cylinder assembly.

4. 4

   Install New Sensor

   Mount the new sensor, reattach the mechanical linkage, and plug in the wiring harness.

5. 5

   Perform Hitch Calibration

   Perform a Hitch Calibration procedure (245-HCU-001) via the tractor's CommandCenter display or diagnostic service tool so the system learns the new sensor's upper and lower limits.