John Deere 1872.04 – SCO: Front Hitch Position Sensor Circuit Supply Voltage Low

The control module has detected that the supply voltage to the front hitch position sensor has dropped below the acceptable threshold. This typically indicates a short to ground in the sensor wiring, a damaged wiring harness, a blown fuse, or an internal short within the sensor itself pulling the reference voltage down.

• 6110R
• 6120R
• 6130R
• 6145R
• 6155R
• 6175R
• 6195R
• 6215R
• 8225R
• 8245R
• 8270R
• 8295R
• 8320R
• 8335R
• 8345R
• 8370R
• 8400R
• 7200R
• 7210R
• 7215R
• 7230R
• 7250R
• 7260R
• 7270R
• 7290R
• 7310R

1. 1

   Inspect the wiring harness and connectors leading to the front hitch position sensor for physical damage, corrosion, pinched wires, or accumulated debris.

2. 2

   Check the fuses that supply power to the SCO controller and its sensor circuits (depending on the model, check fuses such as F12, F24, F29, or F51).

3. 3

   Disconnect the sensor, turn the key to the ON position (engine off), and measure the supply voltage at the harness connector. If 5V is present, the sensor is likely shorted internally. If low or zero, there is a wiring issue.

4. 4

   Ohm test the wiring harness from the sensor connector back to the SCO module pins to locate any shorts to ground.

1. 1

   Power Down

   Turn off the tractor, remove the key, and disconnect the battery ground cable to protect the SCO module.

2. 2

   Access the Sensor

   Locate the front hitch position sensor (a rotary angle sensor mounted on the front hitch linkage/casting).

3. 3

   Wiring Repair (If Applicable)

   If the diagnostic checks revealed a short to ground in the harness, repair the damaged wire or replace the affected harness section.

4. 4

   Sensor Replacement (If Applicable)

   Disconnect the electrical connector from the sensor. Remove the mounting hardware securing the sensor (and the sensor plate, if damaged) to the hitch assembly. Install the new rotary position sensor, ensuring the linkage arm is correctly indexed to the hitch movement. Secure the mounting hardware and reconnect the electrical connector.

5. 5

   Calibration

   Reconnect the battery and turn the key ON. Navigate to the tractor's CommandCenter display. You must perform a Front Hitch Calibration procedure so the SCO module can learn the new sensor's minimum and maximum voltage limits corresponding to the hitch's physical travel.

6. 6

   Clear Codes

   Clear the 001872.04 fault code and test the front hitch through its full range of motion to verify the repair.