John Deere 524195.04 – Rear Chassis Module (PLC): Low Voltage On The Park Lock Pressure Sensor

This diagnostic trouble code is triggered when the control unit detects a voltage of less than 0.3 volts at the signal input for the park lock pressure sensor (designated as component B90). This indicates that the sensor's circuit is either shorted to ground or has an open circuit, which may cause the park lock system to not function correctly and compromise the vehicle's ability to stay securely parked.

• 6110R
• 6120R
• 6130R
• 6145R
• 6155R
• 6175R
• 6195R
• 6215R

1. 1

   Inspect Wiring and Connections: Visually examine the wiring harness and connectors leading to the B90 park lock pressure sensor. Look for any signs of physical damage, corrosion, or loose pins.

2. 2

   Check for Shorts to Ground / Open Circuits: Use a multimeter to inspect the signal circuit for any potential shorts to ground or breaks in the wire (open circuit).

3. 3

   Verify Power Supply: Ensure that the 5-volt reference power supply to the sensor is stable and within the specified voltage range.

4. 4

   Test the Sensor: If the wiring, ground, and 5V reference are all intact, test the functionality of the B90 park lock pressure sensor itself to see if it has failed internally.

1. 1

   Disconnect Power

   Turn off the tractor and disconnect the battery to ensure safety while working on the electrical system.

2. 2

   Repair Wiring (If Applicable)

   If your diagnostic checks revealed chafed wires, shorts to ground, or corroded connector pins, repair the wiring harness or replace the damaged connector pigtail.

3. 3

   Replace the Sensor (If Applicable)

   If the wiring tests perfectly but the signal voltage remains below 0.3 volts, the B90 sensor has failed internally. Remove the faulty park lock pressure sensor from the transmission/valve block and install the new one.

4. 4

   Secure Connections

   Reconnect the sensor harness, ensuring the connection is clean, secure, and free from dirt or moisture contamination.

5. 5

   Clear Codes and Test

   Reconnect the battery, clear the stored fault codes from the PLC, and test the tractor's park lock mechanism to ensure the code does not return and the lock engages/disengages properly.