John Deere 524162.31 – CCU (Chassis Control Unit): Left Brake Pedal Signal Fault

The control unit is receiving an erratic, out-of-range, or missing electrical signal from the left brake pedal's position sensor (potentiometer). When this occurs, the tractor's software may function in a limited capacity, and features like automatic MFWD (Mechanical Front Wheel Drive) or differential lock may temporarily disengage or act erratically.

• 6110M
• 6120M
• 6130M
• 6145M
• 6155M
• 6175M
• 6195M
• 6090MC
• 6090RC
• 6100MC
• 6100RC
• 6110MC
• 6110RC

1. 1

   Inspect Connections: Check the wiring harness, signal lead, and power supply to the left brake pedal potentiometer for physical damage, loose connections, or corrosion.

2. 2

   Test Potentiometer Output: Use a multimeter to measure the voltage at the signal input. A reading consistently below 0.25 volts indicates a low voltage fault, meaning the potentiometer is likely dead or not receiving proper supply voltage.

3. 3

   Verify Power Supply: Ensure the sensor is receiving the correct reference voltage from the CCU.

4. 4

   Physical Inspection: Verify that the sensor/switch hasn't been physically bumped out of its mounting bracket, which is a common issue that causes the CCU to think the brake is being applied.

1. 1

   Park and secure tractor

   Park the tractor safely, turn off the engine, and remove the key.

2. 2

   Locate sensor

   Locate the left brake pedal position sensor (potentiometer) near the pivot point of the brake pedal assembly.

3. 3

   Disconnect harness

   Disconnect the electrical wiring harness from the sensor.

4. 4

   Remove sensor

   Remove the mounting hardware holding the faulty sensor in place and remove the unit.

5. 5

   Install new sensor

   Install the new replacement sensor and secure it to the bracket.

6. 6

   Reconnect harness

   Reconnect the electrical harness.

7. 7

   Calibrate sensor

   Perform a 'Left Brake Pedal Sensor Calibration' using the tractor's CommandCenter or diagnostic service tool. The CCU must learn the new sensor's zero and fully-depressed voltage values.

8. 8

   Clear codes and test

   Clear the CCU fault codes and test drive to ensure the brake lights and differential lock function normally.