John Deere 003033.02 – BRC / CAB: Left Brake Pedal Switch Voltage Issue

The Brake Control Unit (BRC) or Cab Control Unit (CAB) has detected an abnormal voltage signal from the left brake pedal switch. The FMI 02 identifier indicates the data is erratic, intermittent, or incorrect. This voltage issue may affect the proper operation of the braking system or related functions.

• 8130
• 8230
• 8330
• 8430
• 8530
• 9330
• 9430
• 9530
• 9630
• 5E Series
• 5M Series

1. 1

   Restart the engine or cycle the key switch to see if the fault clears, as the voltage issue may be intermittent

2. 2

   Check for other active fault codes that might indicate a broader electrical issue, such as low system voltage (e.g., BRC 158.4) or sensor supply voltage problems

3. 3

   Inspect relevant fuses (e.g., fuse F30) for blown circuits

4. 4

   Visually inspect the wiring harness and connectors leading to the left brake pedal switch for any signs of damage, corrosion, or loose connections. For some models, a repair kit for the connector may be available.

5. 5

   Verify switch operation by checking for continuity with a multimeter as the brake pedal is depressed and released

6. 6

   Check for proper mechanical operation and adjustment of the brake pedal and switch

1. 1

   Ensure safety

   Park the machine on a level surface, engage the park brake, and disconnect the battery.

2. 2

   Locate the switch

   Locate the brake pedal switch at the top of the brake pedal arm assembly.

3. 3

   Disconnect and remove

   Disconnect the electrical connector from the switch. The switch is typically held in place by clips or a threaded body with nuts. Squeeze the retaining tangs to release it or unscrew it from its bracket.

4. 4

   Install the new switch

   Install the new switch, ensuring it is properly seated and secured.

5. 5

   Reconnect and test

   Reconnect the electrical connector and the battery. Start the machine, test the brake light function, and check if the fault code returns.

6. 6

   Calibrate system

   For some models and controllers, perform a calibration procedure after replacing the switch (e.g., CAB 524169.13 Left brake pedal calibration fault). This often requires specialized tools like the John Deere Service ADVISOR.