how to diagnose C1201 error code in my Toyota Highlander Fourth Generation (2020-present)

Solution

1. Preparation

• Gather tools and parts for the repair.
• Tools Required: OBD-II scanner, multimeter, socket set, torque wrench.
• Safety Warnings: Ensure the vehicle is on a level surface and turn off the ignition before working on the brake system.

2. Addressing Brake Fluid Level

• Sub-steps:
  1. Open the hood and locate the brake fluid reservoir.
  2. Check the fluid level against the "MIN" and "MAX" marks.
  3. If low, add the appropriate brake fluid type as specified in the owner’s manual (usually DOT 3 or DOT 4).
  4. Close the reservoir cap securely.

3. Replacing the Brake Pressure Sensor (if faulty)

• Sub-steps:
  1. Disconnect the negative battery terminal to ensure safety.
  2. Locate the brake pressure sensor, usually situated near the master cylinder.
  3. Disconnect the electrical connector from the sensor.
  4. Remove the sensor using the appropriate socket. Take care to avoid damaging surrounding components.
  5. Install the new brake pressure sensor by reversing the removal steps, ensuring it is torqued to manufacturer specifications (typically around 10-15 ft-lbs).
  6. Reconnect the electrical connector securely.

4. Final System Check

• Sub-steps:
  1. Reconnect the negative battery terminal.
  2. Start the vehicle and monitor the dashboard for any warning lights.
  3. Ensure the brake system operates smoothly by pressing the brake pedal to check for proper feel and response.