how to fix C1201 code on Toyota Corolla E140 (2006-2013)

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the negative battery terminal to prevent electrical shorts and ensure safety.

2. Inspect and Clean Wheel Speed Sensors

• Tools Required: Socket set, cleaning brush, brake cleaner.
• Remove the wheel that is experiencing issues.
• Locate the wheel speed sensor on the hub assembly.
• Disconnect the electrical connector of the wheel speed sensor.
• Clean the sensor and mounting area with brake cleaner to remove debris and dirt.
• Reconnect the sensor and ensure it is securely mounted.

3. Replace Faulty Wheel Speed Sensors (if required)

• If the sensors failed the resistance test or are damaged:
  • Tools Required: Socket set, torque wrench.
  • Remove the wheel speed sensor from the hub.
  • Install the new wheel speed sensor and torque it to manufacturer specifications (typically around 7-10 ft-lbs).
  • Reconnect the sensor’s electrical connector.

4. Check ABS Control Module

• If wheel speed sensors are functional, test the ABS control module.
• Tools Required: OBD-II scanner.
• Perform a scan to check for codes after cleaning/replacing sensors.
• If the C1201 code persists, consider replacing the ABS control module.

5. Reconnect Battery and Final Checks

• Reconnect the negative battery terminal.
• Clear all error codes using the OBD-II scanner.
• Test the vehicle to ensure the ABS and traction control systems operate correctly.