how to diagnose C1021 code in my Tesla Outback 5th Generation (2015-2019)

Learn how to diagnose and fix C1021 ABS issue in Tesla Outback (2015-2019). Step-by-step guide with symptoms, diagnostic steps, and repair instructions.

Solution

1. Preparation

• Gather necessary tools and safety gear.
• Ensure the vehicle is on a flat surface and secure it with wheel chocks.
• Disconnect the negative battery terminal to prevent electrical shorts.

2. Inspect and Clean Sensors

• Tools Required: Ratchet set, torque wrench, cleaning wipes.
• Locate each wheel speed sensor at the wheel hub assembly.
• Remove the sensor mounting bolts and gently pull the sensor out.
• Clean any debris or corrosion from the sensor tip and the mounting hole.
• Reinstall the sensor and tighten the bolts to the specified torque (usually around 8-10 Nm).

3. Inspect Wiring and Connectors

• Tools Required: Wire brush, multimeter.
• Examine the wiring harness connected to each wheel speed sensor for frays or breaks.
• Use a wire brush to clean any corrosion on the connectors.
• Reconnect any loose or damaged connectors ensuring a secure fit.

4. Replace Faulty Sensors

• Tools Required: Socket set, torque wrench.
• If a sensor is found faulty in the resistance test, procure a replacement sensor.
• Remove the old sensor by unscrewing it from the hub.
• Install the new sensor in reverse order, ensuring it is securely mounted and torqued properly.

5. Reconnect Battery and Test

• Reconnect the negative battery terminal.
• Clear any codes using the OBD-II scanner and take the vehicle for a test drive to monitor for any reoccurring faults.
• Ensure the ABS warning light does not illuminate during or after the test.