how to resolve U0121 code in Volvo XC60 Second Generation (2018-2024)

Learn how to diagnose and fix U0121 code related to steering angle sensor in Volvo XC60. Step-by-step guide with diagnostic and repair instructions.

Solution

1. Preparation

• Tools Required: OBD-II scanner, multimeter, socket set, torque wrench, screwdrivers.
• Disconnect the vehicle battery to avoid electrical shorts while working on the system.

2. Inspect and Repair Wiring

• Carefully disconnect the steering angle sensor connector.
• Inspect the wiring harness for any signs of wear, fraying, or damage.
• Repair or replace any damaged wires or connectors found during inspection.

3. Replace the Steering Angle Sensor (if necessary)

• Tools Required: Socket set, torque wrench.
• Remove the steering column cover by unscrewing the retaining screws.
• Disconnect the steering angle sensor connector.
• Unbolt the sensor from its mounting position (usually has 2-3 screws).
• Install the new steering angle sensor, ensuring it is properly aligned and secured.
• Torque the bolts to the manufacturer's specifications (generally around 5-7 Nm, verify with repair manual).
• Reconnect the sensor connector.

4. Reconnect Battery and Clear Codes

• Reconnect the vehicle battery.
• Use the OBD-II scanner to clear any existing codes from the ECU.

5. Calibration

• Start the vehicle and allow it to idle for a few minutes.
• Follow the manufacturer's procedure to calibrate the steering angle sensor, typically done through the vehicle's diagnostic software or specific calibration procedures.