U2128 – Lost Communication with the Steering Angle Sensor.

The ODBII code U2128 indicates a loss of communication with the steering angle sensor, which may affect the vehicle’s stability control and steering response systems.

The severity of ODBII code U2128 is generally considered moderate.

Common Causes For: U2127 Lost Communication with the Steering Angle Sensor.

• Faulty steering angle sensor
• Damaged wiring or connectors
• Poor electrical connections
• Malfunctioning power steering control module
• Software issues or calibration errors
• Low battery voltage
• Interference from other electronic components

Common misdiagnosis for U2128 Lost Communication with the Steering Angle Sensor.

• Faulty Steering Angle Sensor
• Wiring Issues or Short Circuits
• Faulty Body Control Module (BCM)
• Faulty Electronic Power Steering (EPS) Module
• Incorrectly Calibrated Steering Angle Sensor
• Faulty Instrument Cluster
• Issues with the CAN Bus Communication
• Faulty ABS Module

Common Troubleshooting Steps

When dealing with the OBD-II code U2128, which indicates “Lost Communication with the Steering Angle Sensor,” there are several common troubleshooting steps you can follow to diagnose and potentially resolve the issue. Here’s a structured approach:

• Check for Other Codes: Use an OBD-II scanner to check for any additional trouble codes. Sometimes, multiple codes can provide more context for the issue.
• Inspect Wiring and Connectors: **Visual Inspection: Check the wiring harness and connectors associated with the steering angle sensor for any signs of damage, corrosion, or loose connections.
• **Connector Pins: Ensure that the pins in the connectors are not bent, corroded, or pushed back.
• Test the Steering Angle Sensor: **Sensor Functionality: If possible, test the steering angle sensor using a multimeter or scan tool to ensure it is functioning correctly. Check for proper voltage and resistance values as specified by the manufacturer.
• **Calibration: Some vehicles require the steering angle sensor to be calibrated after installation or repair. Refer to the vehicle’s service manual for calibration procedures.
• Check for Power and Ground: Verify that the steering angle sensor is receiving the correct voltage and has a good ground connection. Use a multimeter to check for power at the sensor connector.
• Inspect the CAN Bus: Since the steering angle sensor communicates over the CAN (Controller Area Network) bus, check for any issues with the CAN wiring or other modules on the bus.
• Look for shorts, opens, or high resistance in the CAN lines.
• Scan for Module Communication Issues: Use a scan tool to check if other modules (like the ABS, ESC, or airbag modules) are communicating properly. If other modules are also having communication issues, it may indicate a broader problem with the vehicle’s network.
• Check for Software Updates: Sometimes, software glitches can cause communication issues. Check if there are any available updates for the vehicle’s ECU or modules that may address the problem.
• Inspect for Physical Damage: Look for any signs of physical damage to the steering column, steering rack, or any components that may affect the steering angle sensor.
• Clear Codes and Test Drive: After performing the above checks and repairs, clear the trouble codes and take the vehicle for a test drive to see if the code returns.
• Consult Service Manual: If the issue persists, consult the vehicle’s service manual for specific diagnostic procedures related to the steering angle sensor and communication issues.1
• Seek Professional Help: If you are unable to resolve the issue after these steps, it may be best to consult a professional mechanic or technician who has experience with your specific vehicle make and model. By following these steps, you should be able to identify the root cause of the U2128 code and take appropriate action to resolve the communication issue with the steering angle sensor.