B3A51

Symptoms

• Aerodynamic element C does not change position
• Active aerodynamics system malfunction indicator is on
• Minor change in fuel consumption
• The general body system malfunction indicator is on
• Error code persists after reset

Causes

• Broken position sensor power wire
• Signal wire short circuit to ground
• Malfunction of the position sensor itself
• Oxidation of the sensor connector
• Aerodynamics control module malfunction

How to Fix

1. Read error codes and check position sensor data in real time
2. Check the sensor supply voltage (usually 5V from the module)
3. Measure the signal voltage of the sensor at different positions of the element
4. Inspect the sensor connector and wiring harness for damage.
5. Replace the position sensor if the fault is confirmed
6. Reset codes and check system operation

Related codes

Error B3A51 by Vehicle Brand