Warning Z1 Air inlet sensor TL2 open circuit — Air sensor connection issue

What does 5408 mean?

This warning appears if the air inlet sensor TL2 or its signal cable is broken. It triggers after 3 errors related to this sensor within 2 hours.

• Broken air inlet sensor TL2 or its signal cable.
• Loose screw terminal on the I/O module for sensor TL2.
• Defective I/O module.

Click steps to track your progress.

1. 1

   With the sensor disconnected from the I/O module, measure the resistance of the sensor and signal cable.

2. 2

   Check that the screw terminal on the I/O module for sensor TL2 is properly tightened.

3. 3

   If the sensor and connections seem fine, consider replacing the I/O module.