Checking the Turbocharger Control Valve Control

CHECKING THE TURBOCHARGER CONTROL VALVE CONTROL

Condition

- Diagnostic Trouble Codes (DTCs) in Motronic 4.4 absent.
- Diagnostic trouble codes (DTCs) in AW 50-42 absent.
- Engine at normal operating temperature.
- The fault is permanent.

Possible Source

- Defective Turbocharger (TC).





Checking the Turbocharger Control Valve Control
- START engine.
- Go into scrolling values.
- Accelerate hard several times and watch parameter "TC CONTROL".

Does the parameter constantly exceed approx. 90%?

Yes:
- Proceed to test step below.

No:
- Check signals, See: Breakout Box and Parameter Tables
- If there are no faults, Proceed to Checking Three-Way Catalytic Converter and Exhaust System section.





Checking the Turbocharger Control Valve and its Hoses

- Ignition OFF.
- Check that the hose between the turbocharger (TC) control valve and fresh air intake are undamaged and free from blockage.
- Check that the nipples on the turbocharger (TC) control valve and fresh air intake are not blocked.

Are the hose and nipples OK?

Yes:
- Proceed to Checking Three-Way Catalytic Converter and Exhaust System section.

No:
- Replace components as necessary.
- Then proceed to Verification section below.





Verification

- START engine.
- Go into scrolling values.
- Accelerate hard several times and watch parameter "TC CONTROL".

Does the parameter constantly exceed approx. 90%?

Yes:
- Proceed to test step below.

No:
- Fault corrected.

Fault-Tracing Information

- The fault should now have been diagnosed and corrected.
- Since this is not the case the fault-tracing has failed.
- Do you want to exit fault-tracing?

Yes:
- Fault not corrected.

No:
- Return to Checking the Turbocharger Control Valve and its Hoses section above.