Exhaust flap, checking

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Special tools, testers and auxiliary items required

Fig 1: Identifying Vehicle Diagnosis, Testing And Information System VAS 5051B

Courtesy of VOLKSWAGEN UNITED STATES, INC.

Vehicle diagnostic, testing, and information system VAS 5051B

Test sequence

Let engine run briefly so that the required vacuum for the test is present in vacuum reservoir.
Switch engine off and connect Vehicle Diagnosis, Testing and Information System VAS 5051B.
Switch ignition on.
Press Vehicle Self-Diagnosis button, select vehicle system "01 - Engine electronics" and activate with → button.

Fig 2: Diagnostic System VAS 5051: Display

Courtesy of VOLKSWAGEN UNITED STATES, INC.

Display on VAS 5051B :

In selection - 1 - , press "011 - Measured values" and activate by pressing → button.
Press → button repeatedly until Exhaust Flap Valve 1 N321 is activated.

Fig 3: Generating Vacuum Using Hand Vacuum Pump

Courtesy of VOLKSWAGEN UNITED STATES, INC.

Operating rod - arrow - for exhaust flap must move back and forth at both rear mufflers.

If actuator rod does not move:

Check exhaust flap vacuum reservoir → Exhaust flap vacuum reservoir, checking .
Check vacuum line to vacuum reservoir and to Exhaust Flap Valve 1 N321 under left side trim in luggage compartment.
Check Exhaust Flap Valve 1 N321 in "Guided Fault Finding" operating mode.
End function "03 - Output Diagnostic Test Mode (DTM)" by pressing ← button.

Press "06 - End Output".
Switch off ignition.