Exhaust Pressure Regulator: Testing and Inspection

Exhaust Flap, Checking

Special tools, testers and auxiliary items required

• Vehicle Diagnostic, Testing, and Information System (VAS 5051B)

Procedure

- Let engine run briefly so that the required vacuum for the test is present in vacuum reservoir.

- Switch engine off.

- Connect the Vehicle Diagnostic, Testing, and Information System (VAS 5051B), switch on the ignition and select Vehicle Self-Diagnosis - 1 -.





- Select the following menu points in On Board Diagnostic:

• "01- Engine electronics"

• "Output Diagnostic Test Mode"

- Tap the -> button until Left Front/Right Rear Electronic Differential Lock Intake Valve (N321) - arrow - at left in luggage compartment is activated.





• 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. Refer to => [ Exhaust Flap Vacuum Diaphragm, Checking ] Testing and Inspection.

- Check vacuum line to vacuum reservoir and to Exhaust Flap Valve 1 (N321) under left side trim in luggage compartment.

- Check Left Front/Right Rear Electronic Differential Lock Intake Valve (N321) and using "Guided Fault Finding ".

- Complete On Board Diagnostic.

- Switch off ignition.