Air mass system test M47TÜ/M57TÜ

Instructions for function test

To ensure that the air mass system test provides a meaningful result, the test prerequisites listed below must be met without fail.

Preconditions for the test:

• The engine must be at operating temperature.
  
• All auxiliary loads such as rear window heating or air conditioning system, must be switched off.
  
• No electrical faults in the following systems may be stored in the DDE fault memory:
  
  • Charge-air-pressure control
    
  • Exhaust-gas recirculation
    
  • Air-mass flow sensor
    
  • Turbo pressure sensor
    
  • Intake-air temperature sensor
    
  • Charge-air temperature sensor
    
  • Atmospheric pressure sensor
    
• Intake-air duct and exhaust system must be OK.