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Checking Lambda control after catalytic converter > < Checking Lambda probe and Lambda control after catalytic converter

A3 Mk1

Test sequence
Test sequence
  Note
t  No leaks in exhaust system.
t  Coolant temperature at least 80 °C.
–  Connect up the vehicle diagnostic and service information system -VAS 5052- and select the engine electronics control unit. Engine must be idling.
–  Select the function “Start basic setting”.
–  Select “Display group number 030”.
–  Check the specification in display zone 2.
  Note
t  The specifications are attained more quickly if the engine speed is increased.
t  The “Lambda probe status” indicates the status of the lambda control and the Lambda probes.
   
 Display zones
 1234
Display group 030: Lambda probe status at idling speed
DisplayX X XX X X  
DisplayLambda probe status bank 1, probe 1Lambda probe status
bank 1, probe 2		  
Operating range0 = off
1 = on		 0 = off
1 = on		  
Specification1 1 11 1 0  
NoteIf the reading does not match the specification → Chapter

   
Explanatory notes on 3-position displays in display group 030
XXXDisplay zones 1 and 2
  XLambda control: 0 = not active; 1 = active
 X Lambda probe condition: 0 = not active; 1 = active
X  Lambda probe heating condition: 0 = not active; 1 = active

  Note
t  The first position of the 3-position display (heating) fluctuates between 0 and 1.
t  Lambda control of the Lambda probe downstream of the catalytic converter (-B1--S2-) is not active without engine load.
–  Do not continue with testing until the display in zone 2 has attained “110” at least once.
   

Checking Lambda control after catalytic converter > < Checking Lambda probe and Lambda control after catalytic converter