Page 4 of 61
24-82
      
Notes:  
     
For the defined troubleshooting procedure, it is 
possible to switch off the oxygen sensor control 
by selecting Display Group 99 in "Basic Setting" 
mode and to switch it on again by selecting 
Display Group 99 in "Read Measuring Value 
Block" mode. 
     After selecting Display Group 99 (either in 
"Basic Setting" mode or in "Read Measuring 
Value Block" mode) it is possible to switch back 
and forth between function 04 ("Basic Setting") 
and function 08 "Read Measuring Value Block") 
by pressing buttons 4 and 8 on VAG1551 scan 
tool. 
     When exiting the "Basic Setting" mode (function 
04) the oxygen sensor control is automatically 
switched on again. 
     
Test conditions  
     Perform road test and do not erase DTC 
memory. 
     Coolant temperature at least 85 C (Display 
group 004, display field 3) 
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        Page 5 of 61

24-83
      
Checking function  
     
-  Connect vehicle diagnostic, testing and 
information system VAS5051 or VAG1551 scan 
tool and select engine electronics control 
module by entering address word "01"   Page 
01
-9 . When doing this the engine must be at 
idle. 
Rapid data transfer 
HELP
Select function XX
    
Indicated on display  
Note:  
During the basic setting the Evaporative Emission (EVAP) canister purge 
regulator valve -N80 is closed and the A/C compressor is switched off.  -  Press buttons -0- and -4- to select function "Basic Setting" and confirm 
entry with -Q- button. 
Basic Settin
g 
Input displa
y group number XXX
    
Indicated on display  
-  Press buttons -0-, -3- and -0- to select "display group number 030" and 
confirm entry with -Q- button. 
System in Basic Setting 30  
1 
2 
3 
4
    
Indicated on display: (1 - 4   display fields)  -  Check oxygen sensor status in display fields 1 to 4.
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        Page 8 of 61
24-86
      
Checking oxygen sensor adaptation and 
oxygen sensor control  
     
-  Connect vehicle diagnostic, testing and 
information system VAS5051 or VAG1551 and 
select engine electronics control module by 
entering address word "01"   Page 01
-9. When 
doing this the engine must be idling. 
Rapid data transfer 
HELP
Select function XX
    
Indicated on display  
Note:  
During the basic setting the Evaporative Emission (EVAP) canister purge 
regulator valve -N80 is closed and the A/C compressor is switched off.  -  Press buttons -0- and -4- to select function "Basic Setting" and confirm 
entry with -Q- button. 
Basic Settin
g 
Input displa
y group number XXX
    
Indicated on display  
-  Press buttons -0-, -3- and -3- to select Display Group 33 and confirm 
entry with -Q- button. 
System in Basic Setting 33  
1 
2 
3 
4
    
Indicated on display: (1 - 4   display fields)  
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        Page 9 of 61

24-87
      
-  Check oxygen sensor control in display fields 1 
to 4: 
  
Display fields  
  
1  2  3  4  
Display Group 33: Oxygen sensor control at idle speed  
Display  
xx.x %  
xx.x V  
xx.x %  
xx.x V  
Indicates  
Oxygen sensor control, 
bank 1  Oxygen sensor voltage, 
bank 1  Oxygen sensor control, 
bank 2  Oxygen sensor voltage, 
bank 2  
Work range  
min.: -25.0 %  
max.: 25.0 %  min.: 0.000 Volt  
max.: 1.000 Volt  min.: -25.0 %  
max.: 25.0 %  min.: 0.000 Volt  
max.: 1.000 Volt  
Specification  
-4.0 to 4.0 %  
(The value must 
fluctuate by 2 %)  Between 0.000 and 
1.000 V the voltage 
should fluctuate  -4.0 to 4.0 %  
(The value must 
fluctuate by 2 %)  Between 0.000 and 
1.000 V the voltage 
should fluctuate  
Note  
If readout does not 
match specification   
Page 24
-89
   
If readout does not 
match specification   
Page 24
-92
   
If readout does not 
match specification   
Page 24
-89
   
If readout does not 
match specification   
Page 24
-92
   
     
-  Press button -C-.
     
-  Press buttons -0-, -3- and -3- to select "display 
group number 033" and confirm entry with -Q- 
button. 
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        Page 16 of 61
24-94
 
Rapid data transfer  
HELP
Select function XX
    
Indicated on display  
-  Press buttons -0- and -4- to select "Basic Setting" and confirm with -Q- 
button. 
Basic Setting 
Q
Input displa
y group number XXX
    
Indicated on display  
Test requirements   -  Press -0-, -3- and -4- to select "display group number 034" and confirm 
with -Q- button. 
Engine runs at 1900 - 2200 RPM 
System in Basic Setting 34  
1 
2 
3 
4
    
Indicated on display  
-  Continue test as soon as display field 4 indicates "Test ON".
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        Page 19 of 61
24-96
      
Continuation  
      If specified value in display field 3 or 4 is not 
obtained:  
     
-  Replace Heated Oxygen Sensor (HO2S) before 
Three Way Catalytic Converter Bank 1 -G39. 
     
Test sequence for oxygen sensor 1 before 
catalytic converter bank 2  
     
-  Connect vehicle diagnostic, testing and 
information system VAS5051 or VAG1551 and 
select engine electronics control module by 
entering address word "01"   Page 01
-9. When 
doing this the engine must be at idle. 
Rapid data transfer  
HELP
Select function XX
    
Indicated on display  
-  Press buttons -0- and -4- to select "Basic Setting" and confirm with -Q- 
button. 
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        Page 25 of 61

24-102
      
Test conditions  
     
Perform road test and do not erase DTC 
memory. 
     Coolant temperature at least 85 C (185 F) 
(Display group 004, display field 3) 
     
-  Connect vehicle diagnostic, testing and 
information system VAS5051 or VAG1551 scan 
tool and select engine electronics control 
module by entering address word "01"   Page 
01
-9 . When doing this the engine must be at 
idle. 
Rapid data transfer 
HELP
Select function XX
    
Indicated on display  
Note:  
During the basic setting the Evaporative Emission (EVAP) canister purge 
regulator valve -N80 is closed and the A/C compressor is switched off.  -  Press buttons -0- and -4- to select function "Basic Setting" and confirm 
entry with -Q- button. 
Basic Settin
g 
Input displa
y group number XXX
    
Indicated on display  
-  Press buttons -0-, -3- and -4- to select "display group number 034" and 
confirm entry with -Q- button. 
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        Page 26 of 61
24-103
 
System in Basic Setting 34  
1 
2 
3 
4
    
When indicated on display:  
Note:  
This process can take a few minutes.  -  Adjust engine speed using VAG1788/10 to 2800 - 3200 RPM.
-  Continue test as soon as display field 2 indicates an exhaust 
temperature of more than 320  C. - Press -C- button.
-  Adjust engine speed using VAG1788/10 to 1900 - 2200 RPM.
Basic Settin
g 
Q
Input displa
y group number XXX
    
When indicated on display:  
-  Press buttons -0-, -3- and -0- to select "display group number 030" and 
press -Q- button to confirm input. 
System in Basic Setting 30  
1 
2 
3 
4 
    
When indicated on display:  
Note:  
"Oxygen sensor status" indicates status of oxygen sensor control and 
oxygen sensor.  -  Check oxygen sensor status for oxygen sensor behind catalytic 
converter in display field 2. 
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