Page 41 of 61
24-113
      
Continuation  
      If the specified value in display group 037 and 
038, display 3 or 4 is not obtained:  
     
-  Check exhaust system and catalytic converter 
for leaks (check clamps and exhaust for 
damage) 
     
-  If the difference of the values in measuring 
blocks, display fields 3 (oxygen sensor 
correction value) is to large (e.g.:+500 ms, -500 
ms), it is possible that the oxygen sensor are 
interchanged (mixed up). 
      If none of the causes are identified:  
     
-  Replace particular oxygen sensor "before" 
catalytic converter. 
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        Page 42 of 61
24-114
      
Oxygen sensor heater for oxygen 
sensor, checking
 
     
Note:  
     The oxygen sensor heating circuit is monitored 
by the On Board Diagnostic (OBD). Check DTC 
memory  Page 01-15
 . 
     
-  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  
-  Press buttons -0- and -8- to select function "Read Measuring Value 
Block" and confirm entry with -Q- button. 
Read Measurin
g Value Block 
Input display group number XXX
    
Indicated on display  
-  Press buttons -0-, -4- and -1- to select "display group number 041" and 
confirm entry with -Q- button. 
Read Measuring Value Block 41  
1 
2 
3 
4
    
Indicated on display  
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        Page 43 of 61
24-115
      
-  Adjust engine speed to approx: 3000 RPM
     
-  Check resistance of oxygen sensor heater.
  
Display fields  
  
1   2   3   4  
Display Group 041: Oxygen sensor heater, Bank 1 (at idle speed)  
Display  
xxx kOhm  
Htg.bC.ON  
xxx kOhm  
Htg.aC.ON  
Indicates  
Bank 1, Sensor 1  
Status of 
heater  Bank 1, Sensor 2  
Status of 
heater  
Range    
  Htg.bC.ON  
Htg.bC.OFF    
Htg.aC.ON  
Htg.aC.OFF  
Specified 
value  0 - 0.5 kOhm  
Htg.bC.ON/OFF  
0 - 0.5 kOhm  
Htg.aC.ON/OFF  
Note  
It can take a few minutes until 
specification are obtained    
It can take a few minutes until 
specified values are obtained         
- Press -C- button.
     
-  Press buttons -0-, -4- and -2- to select "display 
group number 042" and confirm entry with -Q- 
button. 
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        Page 44 of 61
24-116
 
  
Display fields  
  
1   2   3   4  
Display Group 042: Oxygen sensor heater, Bank 2 (at idle speed)  
Display  
xxx kOhm  
Htg.bC.ON  
xxx kOhm  
Htg.aC.ON  
Indicates  
Bank 2, Sensor 1  
Status of 
heater  Bank 2, Sensor 2  
Status of 
heater  
Range    
  Htg.bC.ON  
Htg.bC.OFF    
Htg.aC.ON  
Htg.aC.OFF  
Specified 
value  0 - 0.5 kOhm  
Htg.bC.ON/OFF  
0 - 0.5 kOhm  
Htg.aC.ON/OFF  
Note  
It can take a few minutes until 
specifications are obtained    
It can take a few minutes until 
specifications are obtained          If the specification is not attained:  
     
-  Check voltage supply for oxygen sensor heater 
 Page 24
-117
 . 
     
-  Check oxygen sensor signal wire and activation 
 Page 24
-122
 . 
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        Page 49 of 61
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       If the wiring is OK but the oxygen sensor heater 
still has no Ground (GND) connection:  
     
-  Replace particular oxygen sensor.
     
-  Display readiness code   Page 01
-101
 . The 
readiness code must be generated if the DTC 
memory was erased   Page 01
-105
 . 
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        Page 50 of 61
24-122
      
Oxygen sensor signal wire and 
activation, checking
 
     
Note:  
     The oxygen sensor signal is monitored by the 
OBD system. 
     
-  Check DTC memory   Page 01
-15
 .
     
-  If a oxygen sensor malfunction is displayed and 
the oxygen sensor heater is OK, disconnect 
harness connector for relevant oxygen sensor. 
      Component location of 4-pin harness connector 
of oxygen sensor   Page 24
-5 .  
    
If the Specified value is not obtained, check oxygen sensor wiring:  -  Test voltage by connecting hand-held multimeter Fluke 83 (or 
equivalent) (measuring range 2 V) between sockets 3 and 4 of 
connector on wiring harness. 
- 
Switch ignition on. Specified value: 450   50 mV.   Bank 1, Sensor 1   Page 24
-123
 .
   Bank 1, Sensor 2   Page 24
-125
 .
   Bank 2, Sensor 1   Page 24
-127
 .
   Bank 2, Sensor 2   Page 24
-129
 .
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        Page 59 of 61
24-131
       If no malfunction can be identified in the wiring:  
     
-  Replace Motronic Engine Control Module (ECM) 
-J220  Page 24
-24
 . 
     
-  Display readiness code   Page 01
-101
 . The 
readiness code must be generated if the DTC 
memory was erased   Page 01
-105
 . 
Pa
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play?action=Goto&t
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pair&id=AUDI.B5.FU04.24.2