Page 14 of 63
24-88
 Evaluation display group 032  Display field: 
1 / 3 or 2 / 4  
Possible cause  
Corrective action  
Oxygen sensor 
adaptation value in range: 
10.0 to 25.0 %   
False air in intake area- Check intake system for leaks and repair false 
air. 
 Page 24
-64
 . 
  
 
Fuel pressure too low- Check fuel pressure regulator   Page 24
-30
  
 
Mass Air Flow (MAF) sensor faulty- Mass Air Flow (MAF) sensor, checking 
 
 Page 24
-56
 
  
 
Oxygen sensor heating faulty
 Oxygen sensor faulty- Check oxygen sensor heating   Page 24
-116
  
 
Fuel injector does not open or opens 
only partially - Check fuel injectors   Page 24
-36
  
 
Evaporative Emission (EVAP) Canister 
Purge Regulator Valve sticks - Check Evaporative Emission (EVAP) Canister 
Purge Regulator Valve   Page 24
-128
 
  
 
Ignition coil or spark plug faulty- Check ignition coils   Page 28
-7
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        Page 15 of 63
24-89
      
Checking primary voltage  
      Component location of harness connectors   
Overview of component locations, page   Page 
24
-5   
     
Note:  
     Coolant reservoir screws must be removed and 
coolant reservoir must be placed to side in order 
to access this harness connector. The coolant 
hoses can remain connected. 
     
Test requirement:  
     
Fuse for oxygen sensor are OK 
     
-  Disconnect 4-pin harness connector leading to 
respective oxygen sensor. 
    
If specified value is not obtained:  -  Connect multimeter between terminal 3 and 4 for voltage 
measurement. 
-  Switch ignition on.
 
Specification: 0.400 to 0.500 V
-  Switch ignition off.
- 
Check oxygen sensor wires   Bank 1, page   Page 24
-90
 or   Bank Pa
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        Page 43 of 63
24-111
      
Checking primary voltage  
      Component location of harness connectors   
Overview of component locations - page   Page 
24
-5   
     
-  Disconnect 4-pin harness connector leading to 
respective oxygen sensor. 
    
If specified value is not obtained:  
If specified value is obtained:  -  Connect multimeter between terminal 3 and 4 for voltage 
measurement. 
-  Switch ignition on.
 
Specification: 0.400 to 0.500 V
-  Switch ignition off.
-  Check oxygen sensor wires   Bank 1 page   Page 24
-112
 or bank 2 
page  Page 24
-114
 . 
-  Replace appropriate oxygen sensor behind catalytic converter.
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        Page 59 of 63
24-123
       If there is no voltage again:  
     
-  Check wire connection from terminal 1 to Fuel 
Pump (FP) relay via fuse for open circuit. 
     
       Electrical Wiring Diagrams, Troubleshooting & 
Component Locations binder         If voltage supply is OK:  
    
If there is no voltage:  -  Connect multimeter for voltage measurement as follows:Harness connector  
Terminal  
Measure 
to  
2 (Ground -GND- activation of Engine Control Module -
ECM-)  B+  
- Start engine.
 
Specification: approx. battery voltage, possibly fluctuating
-  Switch ignition off.
-  Connect VAG1598/31 test box at wiring harness to ECM, do not 
connect ECM   Page 24
-17
 . 
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