Page 29 of 37
21-24
       If LED does not light:  
     
-  Check wire connection from terminal 1 to Fuel 
Pump (FP) relay via fuse for open circuit. 
     
       Electrical Wiring Diagrams, Troubleshooting & 
Component Locations        
-  Repair open circuit if necessary.
      If wire connection is OK:  
     
-  Check Fuel Pump (FP) relay.
     
       Repair Manual, 2.7 Liter V6 5V BiTurbo Fuel 
Injection & Ignition, Engine Code(s): APB, Repair Group 24
   
      If LED lights:  
     
- Check activation,   Page 21
-25
 .
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        Page 30 of 37
21-25
      
Checking activation  
    
 Repair Manual, 2.7 Liter V6 5V BiTurbo Fuel Injection & Ignition, 
Engine Code(s): APB, Repair Group 01
   
If LED does not blink or if it remains constantly lit:  
 Repair Manual, 2.7 Liter V6 5V BiTurbo Fuel Injection & Ignition, 
Engine Code(s): APB, Repair Group 24
    -  Connect VAG 1527B voltage tester to connector terminals 1 (B+) and 
2. 
-  Initiate output Diagnostic Test Mode (DTM) and activate recirculating 
valve for turbocharger -N249-. 
 
LED must blink.
-  Connect VAG 1598/31 test box at wiring harness to ECM. Do not 
connect ECM. 
    
-  Check the following wire connections for open circuit and short circuit 
to Ground (GND) and B+: Harness connector terminal  
VAG 1598/31 test box  
Bushing  
2   9  
-  Repair open circuit or short circuit if necessary.
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        Page 31 of 37
21-26
       If wire connection is OK:  
     
-  Replace Engine Control Module (ECM).
     
       Repair Manual, 2.7 Liter V6 5V BiTurbo Fuel 
Injection & Ignition, Engine Code(s): APB, Repair Group 24
   
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        Page 33 of 37
21-28
      
Note:  
     The charge air pressure sensor -G31- and wire 
connections are monitored by the Engine Control 
Module (ECM). 
     
-  Connect VAS 5051 tester or VAG 1551 scan 
tool and select control module for engine 
electronics using "address word" 01. Engine 
must run at idle. 
     
       Repair Manual, 2.7 Liter V6 5V BiTurbo Fuel 
Injection & Ignition, Engine Code(s): APB, Repair Group 01
   
     
-  Check DTC memory of Engine Control Module 
(ECM). 
     
       Repair Manual, 2.7 Liter V6 5V BiTurbo Fuel 
Injection & Ignition, Engine Code(s): APB, Repair Group 01
   
      If a Diagnostic Trouble Code (DTC) relating to 
the charge air pressure sensor -G31- is 
indicated:  
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        Page 35 of 37
21-30
      
-  Connect VAG 1598/31 test box to wiring 
harness for Engine Control Module (ECM), also 
connect ECM -1-. 
     
       Repair Manual, 2.7 Liter V6 5V BiTurbo Fuel 
Injection & Ignition, Engine Code(s): APB, Repair Group 24
   
    
If the specified value is met:  -  Check the following wire connections for open circuit and short circuit 
to Ground (GND) and B+: Harness connector terminal  
VAG 1598/31 or test box  
Bushing  
1   108  
3   98  
-  Repair open circuit or short circuit if necessary.
-  Check signal wire,   Page 21
-31
 .
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