Page 10 of 166
01-8
 
 Mode 5 displays the static dimensions of the oxygen sensors, which are legally required. Since these dimensions are not 
directly relevant to oxygen sensor diagnostics, mode 5 is insignificant for the authorized Audi center. 
 With mode 6 all measured values can be checked from components and systems that are not constantly monitored.
 Using mode 7, DTCs can be checked for which the Malfunction Indicator Light (MIL) is not yet lit (MIL is not on, no DTCs 
under mode 3). 
 Under mode 8 the tank leak test will be checked.
 With mode 9 the following vehicle information can be read out: Vehicle Identification Number (VIN), Part number and 
program/data level of the engine control module and the check sum (this value is a internal calculated value). 
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        Page 11 of 166
01-9
      
Vehicle diagnostic, testing and 
information system VAS5051 or 
VAG1551, connecting and selecting 
functions
 
     
Requirements  
     
Fuses for engine electronics OK 
     Fuel pump relay OK 
     Battery voltage at least 11 V 
     Ground (GND) connection for engine and 
transmission OK 
     
-  Switch ignition off.
    
Note:  
The Data Link Connector (DLC) is located below the dash, to the left of 
the steering column.  -  Connect vehicle diagnostic, testing and information system VAS5051 
with VAS5051/1 diagnostic cable. As an alternative, connect VAG1551 
scan tool with VAG1551/3B diagnostic cable. 
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        Page 13 of 166
01-11
      
-  If no display appears, check diagnostic 
cables: 
     
       Electrical Wiring Diagrams, Troubleshooting & 
Component Locations         Depending on the function required:  
     
-  Switch ignition on.
     
   or
     
   Start engine   Page 01
-6 , table of available 
functions. 
     
-  Switch on printer with PRINT button (indicator 
light in button lights up). 
     
-  Press button -1- to select "Rapid data transfer" 
operating mode. Rapid data transfer 
HELP
Insert address word XX
    
Indicated on display:  
Rapid data transfer 
Q
01 - En
gine Electronics
    
-  Press buttons -0- and -1- to insert "Engine electronics" address word 
01. 
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        Page 16 of 166
01-13
      
Control module identification (example)  4D0907551.. 2.7L V6/5VT 
G 0002..
Codin
g 06711 
WSC 06388
    
The display on VAG1551 will show the control module identification, for 
example:  1) 
The engine is a so called Biturbo engine, that means the engine is 
equipped with two turbo chargers. "Bi" (latin) stand for two.  4D0907551...   Engine Control Module (ECM) Part No.  
2.7 L   Engine displacement  
V6 / 5VT   Engine configuration  
(V6 5-valve Turbo
1)  
  
G or no 
display "G" for vehicles with Cruise control system or not  0002ECM Software version  Coding 
06711 Coding of ECM  WSC 06388Dealership code of VAG1551 with which the last 
coding was performed  
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        Page 17 of 166
01-14
       If the coding differs from the vehicle version, 
then:  
     
-  Check coding of engine control module   Page 
01
-93
 , Coding engine control module. 
     
- 
Press button.Rapid data transfer 
HELP
Select function XX
    
Indicated on display:  
Note:  
After pressing the HELP button, an overview of the possible functions is 
printed out. 
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        Page 18 of 166
01-15
      
Diagnostic Trouble Code (DTC) Memory, 
checking and erasing
 
     
-  Connect vehicle diagnostic, testing and 
information system VAS5051 or VAG1551 scan 
tool and select "Engine Electronics" by entering 
address word 01   Page 01
-9. When doing this 
the engine must be idling. 
      Only if engine does not start:  
     
-  Check engine with ignition switched on.
     
-  Switch on printer with PRINT button (indicator 
light in button lights up). Rapid data transfer 
HELP
Select function XX
    
Indicated on display  
-  Operate scan tool according to information on display:
-  Press buttons -0- and -2- to select function "Check DTC Memory" and 
confirm entry with -Q- button. 
Pa
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        Page 22 of 166

01-19
 Diagnostic Trouble Code (DTC) table
 
Notes:  
 
If malfunctions occur in the sensors and components being monitored, they will be stored in the DTC memory together 
with an indication of the type of malfunction. Notes on Engine Power Control (EPC) (drive by wire)   Page 24
-139
 . 
 Malfunctions relating to the electronic throttle are also indicated by the EPC (Electronic Power Control) warning light in the 
instrument cluster. 
 Malfunction which decrease exhaust emissions are indicated by an Exhaust Malfunction Indicator Light (MIL), the MIL is 
located in the instrument cluster. As soon as certain malfunction are recognized, the MIL is switched on immediately. 
There are also malfunctions, were the MIL is switched on only after the engine is started again. 
 Sporadically occurring malfunctions (temporary malfunctions) will be indicated on the VAG1551 display as "SP."
 The DTC table is arranged according to the 5-digit DTC in the left-hand column.
 If a malfunction is stored in the DTC memory and then does not occur again during the next 40 engine warm-up phases, 
the DTC will be automatically erased. 
 Components that are indicated as being faulty by the VAG1551 should not be replaced immediately. Always start by 
checking the wiring, connectors and Ground (GND) connections for the component using the current wiring diagram. This 
is particularly important in the case of sporadic malfunctions (indicated by the letters "SP"on the scan tool display). 
 If the connector for the engine control module is disconnected or if the battery is disconnected, all the learned values 
(adaptation values) stored in the control module will be erased, although the contents of the DTC memory will remain 
intact. The next time the engine is started the idling may be rough at first. In this case let the engine run at idle for a few 
Pa
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        Page 24 of 166

01-20
 
DTC  
Description of malfunction  
Corrective action  
SAE  
VAG  
  
  
P0101   16485   Mass Air Flow (MAF) sensor -
G70-  
Implausible signal  - Check Mass Air Flow (MAF) sensor   Page 24
-59
P0102   16486   Mass or Volume Air Flow 
Circuit  
Low input 
2)  - Check Mass Air Flow (MAF) sensor -G70   Page 24
-59
P0103   16487   Mass or Volume Air Flow 
Circuit  
High Input
 2)
    
P0106   16490   Manifold Abs.Pressure or 
Bar. Pressure  
Range/Performance 
2) 4)
   Repair Manual, 2.7 Liter V6 5V BiTurbo Engine Mechanical, Repair 
Group 21; Turbocharger; Checking Charge Air Pressure Sensor -G31   
2) With this malfunction the exhaust Malfunction Indicator Light (MIL) is only switched on by the ECM, if the malfunction is 
recognized after the engine has been restarted. Significance of MIL   Page 01
-3 .  
4) Absolute manifold pressure will be determined by the Charge Air Pressure Sensor -G31 (instead of displayed -G71), the air 
pressure is determined by the Barometric Pressure (BARO) Sensor -F96 (in Engine Control Module (ECM))  
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