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.
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Page 19 of 166
01-16
No DTC reco
gnized
Indicated on display
or -
Press button.
X DTC reco
gnized
Indicated on display
The stored malfunctions will be displayed and printed out in sequence.
Note: - Locate and eliminate printed out malfunctions according to DTC table
Page 01
-19
.
If no malfunction is stored in the DTC memory, do not erase memory,
otherwise readiness code must be generated. If the DTC memory was erased, generate readiness code Page 01
-
105
.
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Page 20 of 166
01-17
-
Press button.Rapid data transfer
HELP
Select function XX
Indicated on display:
Notes: - Press buttons -0- and -5- to select function "DTC Memory" and confirm
entry with -Q- button.
Attention!DTC memor
y was not checked
Indicated on display:
Test sequence has not been followed.
- Check DTC memory.
Under the following conditions the DTC memory will not be erased:
If Ignition was switched off after DTC memory has been checked.A static malfunction has not been eliminated.
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Page 21 of 166
01-18
Rapid data transfer DTC Memor
y is erased!
Indicated on display:
Note:
During testing and repair work, malfunctions can be recognized from other
control modules (e.g. disconnected harness connectors). Therefore on
completion, the DTC memories of all control modules must be checked
and erased.
End output -
Press button.- After repairs, check DTC memory again.
Rapid data transfer
HELP
Select function XX
Indicated on display:
- Press buttons -0- and -6- to select function "End Output" and confirm
entry with -Q- button.
Rapid data transfer
HELP
Insert address word XX
Indicated on display:
- Switch ignition off and disconnect diagnostic connector.
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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
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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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Page 31 of 166

01-27
DTC
Description of malfunction
Corrective action
SAE
VAG
P0300 16684 Random/Multiple Cylinder
Misfire Detected
2) - Check cause for misfire Page 28
-52
P0301 16685
Cyl.1 Misfire Detected
2)
- Check fuel tank level
P0302 16686
Cyl.2 Misfire Detected 2)
P0303 16687
Cyl.3 Misfire Detected 2)
P0304 16688
Cyl.4 Misfire Detected 2)
P0305 16689
Cyl.5 Misfire Detected 2)
P0306 16690
Cyl.6 Misfire Detected 2)
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 .
The Malfunction Indicator Light (MIL) will blink if the Engine Control Module (ECM) recognizes misfire that could damage the
catalytic converters.
Notes:
On malfunction which could be caused by lack of fuel (e.g.: misfire) the malfunction P1250 "Fuel level too low" will be
displayed in addition. That means, the misfiring was detected due to lack of fuel in the tank and not due to a technical
malfunction.
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Page 35 of 166

01-29
DTC
Description of
malfunction
Corrective action
SAE
VAG
P0421 16805 Warm Up Catalyst,
Bank 1
Efficiency Below
Threshold
2) Repair Manual, 2.7 Liter V6 5V BiTurbo Engine Mechanical, Repair Group 26;
Components of Exhaust system removing and installing, Catalytic converter
removing and installing - Generate readiness code Page 01
-99
, if same DTC is displayed again, replace
warm up catalytic converter bank 1
P0431 16815 Warm Up Catalyst,
Bank 2
Efficiency Below
Threshold
2) Repair Manual, 2.7 Liter V6 5V BiTurbo Engine Mechanical, Repair Group 26;
Components of Exhaust system removing and installing, Catalytic converter
removing and installing - Generate readiness code Page 01
-99
, if same DTC is displayed again, replace
warm up catalytic converter bank 1
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 .
Important note:
The warm up catalytic converters are located between the two oxygen sensors of the relevant cylinder bank. The warm up
catalytic converters (little smaller than main catalytic converter) are located closer to the engine, not to be misunderstood with
the main catalysts you see immediately once the vehicle is lifted.
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