fuel AUDI A8 1995 D2 / 1.G AHA Engine On Board Diagnostic Workshop Manual

01-1


On Board Diagnostic (OBD)

Function

The Multiport Fuel Injection (MFI) system is
equipped with an Engine Control Module (ECM) -
J220- with On Board Diagnostic (OBD)
capability.
When malfunctions occur in sensors or
components monitored by OBD, Diagnostic
Trouble Codes (DTC) are stored in DTC
memory.
Stored DTCs are identified using the VAG1551
Scan Tool (ST) page 01
-16
.
After the necessary repairs are completed, DTC
memory must be erased page 01
-49
.
OBD II legal regulations require a display
(readiness code) that shows inspection
readiness for the annual exhaust emissions test.
The readiness code shows that every component
and/or system that affects exhaust emissions,
which can lead to the Malfunction Indicator Lamp
(MIL) being switched on, has been operated at
least once with positive results.
The readiness code is reset and/or erased and
must be regenerated every time DTC memory is
erased, the power supply to the ECM -J220- is
interrupted (example: when connecting
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Battery Positive Voltage (B+) OK (at least 11
volts)
Engine and transmission GND connections
OK Electrical Wiring Diagrams,
Troubleshooting & Component Locations
binder

Fuel pump relay OK
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01-11

Notes:
If the ECM version that corresponds to the
vehicle is not displayed, replace ECM page
01
-68
. Incorrect ECM coding leads to:

Performance problems (e.g. jerky shifting,
abrupt load changes, etc.)
Increased fuel consumption
Elevated exhaust gas values
Reduction in transmission service life
Storage of non-existent malfunctions in DTC
memory
Necessary functions not being carried out
(oxygen sensor control, actuation of EVAP
canister system, etc.)

-
Press button to advance through program
sequence.
Rapid data transfer
HELP
Select function XX

Indicated on display
- Continue as specified in procedures for specific OBD functions.
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01-13

4D0907551A 2.8L V6/5V MOTR HS D01 Coding 06051
WSC 00000

Indicated on display (ECM identification and coding, e.g. 06051)
-
Press button to advance through program sequence.
Rapid data transfer
HELP
Select function XX

Indicated on display
Notes:
The Motronic ECM -J220- only uses the code that has been entered after
the ignition has been switched off once. Incorrect coding leads to: - Press buttons -0- and -6- to select "End Output" function 06, and press
-Q- button to confirm input.
Performance problems (e.g. jerky shifting, abrupt load changes, etc.)Increased fuel consumptionElevated exhaust gas valuesStorage of non-existent malfunctions in DTC memoryReduction in transmission service life
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01-22

Diagnostic Trouble Code
(DTC)
Malfunction text
MIL
Corrective action
SAE
VAG



P0300 16684 Random/Multiple
Cylinder
Misfire Detected 2 Dcy /
blink - Fuel level too low, check fuel level and add if
necessary
- Check misfire detection page 28
-16
- Check fuel injectors page 24
-102
- Carry out output Diagnostic Test Mode (DTM)
page 01
-51

- Check engine speed (RPM) sensor -G28- page 24
-88

P0301 16685 Cyl. 1
Misfire Detected
P0302 16686 Cyl. 2
Misfire Detected
P0303 16687 Cyl. 3
Misfire Detected
P0304 16688 Cyl. 4
Misfire Detected
P0305 16689 Cyl. 5

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01-23

Diagnostic Trouble Code
(DTC)
Malfunction text
MIL
Corrective action
SAE
VAG



P0321 16705 Ign./Distributor Eng. Speed Inp. Circ.
Range/Performance 2 Dcy
- Check engine speed (RPM) sensor -
G28- page 24
-88

P0322 16706 Ign./Distributor Eng. Speed Inp. Circ.
No Signal Immed.
Note on misfire malfunctions:
For malfunctions that may be caused by low fuel volume (i.e. combustion misfire) a low-fuel malfunction (DTC "P1250") is also
stored when there is less than 2 gallons of fuel remaining in the tank.
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01-25

Diagnostic Trouble
Code (DTC)
Malfunction text
MIL
Corrective action
SAE
VAG



P0432 16816 Main Catalyst, Bank2
Efficiency Below Threshold 2
Dcy - Check HO2S -G108- and O2S control (bank 2, sensor 1)
page 24
-22

P0441 16825 EVAP Emission Contr. Sys.
Incorrect Purge Flow Off
- Check Evaporative Emissions (EVAP) canister purge
regulator valve -N80- output Diagnostic Test Mode
(DTM), page 01
-51

P0442 16826 EVAP Emission Contr. Sys.
(Small Leak)
Leak Detected Off
- Check Evaporative Emission (EVAP) system Repair
Manual, Fuel Supply System, Repair Group 20 P0455 16839 EVAP Emission Contr. Sys.
(Gross Leak)
Leak Detected Off
- Check Evaporative Emission (EVAP) system Repair
Manual, Fuel Supply System, Repair Group 20 P0501 16885 Vehicle Speed Sensor
Range/Performance 2
Dcy - Check vehicle speed signal page 24
-168
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01-26

Diagnostic Trouble
Code (DTC)
Malfunction text
MIL
Corrective action
SAE
VAG



P0506 16890 Idle Control System
RPM Lower Than Expected 2
Dcy - Check idle speed page 24
-16
- Check throttle valve control module page 24
-128
- Check fuel pressure, fuel pressure regulator, and
residual fuel pressure page 24
-111

P0507 16891 Idle Control System
RPM Higher Than Expected
P0601 16985 Internal Contr. Module
Memory
Check Sum Error 2
Dcy Replace ECM page 01
-68

P0604 16988 Internal Contr. Module
Random Access
Memory (RAM) Error
P1102 17510 O2 Sensor Heating Circ.,
Bank1-Sensor1
Short to B+ 2
Dcy - Check Oxygen Sensor (O2S) heater -Z19- (bank 1,
sensor 1, before TWC) page 24
-34

P1105 17513 O2 Sensor Heating Circ.,
Bank1-Sensor2
Short to B+ 2
Dcy - Check O2S heater -Z29- (bank 1, sensor 2, behind
TWC) page 24
-52

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01-27

Diagnostic Trouble
Code (DTC)
Malfunction text
MIL
Corrective action
SAE
VAG



P1110 17518 O2 Sensor Heating Circ.,
Bank2-Sensor2
Short to B+ 2
Dcy - Check O2S heater -Z30- (bank 2, sensor 2, behind TWC)
page 24
-52

P1127 17535 Long Term Fuel Trim
mult., Bank1
System too Rich 1) 2
Dcy - Check Mass Air Flow (MAF) sensor -G70- page 24
-68
- Check Heated Oxygen Sensor (HO2S) -G39- (bank 1, sensor
1) and O2S control page 24
-22

- Check Oxygen Sensor (O2S) behind Three Way Catalytic
Converter (TWC) -G130- (bank 1, sensor 2) and O2S control
page 24
-42

- Check fuel pressure, fuel pressure regulator and residual fuel
pressure page 24
-111

- Check fuel injectors page 24
-102
and Output Diagnostic
Test Mode (DTM) page 01
-51

1) The term "mult." = multiplicative; applies to entire engine speed (RPM) and load range.
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01-28

Diagnostic Trouble
Code (DTC)
Malfunction text
MIL
Corrective action
SAE
VAG



P1128 17536 Long Term Fuel Trim
mult., Bank1
System too Lean 1) 2
Dcy - Check Heated Oxygen Sensor (HO2S) -G39- (bank 1, sensor 1)
and O2S control page 24
-22

- Check Oxygen Sensor (O2S) behind Three Way Catalytic
Converter (TWC) -G130- (bank 1, sensor 2) and O2S control
page 24
-42

- Check fuel pressure, fuel pressure regulator and residual fuel
pressure page 24
-111

- Check fuel injectors page 24
-102
and Output Diagnostic
Test Mode (DTM) page 01
-51

- Check EVAP canister purge regulator valve output Diagnostic
Test Mode (DTM), page 01
-51

1) The term "mult." = multiplicative; applies to entire engine speed (RPM) and load range.
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