Function
Under "address word 33 - OBD" , various diagnostic modes for Engine Control Module (ECM) and Transmission Control Module -TCM- (in vehicles with automatic transmission) can be selected via diagnostic tester.
The following diagnostic modes monitor all components and systems which influence the emission quality.
Note. The PIDs activated depend on engine code. ECM reports with module number 10 - Engine electronics. Transmission Control Module (TCM) (vehicles with automatic transmission) reports with module number 1A - Transmission Electronics.
- Coolant temperature must be at least 80°C --> PID 5, Coolant temperature.
- Connect diagnostic tester --> «Diagnostic tester, connecting»(/audi/tt/8n-1998-2003/remont/blowers-superchargers-turbochargers/#18l-4-cyl-5v-turbo-generic-scan-tool-engine-codes-amu-bea-atc-awp) .
- Depending on the desired operating condition
Switch ignition on
Or
Start engine and let run at idle.
- Under address word 33, select "Diagnostic mode 1: Checking measuring values."
- Select the desired measuring values "PID XX".
Note. The specified values for the respective measuring values can be found at the respective component- and function tests. The following list only serves as an overview. The measuring values are organized according to PIDs (parameter identifiers).
| PID | Diagnostic mode | Module number 10 Engine electronics | Module number 1A Transmission electronics | ||
|---|---|---|---|---|---|
| 01 | Monitoring status since erasing DTC memory | X | |||
| 03 | Condition of the fuel system | X | |||
| 04 | Calculated load condition value | X | X | ||
| 05 | Coolant temperature | X | X | ||
| 06 | Short time gasoline-air ratio bank 1 | X | |||
| 07 | Gasoline-air ratio bank 1 | X | |||
| 12 | Engine rotations per minute | X | X | ||
| 13 | Vehicle speed | X | X | ||
| 14 | Valve timing adjustment at 1. cyl. to "advance" | X | |||
| 15 | Intake air temperature | X | |||
| PID | Diagnostic mode | Module number 10 Engine electronics | Module number 1A Transmission electronics | ||
|---|---|---|---|---|---|
| 16 | Air flow quantity at Mass Air Flow (MAF) sensor | X | |||
| 17 | Throttle valve position (absolute) | X | X | ||
| 18 | Availability status of secondary air | X | |||
| 19 | Component location of oxygen sensors | X | |||
| 21 | Bank 1 sensor 2 | X | |||
| 28 | OBD requirement for which this vehicle is designed | X | X | ||
| 33 | Distance driven with MIL ON | X | X | ||
| 52 | Oxygen sensor value/pump current bank 1 sensor 1 | X | |||
| 65 | Diagnostic status | X | |||
| 66 | Voltage supply | X | |||
- End diagnosis and switch ignition off.
This diagnostic mode displays the operating conditions at which an emission relevant malfunction was detected and stored by both the Engine Control Module (ECM) and Transmission Control Module (TCM).
- Connect diagnostic tester --> «Diagnostic tester, connecting»(/audi/tt/8n-1998-2003/remont/blowers-superchargers-turbochargers/#18l-4-cyl-5v-turbo-generic-scan-tool-engine-codes-amu-bea-atc-awp) .
- Depending on the desired operating condition
Switch ignition on
Or
Start engine and let run at idle.
- Under address word 33, select "Diagnostic mode 2: Check operating conditions."
- Select the desired operating condition "PID XX".
Note. The operating conditions are organized according to PIDs (parameter identifiers). The PIDs activated depend on engine code.
| PID | Diagnostic mode | Module number 10 Engine electronics | Module number 1A Transmission electronics | ||
|---|---|---|---|---|---|
| 02 | DTC which belongs to Freeze Frame 0 | X | |||
| 03 | Condition of the fuel system | X | |||
| 04 | Calculated load condition value | X | X | ||
| 05 | Coolant temperature | X | X | ||
| 06 | Short time gasoline-air ratio bank 1 | X | |||
| 07 | Gasoline-air ratio bank 1 | X | |||
| 12 | Engine rotations per minute | X | X | ||
| 13 | Vehicle speed | X | X | ||
| 14 | Valve timing adjustment at 1. cyl. to "advance" | X | |||
| 15 | Intake air temperature | X | |||
| 16 | Air flow quantity at Mass Air Flow (MAF) sensor | X | |||
| 17 | Throttle valve position (absolute) | X | X | ||
| 18 | Availability status of Secondary Air Injection (AIR) | X | |||
| 66 | Voltage supply | X | |||
If DTCs are displayed in "PID 02"
- Repair stored malfunctions according to DTC table
- SAE P0xxx-DTCs --> «SAE P0xxx DTCs»(/audi/tt/8n-1998-2003/remont/blowers-superchargers-turbochargers/#18l-4-cyl-5v-turbo-generic-scan-tool-engine-codes-amu-bea-atc-awp)
- SAE P1xxx-DTCs --> «SAE P1xxx-DTCs»(/audi/tt/8n-1998-2003/remont/blowers-superchargers-turbochargers/#18l-4-cyl-5v-turbo-generic-scan-tool-engine-codes-amu-bea-atc-awp)
- SAE P2xxx-DTCs --> «SAE P2xxx-DTCs»(/audi/tt/8n-1998-2003/remont/blowers-superchargers-turbochargers/#18l-4-cyl-5v-turbo-generic-scan-tool-engine-codes-amu-bea-atc-awp) .
- SAE P3xxx-DTCs --> «SAE P3xxx-DTCs»(/audi/tt/8n-1998-2003/remont/blowers-superchargers-turbochargers/#18l-4-cyl-5v-turbo-generic-scan-tool-engine-codes-amu-bea-atc-awp) .
- End diagnosis and switch ignition off.
This diagnostic mode indicates all stored DTCs of components and systems which are emission relevant.
Malfunction Indicator Lamp (MIL) in instrument cluster lights up for one DTC entry.