With Manufacturer's Scan Tool
Generating Readiness Code
Special tools, workshop equipment, testers, measuring instruments and auxiliary items required
- VAG 1551 scan tool (or VAG 1552) with VAG 1551/3 Adapter cable
NOTE: All functions which could previously be performed with VAG 1551/1552 can also be performed with the vehicle diagnostic, testing and information system VAS 5051.
Test prerequisites
- All fuses must be OK.
- The main fuses must be OK.
- The battery voltage must be at least 11.5 V.
- If the vehicle is equipped with air conditioning, this must be switched off.
- Selector lever must be in position "P" or "N" on vehicles with an automatic transmission.
- Exhaust system between Three Way Catalytic Converter (TWC) and cylinder head must be free of leaks
- Ignition switched on, engine not running.
- Fuel Pump (FP) relay -J17- must be OK., checking:
- The signal from Brake Light Switch -F- and Brake Vacuum Vent Valve Switch -F47- -F85- must be OK., checking Testing and Inspection
- Engine Coolant Temperature (ECT) must be 85...110 degrees C See display group 4, display zone 3.
- Intake Air Temperature (IAT) less than 80 degrees C See display group 4, display zone 4.
- Three Way Catalytic Converter (TWC) temperature must be at least 380 degrees C See display group 34, display zone 2.
Work sequence
- Connect VAG 1551 scan tool (or VAG 1552). Then switch ignition on and select Motronic Engine Control Module (ECM) -J220- with the "Address word" 01. (Connecting scan tool and selecting Engine Control Module (ECM)). [1][2][3]Connecting VAG 1551 Scan Tool
Work step 1: Check DTC memory
Indicated on display:
Rapid data transfer HELP
Select function XX
- Operate scan tool taking into account the information on the display:
- Press buttons -0- and -2- for function "Check DTC memory" and confirm entry with Q button.
The number of Diagnostic Trouble Codes (DTCs) stored or "No DTC detected!" will be shown on the display.
X Diagnostic Trouble Codes (DTCs) detected!
If a DTC is stored:
- Repair Diagnostic Trouble Codes (DTCs) printed out using DTC table:
- SAE P0 codes, SAE P0 Codes
- SAE P1 codes, SAE P1 Codes
- SAE P2 codes, SAE P2 Codes
- SAE P3 codes, SAE P3 Codes
If no DTC is stored:
- Press the -> button.
- Continue with work step 3
Work step 2: Erase DTC memory
Indicated on display:
Rapid data transfer HELP
Select function XX
- Press buttons -0- and -5- for the function "Erase DTC memory" and confirm entry with -Q- button.
NOTE: The readiness code is reset or erased each time DTC memory is erased.
Indicated on display:
Rapid data transfer ->
DTC memory is erased!
NOTE: If the ignition is switched off between "Check DTC memory" and "Erase DTC memory" the DTC memory will not be erased.
- Press the -> button.
Work step 3: Adjust the Throttle Valve Control Module -J338- to the Motronic Engine Control Module (ECM) -J220-
Indicated on display:
Rapid data transfer HELP
Select function XX
- Press buttons -0- and -4- for function "Initiate basic setting" and confirm entry with -Q- button.
Indicated on display:
Basic setting
Input display group number XXX
- Press buttons -0-, -6- and -0- for "Display group number 60" and confirm entry with -Q- button.
Indicated on display: (1 to 4 = display zones)
System in basic setting 60 ->
xxx.x % xxx.x % x ADP. runs
- Check specifications in display zones 3 and 4
- Display zone 3: 0 to 8
- Display zone 4: ADP. runs, ADP. OK.
Indicated on display: (1 to 4 = display zones)
System in basic setting 60-> ->
xxx % xxx % 8 ADP. OK.
- Terminate engine basic setting at earliest after 30 seconds by pressing the button.
If the display does not indicate as described:
- Check Throttle Valve Control Module -J338-. Refer under "Powertrain Management/Computers and Control Systems/Electronic Throttle Control Module". Testing and Inspection
If the display indicates as described:
- Start engine and run at idle.
NOTE: Engine must not be switched again off during work sequence.
Work step 4: Requesting temperature
Indicated on display:
Rapid data transfer HELP
Select function XX
- Press buttons -0- and -8- for function "Read measured value (data) block" and confirm entry with Q button.
Indicated on display:
Read measured value block
Input display group number XXX
- Press buttons -0-, -0- and -4- for "Display group number 4" and confirm entry with -Q- button.
Indicated on display: (1 to 4 = display zones)
Read measured value block 4 ->
1 2 3 4
- Read Engine Coolant Temperature value in display zone 3.
Specification: 85 to 110 degrees C
- Read Intake Air Temperature value in display zone 4.
Specification: Ambient temperature less than 80 degrees C
If the specifications are obtained:
- Press the -> button.
Work step 5: Evaporative Emissions (EVAP) Canister system diagnosis (Tank ventilation system)
Indicated on display:
Rapid data transfer HELP
Select function XX
- Press buttons -0- and -4- for function "Initiate basic setting" and confirm entry with -Q- button.
Indicated on display:
Basic setting
Input display group number XXX
- Press buttons -0-, -7- and -1- for "Display group number 71" and confirm entry with -Q- button.
NOTE: The engine must not be loaded during this diagnosis, if this occurs the diagnosis will be interrupted and will not start again until the engine is revved-up.
Indicated on display: (1 to 4 = display zones)
System in basic setting 71 ->
1 2 3 4
If "Reed op." appears in display zone 1:
- Open fuel tank filler cap briefly to release pressure in fuel tank. This will close the reed terminal.
If the diagnosis is initiated by the Motronic Engine Control Module (ECM) -J220- the display in display zone 4 jumps from "Test OFF" to "Test ON".
- Leave engine running at idle until the specification "Sys. OK." is displayed in display zone 4.
NOTE: If the display in display zone 4 jumps from "Test OFF" to "Test ON" during the diagnosis, repeat the diagnosis again. When repeating the diagnosis, the diagnosis can take up to 60 seconds before the display in display zone 4 jumps from "Test OFF" to "Test ON".
If "Sm leak or La leak" (meaning Small leak or Large leak) appears in display zone 2 and "Sys. n.OK." appears in display zone 4:
- Press the -> button.
- Check DTC memory, repair Diagnostic Trouble Codes (DTCs) if necessary and then erase DTC memory, DTC memory, checking and erasing. Reading Diagnostic Trouble Codes
- Read readiness code. If the DTC memory has been erased or the Motronic Engine Control Module (ECM) -J220- was disconnected from battery (B+) positive, the readiness code must be generated again.
If no DTC is stored:
- Check Evaporative Emissions (EVAP) Canister system for leaks:
If "Sys. OK." appears in display zone 4:
- Press the -> button.
Work step 6: Oxygen Sensor (O2S) control diagnosis status before Three Way Catalytic Converter (TWC)
Indicated on display:
Rapid data transfer HELP
Select function XX
- Press buttons -0- and -8- for function "Read measured value (data) block" and confirm entry with -Q- button.
Indicated on display:
Read measured value block
Input display group number XXX
- Press buttons -0-, -3- and -0- for "Display group number 30" and confirm entry with -Q- button.
Indicated on display: (1 to 2 = display zones)
Read measured value block 30 ->
1 2
- Check Oxygen Sensor (O2S) control status before Three Way Catalytic Converter (TWC) (display zone 1):
Specification: 111
Significance of figures in 3 digit number block Display Groups 0-9 (Basic Functions)
NOTE: The bits in display zones 1 will not be set to 1 until the Three Way Catalytic Converter (TWC) temperature rises above 380 degrees C ( See display groups 34, display zone 2).
If the specification is not obtained:
- Press the -> button.
- Check Oxygen Sensor (O2S) heater of Oxygen Sensor (O2S) before Three Way Catalytic Converter (TWC) Testing and Inspection
If the specification is obtained:
- Press the -> button.
Work step 7: Oxygen Sensor (O2S) aging diagnosis of Oxygen Sensor (O2S) before Three Way Catalytic Converter (TWC)
Indicated on display:
Rapid data transfer HELP
Select function XX
- Press buttons -0- and -4- for function "Initiate basic setting" and confirm entry with -Q- button.
Indicated on display:
Basic setting
Input display group number XXX
- Press buttons -0-, -3- and -4- for "Display group number 34" and confirm entry with -Q- button.
Indicated on display: (1...4 = display zones)
System in basic setting 34 ->
1 2 3 4
- Depress brake pedal and hold.
- Depress accelerator down to full throttle position.
Engine speed will be increased by Motronic Engine Control Module (ECM) -J220- to approx. 2300 rpm.
- Depress brake pedal and accelerator down until display in display zone 4 jumps from "Test OFF" to "Test ON", when performing this test the Three Way Catalytic Converter (TWC) temperature in display zone 2 must be at least 380 degrees C.
NOTE: This process can take approx. 90 seconds.
- Depress brake pedal and accelerator down until display zone 4 displays specification "B1-P1 OK.".
- Release brake and accelerator pedals.
If "B1 P1 n.OK." appears in display zone 4:
- Press the -> button.
- Check DTC memory, repair Diagnostic Trouble Codes (DTCs) if necessary and then erase DTC memory, DTC memory, checking and erasing. Reading Diagnostic Trouble Codes
- Read readiness code. If the DTC memory has been erased or the Motronic Engine Control Module (ECM) -J220- was disconnected from battery (B+) positive, the readiness code must be generated again.
If no DTC is stored:
- Check aging of Oxygen Sensor (O2S) before Three Way Catalytic Converter (TWC). Testing and Inspection
If "B1 P1 OK." appears in display zone 4:
- Press C button.
Work step 8: Fuel supply system diagnosis (part load)
Indicated on display:
Basic setting
Input display group number XXX
- Press buttons -2-, -1- and -6- for "Display group number 216" and confirm entry with -Q- button.
Indicated on display: (1 to 4 = display zones)
System in basic setting 216 ->
1 2 3 4
- Depress brake pedal and hold.
- Depress accelerator down to full throttle position.
Engine speed will be increased by Motronic Engine Control Module (ECM) -J220- to approx. 2300 rpm.
- Depress brake pedal and accelerator down until display zone 4 displays (after approx. 75 seconds) specification "xxxxx100".
- Release brake and accelerator pedals.
If the display does not indicate as described:
- Press the -> button.
- Check DTC memory, repair Diagnostic Trouble Codes (DTCs) if necessary and then erase DTC memory, DTC memory, checking and erasing. Reading Diagnostic Trouble Codes
- Read readiness code. If the DTC memory has been erased or the Motronic Engine Control Module (ECM) -J220- was disconnected from battery (B+) positive, the readiness code must be generated again.
If the display indicates as described:
- Press the -> button.
Work step 9: Oxygen Sensor (O2S) control diagnosis status after Three Way Catalytic Converter (TWC)
Indicated on display:
Rapid data transfer HELP
Select function XX
- Press buttons -0- and -8- for function "Read measured value (data) block" and confirm entry with -Q- button.
Indicated on display:
Read measured value block
Input display group number XXX
- Press buttons -0-, -3- and -0- for "Display group number 30" and confirm entry with -Q- button.
Indicated on display: (1...2 = display zones)
Read measured value block 30 ->
1 2
- Check Oxygen Sensor (O2S) control status after Three Way Catalytic Converter (TWC) (display zone 2): Specification: 111
Significance of figures in 3 digit number block. Display Groups 0-9 (Basic Functions)
NOTE: The bits in display zone 2 will not be set to 1 until the Three Way Catalytic Converter (TWC) temperature rises above 380 degrees C (See display groups 34, display zone 2).
If the specification is not obtained:
- Press the -> button.
- Check Oxygen Sensor (O2S) heater of Oxygen Sensor (O2S) after Three Way Catalytic Converter (TWC). Testing and Inspection
If the specification is obtained:
- Press the -> button.
Work step 10: Oxygen Sensor (O2S) aging diagnosis of Oxygen Sensor (O2S) after Three Way Catalytic Converter (TWC)
Indicated on display:
Rapid data transfer HELP
Select function XX
- Press buttons -0- and -4- for function "Initiate basic setting" and confirm entry with -Q- button.
Indicated on display:
Basic setting
Input display group number XXX
- Press buttons -0-, -4- and -3- for "Display group number 43" and confirm entry with -Q- button.
Indicated on display: (1 to 4 = display zones)
System in basic setting 43 ->
1 2 3 4
- Depress brake pedal and hold.
- Depress accelerator down to full throttle position.
Engine speed will be increased by Motronic Engine Control Module (ECM) -J220- to approx. 2300 rpm.
- Depress and hold brake pedal and accelerator until display in display zone 4 jumps from "Test OFF" to "Test ON", when performing this test the Three Way Catalytic Converter (TWC) temperature in display zone 2 must be at least 380 degrees C.
NOTE: This process can take approx. 30 seconds.
- Depress and hold brake pedal and accelerator until display zone 4 displays specification "B1 P2 OK.".
- Release brake and accelerator pedals.
If "B1 P2 n.OK." appears in display zone 4:
- Press the -> button.
- Check DTC memory, repair Diagnostic Trouble Codes (DTCs) if necessary and then erase DTC memory, DTC memory, checking and erasing. Reading Diagnostic Trouble Codes
- Read readiness code. If the DTC memory has been erased or the Motronic Engine Control Module (ECM) -J220- was disconnected from battery (B+) positive, the readiness code must be generated again.
If no DTC is stored:
- Check aging of Oxygen Sensor (O2S) after Three Way Catalytic Converter (TWC). Testing and Inspection
If "B1 P2 OK." appears in display zone 4:
- Press -C- button.
Work step 11: Oxygen Sensor (O2S) diagnosis after Three Way Catalytic Converter (TWC) (operational readiness)
Indicated on display:
Basic setting
Input display group number XXX
- Press buttons -0-, -3- and -6- for "Display group number 36" and confirm entry with -Q- button.
Indicated on display: (1...2 = display zones)
System in basic setting 36 ->
1 2
If the diagnosis is initiated by the Motronic Engine Control Module (ECM) -J220- the display in display zone 2 jumps from "Test OFF" to "Test ON".
- Leave engine running at idle until display zone 2 shows the specification "B1 P2 OK.".
NOTE: This process can take approx. 30 seconds.
If "B1 P2 n.OK." appears in display zone 4:
- Press the -> button.
- Check DTC memory, repair Diagnostic Trouble Codes (DTCs) if necessary and then erase DTC memory, DTC memory, checking and erasing. Reading Diagnostic Trouble Codes
- Read readiness code. If the DTC memory has been erased or the Motronic Engine Control Module (ECM) -J220- was disconnected from battery (B+) positive, the readiness code must be generated again.
If no DTC is stored:
- Check Oxygen Sensor (O2S) and Oxygen Sensor (O2S) control after Three Way Catalytic Converter (TWC). Testing and Inspection
If "B1 P2 OK." appears in display zone 4:
- Press -C- button.
Work step 12: Three Way Catalytic Converter (TWC) diagnosis (checking conversion)
NOTE: The diagnosis will only be ended if the Oxygen Sensor (O2S) aging diagnosis for Oxygen Sensor (O2S)s before and after Three Way Catalytic Converter (TWC) is first successfully completed.
Indicated on display:
Basic setting
Input display group number XXX
- Press buttons -0-, -4- and -6- for "Display group number 46" and confirm entry with -Q- button.
Indicated on display: (1 to 4 = display zones)
System in basic setting 46 ->
1 2 3 4
- Depress brake pedal and hold.
- Depress accelerator down to full throttle position.
Engine speed will be increased by Motronic Engine Control Module (ECM) -J220- to approx. 2300 rpm.
Only continue with the test when
- The Three Way Catalytic Converter (TWC) temperature is above 380 degrees C (display zone 2).
- Depress brake pedal and accelerator down and hold until display in display zone 4 jumps from "Test OFF" to "Test ON".
NOTE: This process can take approx. 80 seconds.
- Depress and hold brake pedal and accelerator until display zone 4 displays specification "Cat. B1 OK.".
- Release brake and accelerator pedals.
If "CatB1 n.OK." appears in display zone 4:
- Press the -> button.
- Check DTC memory, repair Diagnostic Trouble Codes (DTCs) if necessary and then erase DTC memory, DTC memory, checking and erasing. Reading Diagnostic Trouble Codes
- Read readiness code. If the DTC memory has been erased or the Motronic Engine Control Module (ECM) -J220- was disconnected from battery (B+) positive, the readiness code must be generated again.
If no DTC is stored:
- Press buttons -0- and -6- for the function "End output" and confirm entry with the -Q- button.
- Switch off ignition.
- Replace front exhaust pipe with Three Way Catalytic Converter (TWC):
If "Cat B1 OK." appears in display zone 4:
- Press -C- button.
Work step 13: Fuel supply system diagnosis (idle speed)
Indicated on display:
Basic setting
Input display group number XXX
- Press buttons -2-, -1- and -6- for "Display group number 216" and confirm entry with -Q- button.
Indicated on display: (1...4 = display zones)
System in basic setting 216 ->
1 2 3 4
- Observe figure displayed in display zone 4 - Specification: xxxxx100
- Allow engine to run at idle until display zone 4 displays (after approx. 30 seconds) - Specification: xxxx1100.
If the display does not indicate as described:
- Press the -> button.
- Check DTC memory, repair Diagnostic Trouble Codes (DTCs) if necessary and then erase DTC memory, DTC memory, checking and erasing. Reading Diagnostic Trouble Codes
- Read readiness code. If the DTC memory has been erased or the Motronic Engine Control Module (ECM) -J220- was disconnected from battery (B+) positive, the readiness code must be generated again.
If the display indicates as described:
- Press -C- button.
Work step 14: Evaporative Emissions (EVAP) Canister system solenoid valve 1 diagnosis (Tank ventilation system)
Indicated on display:
Basic setting
Input display group number XXX
- Press buttons -0-, -7- and -0- for "Display group number 70" and confirm entry with -Q- button.
NOTE: The engine must not be loaded during this diagnosis, if this occurs the diagnosis will be interrupted and will not start again until the engine is revved-up.
Indicated on display: (1 to 4 = display zones)
System in basic setting 70 ->
1 2 3 4
If the diagnosis is initiated by the Motronic Engine Control Module (ECM) -J220- the display in display zone 4 jumps from "Test OFF" to "Test ON".
NOTE: ^ This process can take approx. 30 seconds.
- Leave engine running at idle until display zone 4 displays the specification TBV OK..
^ TBV stands for Evaporative Emission (EVAP) Canister Purge control Valve (Evaporative Emissions (EVAP) Canister system solenoid valve 1).
If "TBV n. OK." appears in display zone 4:
- Press the -> button.
- Check DTC memory, repair Diagnostic Trouble Codes (DTCs) if necessary and then erase DTC memory, DTC memory, checking and erasing. Reading Diagnostic Trouble Codes
- Read readiness code. If the DTC memory has been erased or the Motronic Engine Control Module (ECM) -J220- was disconnected from battery (B+) positive, the readiness code must be generated again.
If no DTC is stored:
- Press buttons -0- and -6- for the function "End output" and confirm entry with the -Q- button.
- Switch off ignition.
- Check breather lines to Evaporative Emissions (EVAP) Canister (maybe kinked).
- Check Evaporative Emissions (EVAP) Canister system for leaks:
If "TBV OK." appears in display zone 4:
- Press -C- button.
Work step 15: Secondary air system diagnosis
Indicated on display:
Basic setting
Input display group number XXX
- Press buttons -0, -7- and -7- for "Display group number 77" and confirm entry with -Q- button.
NOTE: The engine must not be loaded during this diagnosis, if this occurs the diagnosis will be aborted and will not start again until the engine is revved-up.
Indicated on display: (1 to 4 = display zones)
System in basic setting 77 ->
1 2 3 4
If the diagnosis is initiated by the Motronic Engine Control Module (ECM) -J220- the display in display zone 4 jumps from "Test OFF" to "Test ON".
NOTE: This process can take approx. 40 seconds.
- Leave engine running at idle until display zone 4 displays the specification "Syst. OK."
If "Syst.n.OK." appears in display zone 4:
- Press the -> button.
- Check DTC memory, repair Diagnostic Trouble Codes (DTCs) if necessary and then erase DTC memory, DTC memory, checking and erasing. Reading Diagnostic Trouble Codes
- Read readiness code. If the DTC memory has been erased or the Motronic Engine Control Module (ECM) -J220- was disconnected from battery (B+) positive, the readiness code must be generated again.
If no DTC is stored:
- Press buttons -0- and -6- for the function "End output" and confirm entry with the -Q- button.
- Switch off ignition.
- Check combi-valve:
If "Syst. OK." appears in display zone 4:
- Press the -> button.
Work step 16: Read readiness code
- Read readiness code Readiness Code Reading.
Readiness code, generating (overview)
Work steps 1 to 5:
Work steps 6 to 9:
Work steps 10 to 11:
Work steps 12 to 13:
Work steps 14 to 16:
