Readiness code, generating

Special tools and equipment

VAG1551 Scan Tool (or VAG1552 mobile scan tool) with VAG1551/3 cable

Fig 1: V.A.G 1788/10 Speed Adjuster Tool

Courtesy of VOLKSWAGEN UNITED STATES, INC.

VAG1788/10 RPM adjuster

Test requirements

Vehicle stationary
For vehicles with automatic transmission, selector lever must be in -P- or -N-.
All electrical consumers, for example, lights and rear window defroster must be switched off.
Coolant temperature less than 50 ° C. Refer to Display group 04, display field 3

Intake Air Temperature (IAT) less than 30 ° C. Refer to Display group 04, display field 4

Work procedure

Connect VAG 1551 scan tool (VAG1552). Switch ignition on and select Engine Control Module (ECM) using address word 01 (connecting scan tool and selecting ECM. Refer to VAG1551 Scan Tool (ST), connecting and selecting "Engine Electronics" address word 01 ).

Work step 1: Check DTC Memory

Rapid data transfer HELP
Select function XX

Indicated on display

Press buttons -0- and -2- to select "Check DTC Memory" function 02. Press -Q- button to confirm input.

X DTC recognized

Number of stored DTCs or "No DTC recognized" will be indicated on display.

If a DTC is stored:

Repair malfunctions that were printed out using DTC table:

SAE P0-Codes. Refer to Diagnostic Trouble Code (DTC) table: SAE P0-Codes

SAE P1-Codes. Refer to Diagnostic Trouble Code (DTC) table: SAE P1-Codes

If no DTCs are stored:

Press → button.

Work step 2: Erase DTC Memory

Rapid data transfer HELP
Select function XX

Indicated on display

Press buttons -0- and -5- to select "Erase DTC Memory" function 05. Press -Q- button to confirm input.

NOTE: The readiness code is reset/erased every time DTC memory is erased.

Rapid data transfer →
DTC Memory is erased!

Indicated on display

NOTE: If ignition was switched off between the steps "Check DTC memory" and "Erase DTC memory", DTC memory will not be erased.

Press → button.

Work step 3: Temperature check

Rapid data transfer HELP
Select function XX

Indicated on display

Press buttons -0- and -8- to select "Read measuring value block" function 08. Press -Q- button to confirm input.

Read Measuring Value Block HELP
Input display group number XXX

Indicated on display

Press buttons -0-, -0- and -4- to select "Display group number 4". Press -Q- button to confirm input.

Read Measuring Value Block 4 →
1 2 3 4

Indicated on display (1-4 = display fields)

Read coolant temperature value in display field 3.

Specification: maximum 50 ° C

Read Intake Air Temperature (IAT) value in display field 4.

Specification: maximum 30 ° C

If indications resemble description:

Start engine, and let it idle.

NOTE:

Engine must not be shut off again during work sequence.

Press → button.

Rapid data transfer HELP
Select function XX

Indicated on display

Work step 4: Diagnostic of leak detection system

Press buttons -0- and -4- to select "Basic Setting" function 04. Press -Q- button to confirm input.

Basic Setting
Input display group number XXX

Indicated on display

Press buttons -0-, -7- and -1- to select "Display group number 71". Press -Q- button to confirm input.

Basic Setting 71 "
1 2 3 4

Indicated on display (1-4 = display fields)

Continue to let engine run at idle.

If diagnostic is initiated by the Engine Control Module (ECM), the indication in display field 4 will jump from "Test OFF" to "Test ON".

Continue to let engine run at idle until display field 4 indicates:

"Sys. OK".

NOTE: If indication in display field 4 jumps from "Test ON" to "Test OFF" during the test and display field 2 indicates "Aborted", repeat "Leak detection diagnostic".

When diagnostic is repeated, it can last up to approx. 60 seconds before indication in display field 4 switches from "Test OFF" to "Test ON".

Work step 5: Diagnostic of tank ventilation system

Coolant temperature larger than 60 ° C. Refer to Display group 04, display field 3

Press button -1- (VAG1551) or ↓ button (VAG1552).

System in Basic Setting 70 →
1 2 3 4

Indicated on display (1 - 4 = display fields)

If diagnostic is initiated by the Engine Control Module (ECM), the indication in display field 4 will jump from "Test OFF" to "Test ON".

Continue to let engine run at idle until display field 4 indicates:

"TVV OK"

If indications do not resemble description:

Check DTC memory. Refer to DTC memory of Engine Control Module (ECM), checking (scan tool function 02) and erasing (scan tool function 05) .

If indications resemble description:

Press -C- button.

Work step 6: Diagnostic fuel system

Basic Setting
Input display group number XXX

Indicated on display

Press buttons -1-, -0- and -7- to select "Display group number 107". Press -Q- button to confirm input.

System in Basic Setting 107 →
1 2 3 4

Indicated on display (1-4 = display fields)

If diagnostic is initiated by the Engine Control Module (ECM), the indication in display field 4 will jump from "Test OFF" to "Test ON".

Continue to let engine run at idle until display field 4 indicates:

"Sys. OK"

If indications do not resemble description:

Check DTC memory. Refer to DTC memory of Engine Control Module (ECM), checking (scan tool function 02) and erasing (scan tool function 05) .

If indications resemble description:

Press -C- button.

Work step 7: Diagnostic of Secondary Air Injection (AIR) system

Basic Setting
Input display group number XXX

Indicated on display

Press buttons -0-, -7- and -7- to select "Display group number 77". Press -Q- button to confirm input.

System in Basic Setting 77 →
1 2 3 4

Indicated on display (1-4 = display fields)

Use VAG1788/10 RPM adjuster to adjust engine RPM to 1800-2200 RPM:

If diagnostic is initiated by the Engine Control Module (ECM), the indication in display field 4 will jump from "Test OFF" to "Test ON".

Continue to let engine run at idle until display field 4 indicates:

"Sys. OK"

If indications do not resemble description:

Check DTC memory. Refer to DTC memory of Engine Control Module (ECM), checking (scan tool function 02) and erasing (scan tool function 05) .

If indications resemble description:

Press -C- button.

Work step 8: Diagnostic operational readiness of oxygen sensor behind catalytic converter

Basic Setting
Input display group number XXX

Indicated on display

Press buttons -0-, -3- and -6- to select "Display group number 36".
Press -Q- button to confirm input.

System in Basic Setting 36 →
1 2 3 4

Indicated on display (1 - 4 = display fields)

Continue to hold RPM at 1800-2200 until display field 2 indicates specified value:

"B1-S2 OK".

If indications do not resemble description:

Check DTC memory. Refer to DTC memory of Engine Control Module (ECM), checking (scan tool function 02) and erasing (scan tool function 05) .

If indications resemble description:

Press → button.

Work step 9: Diagnostic of oxygen sensor aging before catalytic converter (monitoring period duration)

Rapid data transfer HELP
Select function XX

Indicated on display

Press buttons -0- and -8- to select "Read measuring value block" function 08. Press -Q- button to confirm input.

Read Measuring Value Block
Input display group number XXX

Indicated on display

Press buttons -0-, -3- and -4- to select "Display group number 34".
Press -Q- button to confirm input.

Read Measuring Value Block 34 →
1 2 3 4

Indicated on display (1 - 4 = display fields)

Hold RPM until catalytic converter temperature in display field 2 climbs to over 350 ° C.
Press -C- button.

Read Measuring Value Block
Input display group number XXX

Indicated on display

Press buttons -0-, -3- and -0- to select "Display group number 30". Press -Q- button to confirm input.

Read Measuring Value Block 30 →
1 2 3 4

Indicated on display (1 - 4 = display fields)

Check operational condition of oxygen sensor control before catalytic converter (display field 1):

Specification: 111

Check operational condition of oxygen sensor control behind catalytic converter (display field 2):

Specification: 11 x

NOTE: The bits in display fields 2 and 4 are only set to 1 after catalytic converter temperature has risen to above 350 ° C (Refer to display group 34, display field 2).

Meaning of 3 digit number block in display fields 1 and 2

When display positions = 1
1	2	3
		1	Oxygen sensor control active
	1		Oxygen sensor operationally ready
1			Oxygen sensor heating on

If specified values are not obtained:

Check DTC memory. Refer to DTC memory of Engine Control Module (ECM), checking (scan tool function 02) and erasing (scan tool function 05) .

If specified values are obtained:

Press → button.

Rapid data transfer HELP
Select function XX

Indicated on display

Press buttons -0- and -4- to select "Basic Setting" function 04. Press -Q- button to confirm input.

Basic Setting
Input display group number XXX

Indicated on display

Press buttons -0-, -3- and -4- to select "Display group number 34". Press -Q- button to confirm input.

System in Basic Setting 34 →
1 2 3 4

Indicated on display (1-4 = display fields)

Hold engine speed at 1800-2200 RPM until indication in display field 4 jumps from

"Test OFF" to "Test ON".

Catalytic converter temperature in display field 2 must be 350-500 ° C.

Check period duration in display field 3:

Specification: maximum 3.3 s

Continue to hold RPM at 1800-2200 until display field 4 indicates:

"B1-S1 OK"

If indications do not resemble description:

Check DTC memory. Refer to DTC memory of Engine Control Module (ECM), checking (scan tool function 02) and erasing (scan tool function 05) .

If indications resemble description:

Remove VAG1788/10 from accelerator pedal.
Press -C- button.

Work step 10: Diagnostic of oxygen sensor control system

Press buttons -0-, -3- and -7- to select "Display group number 37".
Press -Q- button to confirm input.

System in Basic Setting 37 →
1 2 3 4

Indicated on display (1 - 4 = display fields)

If diagnostic is initiated by the Engine Control Module (ECM), the indication in display field 4 will jump from "Test OFF" to "Test ON".

Continue to let engine run at idle until display field 4 indicates:

"Sys. OK"

If indications do not resemble description:

Check DTC memory. Refer to DTC memory of Engine Control Module (ECM), checking (scan tool function 02) and erasing (scan tool function 05) .

If indications resemble description:

Press -C- button.

Work step 11: Diagnostic of oxygen sensor aging behind catalytic converter

Press buttons -0-, -4- and -3- to select "Display group number 43". Press -Q- button to confirm input.

System in Basic Setting 43 →
1 2 3 4

Indicated on display (1 - 4 = display fields)

Use VAG1788/10 RPM adjuster to adjust engine RPM to 1800-2200 RPM:
Hold engine speed at 1800-2200 RPM until indication in display field 4 jumps from

"Test OFF" to "Test ON".

Catalytic converter temperature in display field 2 must be at least 300 ° C.

Continue to hold RPM at 1800-2200 until display field 4 indicates:

"B1-S2 OK"

If indications do not resemble description:

Check DTC memory. Refer to DTC memory of Engine Control Module (ECM), checking (scan tool function 02) and erasing (scan tool function 05) .

If indications resemble description:

Press -C- button.

Work step 12: Diagnostic of catalytic converter

NOTE: This diagnostic can only be completed if the diagnostic of oxygen sensor aging has already been performed successfully.

Basic Setting
Input display group number XXX

Indicated on display

Press buttons -0-, -4- and -6- to select "Display group number 46". Press -Q- button to confirm input.

System in Basic Setting 46 →
1 2 3 4

Indicated on display (1 - 4 = display fields)

Hold engine speed at 1800-2200 RPM until indication in display field 4 jumps from

"Test OFF" to "Test ON".

Catalytic converter temperature in display field 2 must be at least 400 ° C.

Continue to hold RPM at 1800-2200 until display field 4 indicates:

"B1-S1 OK"

If indications do not resemble description:

Check DTC memory. Refer to DTC memory of Engine Control Module (ECM), checking (scan tool function 02) and erasing (scan tool function 05) .

If indications resemble description:

Press → button.
Remove VAG1788/10 from accelerator pedal.
Press buttons -0- and -6- to select "End Output" function 06. Press -Q- button to confirm input.
Read readiness code. Refer to Readiness code, checking .

Generating readiness code, work steps 1-6

Work step Function/Diagnostic		Function /Block	Display field 1	Display field 2	Display field 3	Display field 4	Test condition
1	Check DTC Memory	02/---	---	---	---	---	Ignition on
2	Erase DTC Memory	05/---	---	---	---	---	Ignition on
3	Temperature check	08/4	Engine speed	Battery voltage	Coolant	Intake air	---
			640-820 RPM	8.0-15.0 V	max. 50 ° C	max. 30 ° C
4	Leak detection	04/71	REED condition	Text	Text	Result	Idle
			REED closed	---	END Measurement	System OK
5	Tank ventilation	04/70	Percent open, solenoid valve	Oxygen sensor control		Result	Idle
	EVAP canister purge valve -N80-		0.0 - 10.0 %	-7.0 to -23.0 or 7.0 to 23.0 %		TVV OK
6	Fuel supply	04/107	Engine speed	Oxygen sensor control		Result	---
			640 - 820 RPM	-23.0 to 23.0 %		System OK

Generating readiness code, work steps 7-12

Work step Function/Diagnostic		Function/ Block	Display field 1	Display field 2	Display field 3	Display field 4	Test condition
7	Secondary Air Injection (AIR) system	04/77	Engine speed	Air mass Engine	Air mass Secondary Air Injection (AIR)	Result	---
			1800-2200 RPM	5.0 - 12.0 g/s	2.0 - 5.0 g/s	System OK
8	Sensor readiness	04/36	Sensor voltage behind cat.	Result			1800 - 2200 RPM
	behind catalytic converter		0.1 - 0.9 V	B1-S2 OK
9	Sensor aging	04/34	Engine speed	Cat. temp.	Period duration	Result	---
	before catalytic converter		1800-2200 RPM	min. 350 ° C	0.0 - 3.3 s	B1-S1 OK
10	Oxygen sensor control	04/37	Engine load	Sensor voltage behind cat.	Dwell time	Result	1800 - 2200 RPM
	Dwell time		12.0 - 30.0 %	0.1 - 00.9 V	-1200 to 1200 ms	System OK
11	Sensor aging	04/43	Engine speed	Cat. temp.	Sensor voltage behind cat.	Result	---
	Behind catalytic converter		1800-2200 RPM	min. 300 ° C	0.1 - 0.9 V	B1-S2 OK
12	Conversion	04 / 46	Engine speed	Cat. temp.	conversion	Result	---
	Catalytic converter		1800-2200 RPM	min. 400 ° C	---	Cat B1 OK