Work step 11: Diagnosis of catalytic converter

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Increase engine speed to approximately 1800 - 2400/RPM
Catalyst temperature must exceed 540 °C display field 2
Return engine to idle. Test starts when catalyst temperature falls below 540 °C but remains above 400 °C.

Indicated on display

Fig 1: Identifying VAG1551 Scan Tool Display Work Step -11 (1 Of 2)

Courtesy of AUDI OF AMERICA, INC.

Press buttons -0-, -4- and -6- to select display group number "046" and confirm input with -Q- button.

Indicated on display

Fig 2: Identifying VAG1551 Scan Tool Display Work Step -11 (2 Of 2)

Courtesy of AUDI OF AMERICA, INC.

Check specified value in display field 4.

NOTE: The test duration for catalytic converter diagnosis takes approx.: 60 seconds.

DISPLAY GROUP 046: DIAGNOSTIC OF CATALYTIC CONVERTER (BANK 1)

	Display fields
	1	2	3	4
Display group 046: Diagnostic of catalytic converter (Bank 1)
Display	xxxx/RPM	xxx °C	x.x s	---
Indicated	Engine speed (RPM)	Catalyst temperature	Catalytic converter conversion	Diagnostic condition
Work range	0 to 6800/RPM	70 to 850 °C	0.0 to 1.0 Seconds	Test OFF Test ON Cat B1 OK Cat B1 not OK
Values	1800 to 2400/RPM	greater than 400 °C less than 540 °C	0.0 to 0.55 seconds	Cat B1 OK
Note				If "Cat B1 not OK" is displayed: Check DTC memory, see DIAGNOSTIC TROUBLE CODE (DTC) MEMORY, CHECKING AND ERASING . If no malfunction is stored replace catalytic converter.

If the specified value "Cat B1 OK" is reached:

Press -C- button
Press buttons -0-, -4- and -7- to select display group number "047" and confirm input with -Q- button.

DISPLAY GROUP 047: DIAGNOSTIC OF CATALYTIC CONVERTER (BANK 2)

	Display fields
	1	2	3	4
Display group 047: Diagnostic of catalytic converter (Bank 2)
Display	xxxx/RPM	xxx °C	x.x seconds	---
Indicated	Engine speed (RPM)	Catalyst temperature	Catalytic converter conversion	Diagnostic condition
Work range	0 to 6800/RPM	70 to 850 °C	0.0 to 1.0 Seconds	Test OFF Test ON Cat B2 OK Cat B2 not OK
Value	1800 to 2400/RPM	greater than 400 °C less than 540 °C	0.0 to 0.55 seconds	Cat B2 OK
Note				If "Cat B2 not OK" is displayed: Check DTC memory, see DIAGNOSTIC TROUBLE CODE (DTC) MEMORY, CHECKING AND ERASING . If no malfunction is stored replace catalytic converter.

If the specified value "Cat B2 OK" is reached:

Press -C- button