Work step: 18

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Diagnostic test: Oxygen Sensor (O2S) heating (before three way catalytic converter)

Display will appear as shown

Fig 1: VAG 1551/1552 Scan Tool Display: Readiness Code, Creating, Work Step 18 (1 Of 3)

Press buttons -1-, -2- and -0- to input display group 120.
Press -Q- button to confirm input.

Display will appear as shown (1 -4 = display fields)

Fig 2: VAG 1551/1552 Scan Tool Display: Readiness Code, Creating, Work Step 18 (2 Of 3)

Increase engine speed between 2200 and 2800 RPM and check specifications.

DISPLAY GROUP 120, FUNCTION: 04

	Display fields
	1	2	3	4
Display group: 120 Function: 04
Display	xxx.x °C	xxx s	xx.x Ω	xxxx xxxx
Indicated	Three way catalytic converter temperature	O2S heater diagnostic blocking time after heater on	O2S heater resistance	Diagnostic conditions
Specific.	At least 360 °C	Approx. 151 s -	5.9 to 24.2 Ω -	1111 x100 x = Not relevant
Working range	0.0 to 999.9 °C	0.0 to 500 s	0.0 to 65.0 Ω

RELEVANCE OF 8 DIGIT NUMBER BLOCK IN DISPLAY FIELD 4

Relevance of 8 digit number block in display field 4
1	2	3	4	5	6	7	8	Specifications of diagnostic conditions
1								O2S heating before Three Way Catalytic Converter (TWC) switched on
	1							Heated Oxygen Sensor (HO2S) before TWC vaporization point exceeded
		1						HO2S before TWC operationally ready
			1					O2S heating before TWC operationally ready
					1			CYCLE Bit = Diagnosis completed
						0		Diagnosis malfunction free
							0	DTC memory malfunction free

Press -3- button (VAG 1551 scan tool) or button (VAG 1552)

Display will appear as shown (1 to 4 = display fields)

Fig 3: VAG 1551/1552 Scan Tool Display: Readiness Code, Creating, Work Step 18 (3 Of 3)

Increase engine speed between 2200 and 2800 RPM and check specifications.

DISPLAY GROUP 121, FUNCTION: 04

	Display fields
	1	2	3	4
Display group: 121 Function: 04
Display	xxx.x °C	xxx s	xx.x Ω	xxxx xxxx
Indicated	Three way catalytic converter temp.	O2S heater diagnostic blocking time after heater on	O2S heater resistance	Diagnostic conditions
Specific.	At least 360 °C	Approx. 150 secs -	5.9 to 24.2 Ω -	1111 x100 x = Not relevant
Working range	0.0 to 999.9 °C	0.0 to 500 secs	0.0 to 65.0 Ω

RELEVANCE OF 8 DIGIT NUMBER BLOCK IN DISPLAY FIELD 4

Relevance of 8 digit number block in display field 4
1	2	3	4	5	6	7	8	Specifications of diagnostic conditions
1								O2S heating after TWC switched on
	1							O2S after TWC vaporization point exceeded
		1						HO2S after TWC operationally ready
			1					O2S heating after TWC operationally ready
					1			CYCLE Bit = Diagnosis completed
						0		Diagnosis malfunction free
							0	DTC memory malfunction free

Press -C- button.