2000 AUDI A6 check engine

24-96

- Press buttons -0-, -3- and -5- to select "display
group number 035" and press -Q- button to
confirm input. System in Basic Setting 35
1
2
3
4

When indicated on display:
Note:
The test in display group 035 is activated simultaneously with the test in
display group 034 Therefore the test result is indicated immediately after
display group 035 is selected. - Check specified value in display field 4.

Display fields

1 2 3 4
Display group 035: Oxygen sensor aging diagnostic, oxygen sensor before catalytic converter (bank 2)
Display xxxx/min
xxx C
x.x s
---
Indicated Engine speed
(RPM) Exhaust
temperature Period duration
Oxygen sensor before
Catalytic converter Diagnostic condition
Functional
range 630 to 6800
70 to 850 C
0 to 3.0 s
B1-S2 OK
B1-S2 not OK
Specified
value 1000 to 2400
RPM above 380 C 0.1 to 1.8 s B1-S2 OK
Notes


If the specified value is not reached, replace oxygen sensor 2
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24-98

Notes:

The oxygen sensor control behind catalytic
converter overrules the oxygen sensor control
before catalytic converter. It serves as a
corrective control.

Test requirements:
Test sequence
It corrects slight changes in the mixture (i.e. enrichment) via the
oxygen sensor before catalytic converter by holding oxygen sensor
control before catalytic converter at its higher or lower point for a
specific time (dwell time). If this time is in the positive range (i.e. 50
ms), mixture is shifted in the -enrich- direction. If it is in the negative
range (i.e.--50 ms), mixture is shifted in the -lean- direction. Road test performed and DTC memory erased. Coolant temperature at least 80 C Display group 4, display field 3
- Connect VAS5051 tester or VAG1551 scan tool and select the control
module for engine electronics using "address word" 01 Page 01
-9 .
Engine must run at idle for this.
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24-99

Rapid data transfer
HELP
Select function XX

When indicated on display:
Note:
During basic setting, the Evaporative Emission (EVAP) canister purge
regulator valve (EVAP valve -N80-) is closed and the A/C compressor is
switched off - Press buttons -0- and -4- to select "Initiate basic setting" and press -Q-
button to confirm input.
Basic Settin
g
Q
Input displa
y group number XXX

When indicated on display:
- Press buttons -0-, -3- and -4- to select "display group number 034" and
press -Q- button to confirm input.
System in Basic Setting 34
1
2
3
4

When indicated on display:
Note:
This process can take a few minutes. - Use VAG1788/10 RPM adjuster to adjust engine speed to between
2800 and 3200 RPM.
- Continue test as soon as display field 2 indicates an exhaust
temperature of more than 380 C
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24-100

- Press -C- button.

- Let engine continue to idle Basic Setting
Q
Input displa
y group number XXX

When indicated on display:
- Press buttons -0-, -3- and -0- to select "display group number 030" and
press -Q- button to confirm input.
System in Basic Setting 30
1
2
3
4

When indicated on display:
Note:
"Oxygen sensor status" indicates status of oxygen sensor control and
oxygen sensors. - Check oxygen sensor status for oxygen sensor behind catalytic
converter in display fields 2 and 4.
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24-101


Display fields

1 2 3 4
Display group 030: Oxygen sensor status with engine at idle
Display X X X
X X X X X X
X X X
Indicated Oxygen sensor status, bank 1,
sensor 1 Oxygen sensor
status
Bank 2, sensor 1 Oxygen sensor status, bank 2,
sensor 1 Oxygen sensor
status
Bank 2, sensor 2
Functional
range 0 = off
1 = on 0 = off
1 = on 0 = off
1 = on 0 = off
1 = on
Specified
value 1 1 1
1 1 0 1 1 1
1 1 0
Notes
Meaning of display Page 24
-102

If specified value is not obtained Page 24
-111

If specified value is obtained but there is a malfunction stored in DTC memory Check oxygen
sensor control, page Page 24
-105

Notes:

Oxygen sensor control of oxygen sensor behind catalytic converter (bank 1 sensor 2 and bank 2 sensor 2) are not active
without engine load, meaning that the display is 0.
The first position of the 3 digit indication (heating) fluctuates between 0 and 1.
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24-103


Display fields

1 2 3 4
Display group 043: Oxygen sensor aging, oxygen sensor behind catalytic converter (bank 1)
Display xxxx/min
xxx C
x.xxx V
---
Indicated Engine speed
(RPM) Exhaust
temperature Voltage of oxygen sensor
behind catalytic converter,
bank 1 Diagnostic condition
Functional
range 630 to 6800
RPM 70 to 850 C
0.100 to 1.000 volts Test OFF
Test ON
B1-S2 OK
B1-S2 not OK
Specified
value 1800 to 2400
RPM above 380 C 0.100 to 1.000 volts B1-S2 OK
Notes



If specified value is not obtained
Check oxygen sensor heater Page
24
-116

If specified value B1-S2 OK" is obtained:

- Press -C- button.

- Press buttons -0-, -4- and -4- to select "display
group number 044" and press -Q- button to
confirm input.
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24-104


Display fields

1 2 3 4
Display group 044: Oxygen sensor aging, oxygen sensor behind catalytic converter (bank 2)
Display xxxx/min
xxx C
x.xxx V
---
Indicated Engine speed
(RPM) Exhaust
temperature Voltage of oxygen sensor
behind catalytic converter,
bank 2 Diagnostic condition
Functional
range 670 to 6800
RPM 70 to 850 C
0.100 to 1.000 volts Test OFF
Test ON
B2-S2 OK
B2-S2 not OK
Specified
value 1800 to 2400
RPM above 380 C 0.100 to 1.000 volts B2-S2 OK
Notes



If specified value is not obtained
Check oxygen sensor heater Page
24
-116

If specified value B2-S2 OK" is obtained:

- Press -C- button.
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24-105

Checking oxygen sensor control behind
catalytic converter

- Perform a test drive of approx. 10 minutes.

WARNING!

Observe safety precautions to reduce the risk
of accidents during road test Page 24
-1 .

- Let engine continue to run at idle.Basic Setting
Q
Input displa
y group number XXX

When indicated on display:
- Press buttons -0-, -3- and -7- to select "display group number 037" and
press -Q- button to confirm input.
System in Basic Setting 37
1
2
3
4

When indicated on display:
- Check oxygen sensor voltage in display field 2.
- Check dwell time between oxygen sensor 1 before catalytic converter
and oxygen sensor 2 behind catalytic converter in display field 3 and
diagnostic result in display field 4.
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p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
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pair&id=AUDI.B5.FU05.24.3