1995 AUDI A4 sensor

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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System in Basic Setting 44
1
2
3
4

When indicated on display:
- Check specified value in display field 4 after indication "Test ON"
appears:
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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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p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
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e=re
pair&id=AUDI.B5.FU05.24.3

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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pair&id=AUDI.B5.FU05.24.3

24-106


Display fields

1 2 3 4
Display group 037: Diagnostic, oxygen sensor control system (bank 1)
Display xxx % x.xxx volts
xxx ms
---
Indicated Engine
load Oxygen sensor voltage
behind catalytic
converter, bank 1 Oxygen sensor correction
value between oxygen sensor
1 and oxygen sensor 2, bank 1 Diagnostic condition
Functional
range 12.0 to
100.0 % 0.100 to 1.000 V
-800 to 800 ms
Test OFF
Test ON
System OK
System not OK
Specified
value 12.0 to
26.0 % 0.100 to 1.000 V
-800 to 800 ms System OK
Notes
If specified value is not
obtained: Evaluation
display field 2
Page 24
-109

If specified value is not
obtained Page 24
-110

If "System not OK" is displayed:
Check Diagnostic Trouble Code
(DTC) memory Page 01
-15

or continuation Page 24
-110

Note for display field 3:
The oxygen sensor control behind catalytic converter overrules the oxygen sensor control before catalytic converter. It
corrects slight changes in the mixture (i.e. toward rich or lean) due to 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 this time is in the negative range (i.e. -50 ms), mixture
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pair&id=AUDI.B5.FU05.24.3

is shifted in the -lean- direction.
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24-107

- Press -C- button.

- Press buttons -0-, -3- and -8- to select "display
group number 038" and press -Q- button to
confirm input. System in Basic Setting 38
1
2
3
4

When indicated on display:
Note:
The test in display group 038 is activated simultaneously with the test in
display group 037 Therefore the test result is indicated immediately after
display group 038 is selected. - Check specified value 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

24-108


Display fields

1 2 3 4
Display group 038: Diagnostic of oxygen sensor control system (Bank 2)
Display xxx % x.xxx V xxx ms
---
Indicated Engine
load Oxygen sensor voltage
behind catalytic converter,
bank 2 Oxygen sensor correction
value between oxygen sensor
2 and oxygen sensor 2, bank
1 Diagnostic condition
Functional
range 12.0 to
100.0 % 0.100 to 1.000 V -800 to 800 ms
System OK
System not OK
Specified
value 12.0 to
26.0 % 0.100 to 1.000 V -800 to 800 ms System OK
Notes
If specified value is not
obtained: Evaluation
display field 2 Page 24
-
109

If specified value is not
obtained Page 24
-110

If "SYST not OK" is displayed:
Check Diagnostic Trouble Code
(DTC) memory Page 01
-15

or continuation
Page 24
-110

Note for display field 3:
The oxygen sensor control behind catalytic converter overrules the oxygen sensor control before catalytic converter. It
corrects slight changes in the mixture (i.e. toward rich or lean) due to 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 this time is in the negative range (i.e. -50 ms), mixture
is shifted in the -lean- direction.
Pa
ge 40 of 63 Ox
yg
en sensor control, checkin
g
11/23/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU05.24.3