1999 AUDI A4 APB Engine Motronic Syst

The Engine Control Module (ECM) cycles at certain operating conditions the oxygen sensor heating, that means, the
heater is certain operating conditions ON or OFF. It is therefore possible that the specification in display field 2 and 4
appears periodically as "Heater b. CAT OFF" or "Heater a. CAT OFF"

- Press -C- button.
Pa
ge 145 of 166 Motronic s
ystem, On Board Dia
gnostic
(OBD
)
11/22/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU04.01.1

01-120

Work step 8: Diagnosis oxygen sensor aging
before catalytic converter

Test requirements

Engine running at 1900 - 2200 RPM
System in Basic Settin
g
Q
Input display group number XXX

Indicated on display
- Press buttons -0-, -3- and -4- to select "display group number 034" and
confirm with -Q- button.
System in Basic Setting 34
1
2
3
4

Indicated on display
- Check specified value in display field 4:
Pa
ge 146 of 166 Motronic s
ystem, On Board Dia
gnostic
(OBD
)
11/22/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU04.01.1

01-121


Display fields

1 2 3 4
Display group 034: Oxygen sensor aging before catalytic converter (bank 1)
Display xxxx/RPM
xxx C
x.x seconds
Test ON
Indicated Engine speed
(RPM) Exhaust
temperature Period duration of oxygen
sensor before CAT Diagnostic condition
Work range 0 - 6800/RPM
70 - 850 C
0.0 - 3.0 Seconds
Test OFF
Test ON
B1-S1 OK
B1-S1 not OK
Specified
value 1900 -
2200/RPM Greater than 260
C 0.1 - 1.0 Seconds
B1-S1 OK
Note



If "B1-S1 not OK" is displayed: Check
DTC memory Page 01
-15
.
If specified value of "B1-S1 OK" is reached:

- Press -C- button.

Test requirements

Engine running at 1900 - 2200 RPM
Pa
ge 147 of 166 Motronic s
ystem, On Board Dia
gnostic
(OBD
)
11/22/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU04.01.1

- Press buttons -0-, -3- and -5- to select "display
group number 035" and confirm with -Q- button.
Pa
ge 148 of 166 Motronic s
ystem, On Board Dia
gnostic
(OBD
)
11/22/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU04.01.1

01-122


Display fields

1 2 3 4
Display group 035: Oxygen sensor aging before catalytic converter (Bank 2)
Display xxxx/RPM
xxx C
x.x seconds
Test ON
Indicated Engine speed
(RPM) Exhaust
temperature Period duration of
oxygen sensor
before TWC Diagnostic condition
Work range 0 - 6800/RPM
70 - 850 C
0.0 - 3.0 Seconds
Test OFF
Test ON
B2-S1 OK
B2-S1 not OK
Specified
value 1900 -
2200/RPM greater than 260
C 0.1 - 1.0 Seconds
B2-S1 OK
Note



IF "B2-S1 not OK" is displayed: Check DTC
memory Page 01
-15
.
If specified value of "B2-S1 OK" is reached:

- Press -C- button.
Pa
ge 149 of 166 Motronic s
ystem, On Board Dia
gnostic
(OBD
)
11/22/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU04.01.1

01-123

Work step 9: Diagnosis of operational
readiness of oxygen sensors behind TWC

Test requirements

Engine at idle
System in Basic Settin
g
Q
Input display group number XXX

Indicated on Display
- Press buttons -0-, -3- and -6- to select "display group number 036" and
press -Q- button to confirm input.
System in Basic Setting 36
1
2
3
4

Indicated on display
- Check specified values in display fields 2 and 4.
Pa
ge 150 of 166 Motronic s
ystem, On Board Dia
gnostic
(OBD
)
11/22/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU04.01.1

01-124


Display fields

1 2 3 4
Display group 036: Operational readiness of oxygen sensors behind TWC (Bank 1 and Bank 2)
Display x.xxx Volt
Test ON x.xxx Volt
Test ON
Indicated Voltage of
oxygen
sensor behind
TWC, bank 1 Diagnostic condition Voltage of
oxygen
sensor behind
TWC, bank 2 Diagnostic condition
Work
range 0.000V - 1.000
Volt Test OFF
Test ON
B1-S2 OK
B1-S2 not OK 0.000V -
1.000Volt Test OFF
Test ON
B2-S2 OK
B2-S2 not OK
Value less than 0.4
Volt or
greater than 0.5
Volt B1-S2 OK less than 0.4 Volt
or
greater than 0.5
Volt B2-S2 OK
Note

IF "B1-S2 not OK" is displayed:
Check DTC Memory Page 01
-
15
.

If "B2-S2 not OK" is displayed:
Check DTC memory Page 01
-
15
.
If the specified value in display field 2 "B1-S2
OK" and in display field 4 "B2-S2 OK" is
reached:
Pa
ge 151 of 166 Motronic s
ystem, On Board Dia
gnostic
(OBD
)
11/22/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU04.01.1

- Press -C- button.
Pa
ge 152 of 166 Motronic s
ystem, On Board Dia
gnostic
(OBD
)
11/22/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU04.01.1