lock AUDI A4 1997 B5 / 1.G AFC Engine Oxygen Sensor Control Checking Before Converter Workshop Manual

24-45


Oxygen Sensor (O2S) control,
checking (before three way
catalytic converter)

Note:

G39 = Heated Oxygen Sensor (HO2S), bank
1
G108 = Heated Oxygen Sensor (HO2S) 2, bank
2

- Read measuring value block using VAG 1551
scan tool until display shows "Read measuring
value block 1" (display group 001) Repair
Group 01.
Read measuring value block 1 1 2 3 4

Indicated on display
Note:
Continue with the test only if the value in display field 1 (engine coolant
temperature) is at least 80 C (176 F). - Press -C- button.
- Press buttons -0-, -1- and -0- to input display group 010.
- Press -Q- button to confirm input.
Read measuring value block 10

Indicated on display
Pa
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en Sensor
(O2S
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11/22/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
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pair&id=AUDI.B5.FU01.24.11

24-46
If a constant sensor voltage of 0.000V is
displayed, there is a short to Ground (GND).

- Check DTC memory Repair Group 01. If sensor voltage is constant between 0.350 and
0.450 volts, the signal is interrupted:

- Check DTC memory page 01
-13
.
If sensor voltage is a constant 2.550 volts, there
is a short to battery positive voltage (B+):

- Check DTC memory page 01
-13
.

- If sensor voltage is a constant 0.0 to 0.3 volts,
the oxygen sensor measures a lean mixture:

- Check DTC memory page 01
-13
.

- If sensor voltage is a constant 0.6 to 0.9 volts,
the oxygen sensor measures a rich mixture:

- Check DTC memory page 01
-13
.

- Press -C- button.Read measuring value block
Q

- Indicated on display
Pa
ge 3 of 7 Ox
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en Sensor
(O2S
) control, checkin
g (before three wa
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ytic converter
)
11/22/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
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pair&id=AUDI.B5.FU01.24.11

24-48

- Press buttons -0-, -0- and -5- to input display
group number 005 for bank 1, or press buttons -
0-, -0- and -6- to input display group number 006
for bank 2.

- Press -Q- button to confirm input.Read measuring value block 5 -4.6% 0.7% 0 % 0 %

Indicated on display (example)
Note:
If necessary, display group 005 (bank 1) or 006 (bank 2) for
troubleshooting can be read using "Basic Setting" function 04 and then
printed out page 01
-150
, Basic Setting. By selecting this function
(among other things) the evaporative emissions factor is not included.
Pa
ge 7 of 7 Ox
yg
en Sensor
(O2S
) control, checkin
g (before three wa
y catal
ytic converter
)
11/22/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU01.24.11