Page 9 of 63
24-83
Checking oxygen sensor adaptation values
and control
- Press -C- button.Basic Setting
Q
Input displa
y group number XXX
When indicated on display:
- Press buttons -0-, -3- and -3- to select "display group number 033" and
press -Q- button to confirm input.
System in Basic Setting 33
1
2
3
4
When indicated on display:
- Check oxygen sensor control in display fields 1 and 3.
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Page 10 of 63
24-84
1 2 3 4
Display group 033: Oxygen sensor control before catalytic converter
Display
xx.x % x.xxx volts
xx.x % x.xxx V
Indicated
Oxygen sensor control
Bank1 Oxygen sensor voltage
bank 1 Oxygen sensor control
Bank2 Oxygen sensor voltage
bank 2
Functional
range -25.0 to 25.0 % 0.100 to 1.000 V
-25.0 to 25.0 % 0.100 to 1.000 V
Specified
value Value must fluctuate by
at least 2 % in the range
10.0 to 10.0 % Value must fluctuate
approx. 0.3 V in the
range 0.100 to 1.000
volts Value must fluctuate by
at least 2 % in the range
10.0 to 10.0 % Value must fluctuate
approx. 0.3 V in the
range 0.100 to 1.000
volts
Notes
If specified value is not
obtained Page 24
-85
If specified value is not
obtained Page 24
-85
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Page 11 of 63
24-85
Evaluation display group 033 Display field: 1 / 3
Possible cause
Corrective action
Values in range:
-10.0 to -25.0 %
Oxygen sensor heating faulty- Check oxygen sensor heating Page
24
-116
or
Values in range:
Open circuit in wires between oxygen sensor
and control module - Check primary voltage Page 24
-89
10.0 to 25.0 %
or
Value does not fluctuate
by at least 2 %
Short circuit to Ground (GND) or B+ between
oxygen sensor and control module - Check oxygen sensor wires bank 1
Page 24
-90
- Check oxygen sensor wires bank 2
Page 24
-91
False air in intake area- Check intake system for leaks and
repair false air Page 24
-64
Fuel pressure too low or too high- Check fuel pressure regulator Page
24
-30
Fuel return line is kinked or clogged- Check fuel return line.
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Page 12 of 63

24-86
- Press -C- button.
- Press buttons -0-, -3- and -2- to select "display
group number 032" and press -Q- button to
confirm input. System in Basic Setting 32
1
2
3
4
When indicated on display:
- Check oxygen sensor control in display fields 1 to 4:
Display fields
1 2 3 4
Display group 032: Oxygen sensor adaptation values before catalytic converter
Display
xx.x %
xx.x %
xx.x %
xx.x %
Indicated
Oxygen sensor
adaptation value
Bank 1 at idle
(additive) Oxygen sensor adaptation
value bank 1 at partial
throttle
(multiple) Oxygen sensor
adaptation value
Bank 2 at idle
(additive) Oxygen sensor adaptation
value bank 2 at partial
throttle
(multiple)
Functional
range -25.0 to 25.0 %
-25.0 to 25.0 %
-25.0 to 25.0 %
-25.0 to 25.0 %
Specified
value -10.0 to 10.0 %
can fluctuate
slightly -10.0 to 10.0 %
can fluctuate slightly -10.0 to 10.0 %
can fluctuate
slightly -10.0 to 10.0 %
can fluctuate slightly
Notes
If specified value is not obtained Page 24
-87
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Page 13 of 63
24-87
Evaluation display group 032 Display field:
1 / 3 or 2 / 4
Possible cause
Corrective action
Oxygen sensor
adaptation value in
range:
-10.0 to .-25.0 %
Oil thinning- Oil change or perform swift country road
test
High oil consumption
Mass Air Flow (MAF) sensor faulty- Mass Air Flow (MAF) sensor, checking
Page 24
-56
Evaporative Emission (EVAP) canister purge
regulator valve remains stuck in open position - Check Evaporative Emission (EVAP)
Canister Purge Regulator Valve Page 24
-
128
Fuel pressure too high- Check fuel pressure regulator Page 24
-
30
Fuel return line is kinked or clogged.- Check fuel return line.
Fuel injector does not close- Check fuel injectors Page 24
-36Pa
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Page 14 of 63
24-88
Evaluation display group 032 Display field:
1 / 3 or 2 / 4
Possible cause
Corrective action
Oxygen sensor
adaptation value in range:
10.0 to 25.0 %
False air in intake area- Check intake system for leaks and repair false
air.
Page 24
-64
.
Fuel pressure too low- Check fuel pressure regulator Page 24
-30
Mass Air Flow (MAF) sensor faulty- Mass Air Flow (MAF) sensor, checking
Page 24
-56
Oxygen sensor heating faulty
Oxygen sensor faulty- Check oxygen sensor heating Page 24
-116
Fuel injector does not open or opens
only partially - Check fuel injectors Page 24
-36
Evaporative Emission (EVAP) Canister
Purge Regulator Valve sticks - Check Evaporative Emission (EVAP) Canister
Purge Regulator Valve Page 24
-128
Ignition coil or spark plug faulty- Check ignition coils Page 28
-7
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Page 15 of 63
24-89
Checking primary voltage
Component location of harness connectors
Overview of component locations, page Page
24
-5
Note:
Coolant reservoir screws must be removed and
coolant reservoir must be placed to side in order
to access this harness connector. The coolant
hoses can remain connected.
Test requirement:
Fuse for oxygen sensor are OK
- Disconnect 4-pin harness connector leading to
respective oxygen sensor.
If specified value is not obtained: - Connect multimeter between terminal 3 and 4 for voltage
measurement.
- Switch ignition on.
Specification: 0.400 to 0.500 V
- Switch ignition off.
-
Check oxygen sensor wires Bank 1, page Page 24
-90
or Bank Pa
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Page 16 of 63
2, page Page 24
-91
.
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pair&id=AUDI.B5.FU05.24.3