heater AUDI A4 1995 B5 / 1.G APB Engine Oxygen Sensor Control Checking Workshop Manual
[x] Cancel search | Manufacturer: AUDI, Model Year: 1995, Model line: A4, Model: AUDI A4 1995 B5 / 1.GPages: 61, PDF Size: 0.27 MB
Page 2 of 61
24-80
If the voltage does not change or only changes
slowly the following malfunctions are possible:
Slits or holes in probe head are blocked.
Oxygen sensor has been subjected to
excessive thermal stress.
Contact resistance in signal wire or Ground
(GND) wire.
Oxygen sensor too cold; sensor heater not
working.
Oxygen sensor damaged by contact spray or
similar product. (The contact spray is drawn
through the fine cavities in the electrical wiring
as a result of thermal fluctuations and capillary
effect.)
Oxygen sensor damaged by silicone vapors.
(The engine draws in traces of any silicone-
based sealants that may have been used. The
silicone does not burn and damages the oxygen
sensor.)
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Page 7 of 61
24-85
Significance of 3 digit indication in Display Group 30 1
1
1
Display fields 1 through 3
X Oxygen sensor control
0= inactive
1= active
X Operational readiness of oxygen sensor
0= inactive
1= active
X Condition of oxygen sensor heater
0= inactive
1= active
Note:
The oxygen sensor control for oxygen sensors behind the catalytic converter (B1-S2 and B2-S2) are without engine load
at certain operating conditions not active, that means, the third place of oxygen sensor control for oxygen sensors behind
the catalytic converter can fluctuate between 0 and 1.
The first position of the 3 digit display (Heater) fluctuate at certain operating conditions between 0 and 1.
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Page 11 of 61
24-89
If the specified values in display fields 1
and/or 3 do not match the specifications, or if
the readout does not fluctuate by at least 2
%:
- Check oxygen sensor heater Page 24
-114
.
- Check oxygen sensor signal wire and activation
Page 24
-122
.
- Check intake system for leaks and eliminate
false air Page 24
-76
.
- Check fuel pressure regulator Page 24
-33
.
- Fuel return line kinked or plugged.
-
Press button.
- Press button -0- and -6- to select function "End
Output" and confirm with -Q- button.
- Switch ignition off.
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Page 13 of 61
24-91
Evaluation display group 032 Display Group 32
Display fields: 1/3
Possible cause
Corrective action
Oxygen sensor adaptation
values in range:
4.0 and 25.0 %
Un-metered air in intake area- Check intake system for un-metered
air and eliminate leaks
Display field: 2/4
Fuel pressure too low- Check fuel pressure regulator Page
24
-33
Oxygen sensor adaptation
values in range:
4.0 - 25.0 %
Oxygen sensor heater faulty- Check oxygen sensor heater Page
24
-114
Injector not opening or only opening partially - Check injectors Page 24
-39
EVAP canister purge regulator valve remains
in stuck in open position - Check EVAP canister purge
regulator valve Page 24
-134
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Page 14 of 61
24-92
Evaluation display group 33 Display Group
33
Display field:
2/4
Possible cause
Corrective action
Approx. 0.450
V
Open circuit in wire 4 between oxygen sensor and
control module - Check signal wire and activation Page 24
-
122
Open circuit in wire 3 between oxygen sensor and
control module
Oxygen sensor heater faulty
Oxygen sensor faulty- Check oxygen sensor heater Page 24
-114
- Replace oxygen sensor
More than
1.100 V
Short to B+ in wire 4 between oxygen sensor and
control module - Check oxygen sensor wiring, bank 1, sensor
1 Page 24
-123
Less than
0.100 V
Short to Ground (GND) in wire 4 between oxygen
sensor and control module - Check oxygen sensor wiring, bank 2, sensor
1 Page 24
-127
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Page 27 of 61
24-104
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 1, sensor 2 Oxygen sensor status,
bank 2, sensor 1 Oxygen sensor status
bank 2, sensor 2
Working
area 0 = off
1 = on 0 = off
1 = on 0 = off
1 = on 0 = off
1 = on
Specified
value: 1 1 1
1 1 1 1 1 1
1 1 1
Note:
Significance of display Page 24
-105
If specified value is not obtained:
Check oxygen sensor signal wire and activation Page 24
-122
Check oxygen sensor heater Page 24
-114
Notes:
Oxygen sensor control of oxygen sensor behind catalytic converter (Bank 1-Sensor 2 and Bank 2 -Sensor 2) is not active
without engine load.
The first position of the 3 digit indication (heater) fluctuates between 0 and 1.
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Page 29 of 61
24-105
Significance of 3 digit indication in Display Group 030 1
1
1
Display fields 1 to 4
X Oxygen sensor control
0= inactive
1= active
X Operational readiness of oxygen sensor
0= inactive
1= active
X Condition of oxygen sensor heater
0= inactive
1= active
- Press -C- button.Basic Setting
Q
Input displa
y group number XXX
When indicated on display
Test requirements - Press buttons -0-, -4- and -3- to select "display group number 043" and press -Q-
button to confirm input.
Engine runs at 1900 - 2200 RPM
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Page 31 of 61
24-106
Display fields
1 2 3
4
Display group 043: Oxygen sensor aging oxygen sensor behind catalytic converter (Bank 1)
Display xxxx/RPM
xxx C
x.xxx V
Test ON
Indicated Engine speed
(RPM) Exhaust
temperature Voltage of oxygen sensor
behind CAT, Bank 1 Diagnostic condition
Work range 0 - 6800/RPM
70 - 850 C
0.000 - 1.000 Volt
Test OFF
Test ON
B1-S2 OK
B1-S2 not OK
Specified
value 1900 -
2200/RPM greater than 320
C 0.000 - 1.000 Volt
B1-S2 OK
Note
If specified value is not reached. Check
oxygen sensor heater Page 24
-114
If the specified value of "B1-S2 OK" is reached:
- Press -C- button.
Test requirements
Engine runs at 1900 - 2200 RPM
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Page 33 of 61
24-107
Display fields
1 2 3
4
Display group 044: Oxygen sensor aging oxygen sensor behind catalytic converter (Bank 2)
Display xxxx/RPM
xxx C
x.xxx V
Test ON
Indicated Engine speed
(RPM) Exhaust
temperature Voltage of oxygen sensor
behind CAT, Bank 1 Diagnostic condition
Work range 0 - 6800/RPM
70 - 850 C
0.000 - 1.000 Volt
Test OFF
Test ON
B2-S2 OK
B2-S2 not OK
Specified
value 1900 -
2200/RPM greater than 320
C 0.000 - 1.000 Volt
B1-S2 OK
Note
If specified value is not reached. Check
oxygen sensor heater Page 24
-114
If the specified value of "B2-S2 OK" is reached:
- Press -C- button.
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Page 40 of 61
24-112
Evaluation display group 037 and 038 Display Group:
037/038
Display field: 2
Possible cause
Corrective action
approx.: 0.450 V
Open circuit in wire 4 between oxygen sensor
and control module - Check signal wire and activation Page 24
-
122
Open circuit in wire 3 between oxygen sensor
and control module
Oxygen sensor heater faulty
Oxygen sensor faulty- Check oxygen sensor heater Page 24
-114
- Replace oxygen sensor
greater than
1.100 V
Short circuit to B+ in wire 4 between oxygen
sensor and control module - Check oxygen sensor wiring bank 1 sensor 2
(behind converter) Page 24
-125
smaller than
0.100 V
Short circuit to Ground (GND) in wire 4 between
oxygen sensor and control module
Short circuit between wire 3 and 4- Check oxygen sensor wiring bank 2 sensor 2
(behind converter) Page 24
-129
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