1996 AUDI A4 sensor

24-79
Display group 032 Display field: 1 / 2
Possible cause
Corrective action
Oxygen sensor adaptation
values via specified range
False air in intake area- Check intake system for leaks and repair
false air Page 24
-68


Fuel pressure too low- Check fuel pressure regulator Page 24
-32

Mass Air Flow (MAF) sensor faulty- Mass Air Flow (MAF) sensor, checking
Page 24
-59


Oxygen sensor heating faultyOxygen sensor faulty- Check oxygen sensor heating Page 24
-89

Fuel injector does not open or opens
only partially - Check fuel injectors Page 24
-37
.

Evaporative Emission (EVAP)
Canister Purge Regulator Valve sticks - Check Evaporative Emission (EVAP)
canister purge regulator valve Page 24
-114

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Evaluation display group 033 Display field:
2
Possible cause
Corrective action
larger than
4.800 V
Short circuit to B+ in wire connections between
oxygen sensor and control module
Oxygen sensor faulty- Check oxygen sensor wires of oxygen sensor
before catalytic converter Page 24
-82

smaller than
0.130 V
Short circuit to Ground (GND) in wire connections
between oxygen sensor and control module
Oxygen sensor faulty
- Replace oxygen sensor before catalytic
converter
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Checking primary voltage

Note:
Coolant reservoir screws must be removed and coolant reservoir must be
placed to side in order to access the harness connector. The coolant
hoses can remain connected. - Disconnect 6-pin harness connector (black) -2- to Heated Oxygen
Sensor (HO2S) -G39- before catalytic converter.

- Connect multimeter between terminal 1 and 5 for voltage
measurement.
- Switch ignition on.

Specification: 0.400 to 0.500 V
- Switch ignition off.
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If specified value is not obtained:

- Check oxygen sensor wiring.
If specified value is obtained:

- Replace Heated Oxygen Sensor (HO2S)-G39-
.

Checking oxygen sensor wires

Note:
Coolant reservoir screws must be removed and coolant reservoir must be
placed to side in order to access the harness connector. The coolant
hoses can remain connected. - Disconnect 6-pin harness connector (black) -2- to Heated Oxygen
Sensor (HO2S) -G39- before catalytic converter.
- Connect VAG1598/31 test box at wiring harness to Engine Control
Module (ECM), do not connect ECM Page 24
-19
.
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Electrical Wiring Diagrams, Troubleshooting & Component Locations
If wire connection is OK: - Check the following wire connections for open circuit.Harness connector
Terminal
VAG1598/31 test box
Socket
1 70
2 71
5 51
6 52
- Repair open circuit if necessary.- Check wires to each other for short circuit.
- Replace Engine Control Module (ECM) Page 24
-22
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Oxygen sensor aging, oxygen sensor
before catalytic converter, checking


Special Tools and Equipment

VAG1788/10 RPM adjuster

Test requirement:
VAS5051 with VAG5051/1Coolant Temperature at least 80 C.
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Test sequence

- Connect VAS5051 tester Page 01
-7 and
select vehicle system "01 - Engine electronics".
Engine must run at idle for this.

Display on VAS5051:
- In selection -1-, click on the diagnostic function "04 - Basic setting".
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Display on VAS5051:
1 - Enter display group Max. input value = 255
- Select function "034" in button field -2- for "display group number 034"
and press Q button to confirm input.
- Use VAG1788/10 RPM adjuster to adjust engine speed to between
2300 and 2800 RPM.

Display on VAS5051:
Note:
This process can take a few minutes. - Check specified value in display field -4-.
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play?action=Goto&t
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pair&id=AUDI.B5.FU07.24.2