1997 AUDI A4 lock

24-91
If specified value is obtained:

- Check voltage supply of oxygen sensor
heating.

Checking voltage supply for oxygen sensor
heating

Note:
When the Engine Control Module (ECM) switches oxygen sensor heating
on and off, it may be observed via the function "read measuring value
block", in display group number 041 display field 2.
If there is no voltage: - Connect multimeter between terminal 3 and 4 for voltage
measurement.
- Start engine.

Specification: approx. battery voltage

- Connect multimeter for voltage measurement as follows.Harness connector
Terminal
Measure to
3 (B+) Vehicle Ground (GND)
Pa
ge 22 of 46 Ox
yg
en sensor control, checkin
g
11/22/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU07.24.2

When the Engine Control Module (ECM) switches oxygen sensor heating
on and off, it may be observed via the function "read measuring value
block", in display group number 041 display field 2.
Pa
ge 24 of 46 Ox
yg
en sensor control, checkin
g
11/22/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU07.24.2

24-109
If specified value is obtained:

- Check voltage supply of oxygen sensor
heating.

Checking voltage supply for oxygen sensor
heating

Note:
When the Engine Control Module (ECM) switches oxygen sensor heating
on and off, it may be observed via the function "read measuring value
block", in display group number 041 display field 4.
If there is no voltage: - Connect multimeter between terminal 1 (B+) and 2 (Ground -GND-) for
voltage measurement.
- Start engine.

Specification: approx. battery voltage

- Connect multimeter for voltage measurement as follows:Harness connector
Terminal
Measure to
1 (B+) Vehicle Ground (GND)
Pa
ge 42 of 46 Ox
yg
en sensor control, checkin
g
11/22/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU07.24.2

24-112

Oxygen sensor, removing and installing


Special tools and equipment

Procedure
3337 wrench, 7-piece set Locking compound G 052 112 A3

Note:
Coolant reservoir screws must be removed and coolant reservoir must be
placed to side in order to access harness connectors. The coolant hoses
can remain connected. - Disconnect oxygen sensor harness connector and lay to side.
1 - (brown) for Oxygen Sensor (O2S) behind Three Way Catalytic
Converter (TWC) -G130-
2 - (black) for Heated Oxygen Sensor (HO2S) -G39- before catalytic
converter
- Unscrew oxygen sensor using special tool 3337.
Pa
ge 45 of 46 Ox
yg
en sensor control, checkin
g
11/22/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU07.24.2