A4 Sedan V6-3.2L (BKH) (2007)
Oxygen Sensor: Testing and Inspection
Heated Oxygen Sensors Before Catalytic Converter, Checking
Heated Oxygen Sensors before Catalytic Converter, Checking
This procedure is used to diagnose Heated Oxygen Sensor (HO2S) (G39) or Heated Oxygen Sensor (HO2S) 2 (G108).
‹› Use only gold-plated terminals when servicing terminals in the electrical harness connector of the Heated Oxygen Sensor (HO2S).
Special tools, testers and auxiliary items required
‹› Multimeter.
‹› Wiring diagram.
Test requirements
‹› The Heated Oxygen Sensor (HO2S) (G39) fuse OK.
‹› The Heated Oxygen Sensor (HO2S) 2 (G108) fuse OK.
‹› Battery voltage at least 12.5 volts.
‹› All electrical consumers such as, lights and rear window defroster, switched off.
‹› A/C switched off.
‹› Ground (GND) connections between engine/transmission/chassis OK.
‹› Exhaust system between catalytic converter and cylinder head properly sealed.
‹› Coolant Temperature at least 80° C.
Function test
Perform a function test of the Heated Oxygen Sensors (HO2S). Refer to ADD LINK
If specified values are obtained:
-
End diagnosis and switch the ignition off.
If the specified values are not obtained:
Test procedure
-
Perform a preliminary check to verify the customers complaint. Refer to => [ General Diagnosis ] See: Testing and Inspection/Initial Inspection
and Diagnostic Overview/General Diagnosis.
Start diagnosis
-
Disconnect the Heated Oxygen Sensor (HO2S) (G39 ) electrical harness connector - 1 -.