A4 Sedan V6-2.8L (AFC) (1996)
If the specified value is not obtained:
-
Eliminate open or short circuit using wiring diagram.
If wiring OK:
-
Replace ECM.
Oxygen sensor heater, checking
NOTE:
-
Z29 = Oxygen Sensor (O2S) heater, bank 1
-
Z30 = Oxygen Sensor (O2S) heater, bank 2
-
For functional check of O2S heater -Z29- or -Z30-.
-
Disconnect heated oxygen sensor harness connector (component locations, refer to "Component Overview - II" See: Fuel Delivery and Air
Induction/Locations ).
-
Switch multimeter (Fluke 83 or equivalent) to 20 volt range and connect between terminals 1 (B+) and 2 (GND).
-
Start engine and let idle.
Specified value: approx. 12 to 14 V
If the specified value is not obtained:
-
Check oxygen sensor heater fuse.
-
Check fuel pump relay See: Fuel Delivery and Air Induction/Fuel Pump/Fuel Pump Relay/Testing and Inspection
-
Check wiring for continuity between terminal 1 and fuse in fuse holder using wiring diagram, if necessary check terminal assignments.
Specified value: max. 1 ohms
-
Check wiring for continuity between terminals 2 and 8 on ECM connector E.
Specified value: max. 1 ohms
-
Check wiring for continuity between terminals 2 and 3 of ECM connector E (O2S heater -Z30-).
Specified value: max. 1 ohms