o2 sensor

[paulbenning]

hi

dose anybody know if it is possable to test a o2 sensor out of the car.

[Brett_jjj]

You can test the sensors heater element resistance,thats about it I think.The sensor needs to be in the car with the engine running above idle,and you just test the sensors voltages by backprobing the sensor wire connectors at the ECU.Also the early type VN,VP,VR (2 wire) 02 sensors werent the heated type.

[Not_An_Abba_Fan]

The sensor needs to be in the car and at operating temperature to be tested correctly.

[VNVacationer]

On VN series 1's, not sure about others, you can check for a circuit from D7 on the ECM to ground.

If you have a decent multimeter you can then check with the ignition on and engine not running and you should see between 350 and 450 millivolts at D7. Then with the engine at operating temperature the voltage should rapidly change at D7 and be anywhere between 10 and 1000millivolts.