Oxygen sensor light on check panel on

[smtguy]

Previous owner removed the oxygen sensor indicator light from the check panel, I guess because it was always on. I decided to change the O2 sensor to see if that would cancel the light, but no luck - it is on from the time the key is turned to the engine starting and running. Is there a reset for this? It seems to be electrical as opposed to the light being on because the sensor is bad. I would appreciate any ideas or suggestions here. This all started because the car is currently not passing smog.

[bobinyelm]

I would guess since the O2 sensor is new, it's working properly (though you could check via a millvoltmeter while the engine is running, of course).

Another question in view of the fact you failed smog would be if the O2 sensor is working, is the signal getting to the ECU? You could do a pin-out to check the continuity of the leads from the O2 sensor to the actual ECU plug to find that out.

Did they fail you because of a sniffer-test, or because you had what they saw as a "Check Engine Light?" Many states will fail you even if you have a light because of an AC failure. To many, a light is a light.

An M30 engine can be tuned w/ NO O2 sensor or Cat to pass smog (unless it's a dyno test in some cases), assuming they don't do a thorough visual check, though in the cases of my Alpinas (which were gray market cars that had no O2 sensors, or Cats at all), I'm not sure what would constitute a visual check (since they were Federalized enough to be let in, but which were not fully compliant or identical to US cars*). Ask me how I know that.

Does it run perfectly smoothly? After all this time, an AFM calibration could help things. Simple to remove the cover and adjust the static position of the spring pressure.

Bob

*They made me take OUT the First Aid Kit, and replace the headlights with US Spec units, and in one case install a useless side guard beam in the front doors, yet left many Euro items intact.

[smtguy]

Thanks for the comments. I did not have the bulb or the new 02 sensor in when I had the smog pre-check done, so not they did not see the 02 sensor light illuminated.

Are you aware of any reset? for this?

Thanks