scknight

I live in an apartment building and so over the winter my 97 maxima se manual had been out in the cold all season. My check engine light came on during the winter and the code was 0902, which my chilton says is "Downstream oxygen sensor heater or circuit fault" Now i had hoped this was due to my car sitting outside all winter, and didnt worry about fixing it right away because it was only the downstream sensor. So now that its nicer out id like to fix this problem. I basically need to know how to check for exactly whats wrong. I know where the downstream oxygen sensor is but i dont want to have to replace it if i dont have to. So does anyone have any advice on how to go about checking the specific problem that it could be? Now if i had of gotten code 0707 which is just downstream oxygen sensor fault, i probally woulda just tried to test the oxygen sensor like the haynes manual says and replace it if its bad. But this is 0902 and the downstream oxygen sensor heater and im not exactly sure if thats part of the sensor or the heater is a seperate part and i couldnt find it in my haynes manual. Thanks for the help, and I apolgize if this messsage is a little incoherant, im a little tired.

Thanks,
Scott

philly96maxima

The Heater is part of the o2 sensor.
Since the downstream sensor does not effect the fuel system operation I would just clear the code and see if the same code comes back.

scknight

Yeah I already did that in the winter and it came back, and then i did it again today sine weather is warmer and again it came back. So if its part of the sensor, i can probally just run through the tests in the haynes manual. It looks like im gonna have to replae the sensor though. Any idea how much a new sensor costs?

philly96maxima

If you do not mind reusing the original connectors , you can get them for about $39.00 from oxygensensors.com.

I bought two front sensors from them,,I spoke to them, they are manufactured by Denso, I just resoldered the original connectors back on and then used heat shrink tubing which comes with the sensors.
If you want them with the connectors already on they are $25 .oo more each..so if your not afraid to solder its a big savings. these tjings cost about $80 each elseware and like $117 each at dealers.