Nissan techs needed: B15 code P0037

[whereda40at]

I just picked up a 03 sentra se-r spec-v last week. Not long after getting the car, a SES light came on. Ran a scanner and it came up as, P0037 H02S 1/2 Heater Ckt Low. What excatly does this mean and how do I go about to replace it? I have searched google and such but it just seems like everyone has one opion and others have another. Really like everyone has the problem but never follow up on what they did to resolve it. The car has no mods on it.

I know this is not for sentra's but I do know a lot of tech's on here should know what this means. Thanks in advance!

[TheRealSy90]

Rear 02 Sensor.

- Not a nissan tech. :D

[hektik13]

yup rear 02 sensor google work tho

[whereda40at]

so i replaced the sensor and cleared the code. it was good for about a tank of gas worth then came back on. i said fuck it and left it alone. then after about 700 miles the light went off. 240 miles later it came back on. currently the light is on. Anyone shed some light?

[HPKMotorsports3]

so i replaced the sensor and cleared the code. it was good for about a tank of gas worth then came back on. i said fuck it and left it alone. then after about 700 miles the light went off. 240 miles later it came back on. currently the light is on. Anyone shed some light?

disconnect the bulb lol

[niscur29]

Does said car have an aftermarket header/midpipe with both cats deleted? If so then you have to ghetto sim (02 spacer) it to prevent having that code keep popping up. Had to do it in mine when I ran header back with no cats.

Check b15sentra.net plenty of information on doing it.

[whereda40at]

I do not have any aftermarket parts on the car. I can't just take the bulb out because I have to go emissions. b15sentra.net never has people follow up on what worked and what didn't with their cars.

[chituntang]

My civic had this kind of problem too. You may need to change both o2 sensors. Mine had a cat failure code and since its not clogged or anything and the car drives like crap, I changed the front o2 sensor. Check light came back after 200 miles for front o2 sensor... Switched back to the old front o2 and replace the rear o2 afterward has kept the check engine light from coming back on for the pass 1k miles.

The ecu can detect if a sensor is present or missing. It cannot tell if the sensor is giving foul readings (on its way out). Unless you have a way to test the o2 sensor, I suggest you change both.

[army240]

Actually, that code is for the HEATER circuit of the O2... could be a wiring problem.

The ECU detect that there is not enough voltage going back to the ECU after it goes throught the O2 sensor.

Check the FSM... everything is in there to guide you throught diagnostic...

Frank