Ecu Code P0135

rick71052 · May 1, 2005

OK...I get the "Check Engine Light" and the OBD comes up with a code "P0135" a malfunction in the O2 Sensor Heater Circuit". Is this a circuit with a relay or a fuse that can be repaired or is the "heater" part of the sensor itself? I've replaced the sensor, reset the ECU, and the light came on again after about 30 miles of driving. Am I looking at replacing the ECU next, or am I missing something?

steviej · May 1, 2005

P0135 is specific for the Bank 1 Sensor 1. You have 3 O2 type sensors. Bank 1 Sensor 1 is the one sensor between the exhaust manifold and the catalytic converter that are closest to the firewall.

Did perhaps you change the sensor that is in the exhaust manifold closest to the radiator? If so that is Bank 2 Sensor 1.

search on "sensor" and limit the search to posts by me in the last 6 months. There was an extensive thread with pictures not too long ago with the same dilemna.

Keep in mind that there are other causes that will trip code P0135 by creating an environment that makes the ECU think that the O2 sensor is not functioning.

Did you happen to test the O2 senosr you took out to make sure it was faulty?

steviej