DanDombrowski
12-21-2005, 12:46 PM
Is anyone familiar with the heater circuit in an o2 sensor?
Its that time of year where my car sits in the garage and I take my Dad's Mitsu Eclipse for a month for repairs, maintenance, road testing, etc. I've been throwing the check engine code P0141 repeatedly. Got underneath the car, found the sensor covered in oil (from leaking VC gaskets). Fixed the gaskets, cleaned all the oil off the sensor (outside), cleaned the connection at the wiring harness, and reset the codes. The code stayed off for about 10 cycles, then came back on. Got under the car, sensor was still dry.
So, the P0141 code refers to the O2 sensor heater circuit. The O2 sensor itself is reading just fine. So my question is....how does the heater circuit function?
Its a 3 wire sensor, and I've been told that the ECU measures the resistance of the heater circuit. One wire for O2 reading, one wire for heater, and the third one ground? Or is it more complicated than that? My guess is that there is a broken wire somewhere in the O2 sensor wire causing this problem (because it worked when I cleaned stuff and moved wires around), and then went back again. Tried wiggling wires around again, no luck. I'm hesitant to replace a $175 O2 sensor if I can fix a broken wire on it, especially since the o2 sensor is giving voltages in the same range as the Bank 2 sensor.
Thanks guys, sorry for the OT post, but I figured that its a pretty universal question and a resolution might help us out in the future.
Its that time of year where my car sits in the garage and I take my Dad's Mitsu Eclipse for a month for repairs, maintenance, road testing, etc. I've been throwing the check engine code P0141 repeatedly. Got underneath the car, found the sensor covered in oil (from leaking VC gaskets). Fixed the gaskets, cleaned all the oil off the sensor (outside), cleaned the connection at the wiring harness, and reset the codes. The code stayed off for about 10 cycles, then came back on. Got under the car, sensor was still dry.
So, the P0141 code refers to the O2 sensor heater circuit. The O2 sensor itself is reading just fine. So my question is....how does the heater circuit function?
Its a 3 wire sensor, and I've been told that the ECU measures the resistance of the heater circuit. One wire for O2 reading, one wire for heater, and the third one ground? Or is it more complicated than that? My guess is that there is a broken wire somewhere in the O2 sensor wire causing this problem (because it worked when I cleaned stuff and moved wires around), and then went back again. Tried wiggling wires around again, no luck. I'm hesitant to replace a $175 O2 sensor if I can fix a broken wire on it, especially since the o2 sensor is giving voltages in the same range as the Bank 2 sensor.
Thanks guys, sorry for the OT post, but I figured that its a pretty universal question and a resolution might help us out in the future.