# 2000 Maxima p0141



## truckgurl (Jun 20, 2011)

I have p0141 code (o2B1S2 heater circuit). After changing the o2 sensor, it came back. Looking at the service manual, I have tested the new sensor and have the correct ohms between pin 2-3 and opens between 1 -2,3,4 and 4-1,2,3 meaning the new sensor is good.

I disconnected the sensor and got battery voltage between pin 3 and ground. Disconnected the ECM and get continuity between 5 on the ESM and pin 2 on the o2 plug.

So it seems all checks good. I reconnected the ESM and checked voltage at pin 5 while driving. It should be 0-1 volt below 3600 rpm and battery voltage over 3600. I always get battery voltage regardless of engine RPM.

I think it is a problem with the computer not supplying the ground for the heater circuit. The computer is never turning on the heater circuit. Anybody have any other ideas? I have heard that these computers can have some issues, but I wanted to get other opinions before sending the computer for repairs.

Thanks, 
Brenda


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## smj999smj (Jan 1, 2006)

Assuming you replaced the correct sensor, it sould seem like your ECM is the problem based on your information.


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## truckgurl (Jun 20, 2011)

Yeah, it's a non California car, I changed the sensor after the cat. Thanks for the opinion, I guess I'll find a place to send the ECM to.

Brenda


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## Jeff (Oct 17, 2002)

Should be the correct one...after the cat.


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