2009 Aveo down stream O2 sensor fuse location

[Brian Howden]

I have a 2009 Aveo with 50K miles on it. I got a DTC of P0036 / P0138 / P0141 which all point to the heater circuit of the downstream O2 sensor. An ohm meter showed open on all combinations of the 4 pins so I bought a new NTK sensor with the correct plug on it and installed it. A few minutes later I am getting a P0054 which looks like a variation of the heater circuit for the down stream O2 sensor. Google has not been a lot of help other than check the fuse but I have not been able to find a location for the correct fuse.

Does anybody have any suggestions for where the fuse is located or other things I should be checking? Thanks in advance.

Brian

[Brian Howden]

Hmmm. No ideas? Any suggestions on how to go about trouble shooting a P0054? Anything else to check?

Brian

[Brian Howden]

So I have a little more information. I used an ohm meter to check the new sensor and it shows about 4 ohms across 2 pins on one side of the connector which I assume is the heater. I went back and checked the same two pins on the old sensor and they show as open. The car side of the connector shows about 8 volts across these two pins. I get 12 volts across two diagonal pins but there is infinite resistance across those pins on the sensor. This indicates to me that any fuses are fine. An OBDII reader app on my phone shows the O2 and heater circuits are not in a state of readiness and gives no reading for them. A bit more googling indicates that some ECM's have to be calibrated to a new heater. (or be put into a calibration mode).

Any idea if the Aveo falls into this category? If so, how do I do this?

Brian

[Brian Howden]

Figured I better answer my own question in case anybody else is searching for the same problem. Short answer is that the replacement turned out to be the wrong sensor. The car is registered as a 2009. The VIN number checks out as a 2009. The GM dealer looked up the Delco part number for that VIN and it cross references to the NTK sensor I used. My brother in law was looking at pictures online and noticed that the retainer clip for the wire on my original was the same colour as the NTK for 2007-8. I checked the manufacture date on the door panel and it was May 2008 so if it is a 2009 it is a very early one. On spec I tried the NTK sensor for 2007-8 and it cured the problem. It has been over a week and there are no codes and no pending codes. Glad I wasn't paying the dealer hourly rates to fix this one!

Brian