Started car after two week absence. Engine malfunction light came on. DTCs are P0141 and P0161.

P0141 HO2S-12 (Bank 1 Sensor 2) Heater Circuit Malfunction
P0161 HO2S-22 (Bank 2 Sensor 2) Heater Circuit Malfunction

ohmmeter showed open heater element on Bank 1 Sensor 2 so I replaced it with Denso O2 sensor.
Bank 2 Sensor 2 ohmmeter reading was 6.6 ohms so did not replace it.

Still getting both P0141 and P0161 after clearing DTCs with scan tool.

1st issue with the Accord in 162,000 miles that I haven't been able to resolve myself. :-) Help!

Any suggestions?



P0141HO2S-12 (Bank 1 Sensor 2) Heater Circuit Malfunction P0161HO2S-22 (Bank 2 Sensor 2) Heater Circuit Malfunction

 

You may want to check your fuse(s). Dont have the shop manual on this computer.

 

Thanks! I found this link http://www.mediafire.com/?8mqpeanbmh7hp9k
It listed under dash fuse 18 for the 2003 model year as possible culprit.
Fuse 18 - ELD unit, Secondary HO2S, Alternator, Cruise control unit, CAM sensor, Engine mount control solenoid (A/T)
Will be checking this tomorrow.

 

Fuses are all ok. Voltages are what they should be on the O2 sensor connector. Troubleshooting next steps suggest three possibilities at this point. 1. Open between PCM E21 and Sensor. 2. PCM update if it does not have latest software (Has not changed in 162,000 miles. 3. PCM replacement.
One correction in my original post. The replacement sensor was an NGK and not Denso. Not sure it matters. It was identical to the one I removed.

Thanks

 

Problem turned out to be defective ECU 37820-RCA-L96. I removed ECU and opened it up and found a burnt resistor. The risistor took out a couple of etch paths and without schematic I was not going to attempt repair. Found a replacement on Ebay. East Park Auto Recycling for $94.00 and paid dealership $98.00 to reflash. Thanks to all for suggestions.

 

Thank you coming back with the "end of the story", too many times these end up as dead ends and no one ever knows what happened.