I have a 2006 Honda Accord with the 2.4L 4-cylinder engine.

Recently the check engine light came on and I had it scanned. The result was that there was a P0141 Fault, which is a "fault in the Bank 1, Sensor 2 02 Heater electrical circuit for a predetermined length of time", A second scan also said oxygen sensor, number two.

Looking under the car it appears to have two oxygen sensors - one just beyond the manifold and another that appears to be in the catalytic converter. Taking a shot and based on a conversation with the auto store clerk (yeah, I know) I replaced the one in the cat. Restarting the car the light is still on. I haven't done anything to clear the codes though. I used a Bosch O2 sensor that has the kit to splice the wire to the original sensor plug.

Here are my questions:
1) How long will it take for the light to go out, assuming the issue is corrected?
2) Does this type of setup have a good track record or should I have just soldered the wires? Is there a way to verify that I am getting a good connection at this point? Is there a sensor that comes with the plug attached?
3) Did I get the right sensor based on the code scan? Is there even a way to know this?
4) Is this a thing where if one goes you may as well replace both?

Thanks in advance. I assume this is the right place for this post. If it is not, mods please move this.

Thanks again.

 

Sensor 2 is the one in the Cat. It's job is to just monitor the cat. Personally I would have used a Denso O2 sensor, as the Bosch units aren't really as good. You shouldn't need to replace both sensors.
You should have the codes cleared, as they won't do it themselves. You'll have to ask someone on here to tell you how to do that without a scanner, as I'm not familiar with what it takes (some models just require removing a certain fuse for 15 to 20 seconds). I normally use my scan tool to clear codes.

 

2003 & newer won't clear by pulling a fuse or a battery cable. That's when they started using non-volatile memory.

That said, the error should clear itself after a short while. I don't know how long it takes.

But that error code can also be caused by a break in the wiring of the car, for that heater circuit. I've always used the sensor with the proper plug, no splicing; so I don't know much about the track record. What you CAN do is check to see if you get the proper power at the plug. Someone around here probably has a pin-out for the 2nd O2 sensor.

 

Suggest disconnecting secondary (post-cat) O2 sensor and checking for 12V and ground on the harness side of connection (pins 3 & 4) w/ a test light. See step 11. Power (12v) should be available w/ key On at pin 4. Ground should be available on pin 3.

If either is missing, a wiring , fuse, connector fault, or ECM fault exists.

If both ground and power are present, bad O2 sensor (probably mis-wired).

You could have a fault in the O2 sensor signal and signal ground wires (pins 1 & 2). This would present a different code. You should re-scan to check. Again mis-wiring is likely.

good luck

 

 

MIL light will go out if the problem is fixed. It can take several drive cycles (start-run-shutdown) to go out.

If MIL (check engine) light remains on, codes should be scanned at an auto parts store. I have read they will not reset the ECM (turn MIL off), but may differ by state.

good luck

 

Yes, I've heard that in some states most auto parts places won't clear codes. Harbor Freight sells code readers, and it might be worth buying one if you plan on working on this car. I have an Actron that I use at home, and it's become invaluable.