Emission codes
 

Forgive me if this has been asked before, I don't do searches well. My Girlfriends '03 Accord has the Malfunction light on. Scanned it at Auto Zone. The code is P0141. Heated Oxygen sensor- Bank 1 Sensor 2. This could also be a short circuit or a connection problem. I'm assuming this is a sensor on the catalytic converter somewheres.
How do I properly test the wiring for faults and are any fuses involved?
If the O2 sensor needs to be replaced, can I get this anywhere or OEM only? This should be a fairly easy repair once I know what I'm looking for.

Gary

Test the sensor first. The sensor is bolted into the catalytic converter (or just past the converter). I think that the wire goes through the floor board and the electrical connector is under either the driver's or passenger's seat. Follow the wire to figure out where the connector is located.

Once you find the connector, unplug it, and measure the resistance across the pins of the sensor that have the same wire color. There should be about 10 ohms resistance. The circuit should not read infinite resistance (open circuit). If the circuit is open, replace the sensor. I would go with a Denso sensor, because they make the Honda OEM sensors.

Seems to me beginning in 2003 the heater resistance is lower, so the proper resistance might be closer to 5 ohms. Still, they normally fail to open-circuit.

Thanks guys, I'll get to this after the drveway is cleared of freshly fallen global warming.
Gary

How does the wiring disconnect from the sensor? I took a quick look and it doesn't seem to pull straight off. And is there a special tool needed to replace the sensor? Looks like a large deep well socket will work.

A few inches away from the sensor there should be a connector. That is why there is an O2 Sensor socket, it has a cutout on it so it can get around the wires. Many places rent them out, not that expensive if you wanted to buy one. You might check some online sites, they should show a picture of the sensor-give you an idea of the length of the leads, at the same time show you the price of an O2 socket.

The wire doesn't come off the sensor. Follow the wire. Not sure, but I think I remember the wire goes through the floorpan. If so, the plug is located under the passenger seat.

Here is more information if necessary, some is a repeat of what was said by others. This is for the 4 cylinder. If yours is a V6, let me know.

1. Pull back the carpet from the floor rail under the front edge of the front passenger seat to expose the secondary HO2S 4P connector.

Disconnect the secondary HO2S 4P connector (A).


2. Remove the secondary HO2S (A), and the covers (B).

Install the secondary HO2S in the reverse order of removal.