P0135 - 2002 Accord SE
 

Error Code from OBD II:
P0135
Oxygen Sensor Heater
Bank 1 Sensor 1

Is this the O2 sensor that is up front visible with the hood open, or is the one from under the car?

Thanks

4-cyl engine??

Yes, it's the one in front. Unplug it & find the 2 same-color wires on the sensor side of the plug. Measure resistance between those. For a non-ULEV engine that should be 10 to 40 ohms. A bad sensor will usually be open-circuit.

For a ULEV engine, the correct resistance might be different but I don't know what it should be.

If that measurement is OK, then you'll have to troubleshoot wiring problems in the car.