O2 sensor heater circuit fault (code 41)

[willowbrook]

Hi all,

The check engine light of my honda civic 95 LX went out last night. Just checked and its a code 41: Heated oxygen sensor heater circuit.

Now my question is: Is that heater circuit inside O2 sensor? which means I can simply replace the sensor. Or is the heater circuit somewhere else?
I assume its not a serious problem since the O2 sensor is still working, just not being heated fast enough, right?
Where should I start to really trace down the problem?

Thank you!

I found the previous post, but can't understand it. More details please, how to "verify power and ground to the heater circuit at the O2.")

"if its a CA model, there is a relay in the power distribution box that controls the heater circuit, and also a fuse. Simply, you need to verify power and ground to the heater circuit at the O2's, and follow the power until you find the problem.

Since you have 2 O2 heater codes, there is probably a problem leading upto the O2's, BUT, what could have caused that problem is a shorted heater circuit in ONE of the O2's....so you need to also check for resistance on the O2's."

[UncleBob]

As a general rule, when that code comes around, its a bad O2. The heater circuit is either shorted internally or there's an internal break. You can verify power to the circuit and if its good, you know its the O2.

[willowbrook]

Thank you for the reply!
You are right, it is the O2.
Just another quick question, do I need to remove the shroud when removing O2 Sensor? There does not seem to be enough space, how did you guys do it with honda civic 95.