Check Engine Light on with “O2 Sensor Heater Circuit Malfunction (Bank 1 Sensor 1)”

[Vox]

Hi there,

I have Honda Civic 97 CX automatic with 80K on it. The check engine light started going orange all the time when my car is running. I got OBD2 car reader and got the following error message: “O2 Sensor Heater Circuit Malfunction (Bank 1 Sensor 1)”.

What does it mean?
Is it safe to drive my car while this CEL is on?
How big deal is to replace this sensor (should it be replaced) and how much it costs?

Thanks,

Vox

[RonJ]

If you tell me the code number, I will look it up in my service manual and tell you what it recommends.

[RonJ]

Is the code below the one you are reading:

P0135 - Primary Heated Oxygen Sensor Heater Circuit Malfunction
(Sensor 1) -- An electrical problem in the Primary Heated Oxygen Sensor (Primary HO2S) (Sensor1) Heater system {Except D16Y5 engine( M/T)}.

If so, the possible problems are:

1) Open or short in Primary HO2S
(Sensor 1) heater circuit
2) ECM

The attached picture shows location of O2 sensor and how to remove it.

[Vox]

It is the P0135 code, I just double checked.
Any idea what is part # I should get and where to get it from?

Thanks and sorry, I am not very "hands on" when it comes to cars

[RonJ]

The trouble code alone does not identify the defective part (see two attached Troubleshooting flowchart pages). As shown in the flowchart, the problem could be the O2 sensor, wiring between the sensor and the ECM (computer), or the ECM. If you don't know how to perform the tests indicated in the flowchart, you may need to take your car to a trusted mechanic. Perhaps experts on this site could give you additional advice.