P0134 O2 sensor ckt no activity(bank 1 sensor 1)?

B.PEDRO.A

MEMBER
2003 CHEVROLET CAVALIER

I have replaced the O2 sensor twice now. Both times I still get the check engine lite. I know that the O2 works but the obd code says the o2 circuit is inactive.

did a fuse go or something? At my wits end on this one.

again here are the obd codes.

p0134 o2 sensor ckt no activity(bank 1 sensor 1)

p0130 o2 sensor circuit malfunction(bank 1 sensor 1)

p0135 o2 sensor heater circuit malfunction(bank 1 sensor 1)

again this is the second new o2 sensor I have installed. (The o2 sensor nearer to the motor.)

thanks

1 Reply

SQM

MECHANIC
6,383 POSTS

Hello,

These codes are likely due to a faulty circuit/harness for the oxygen sensor.
As you have already changed the oxygen sensor, you know that is not the root cause of the issue.

To pinpoint what is the real issue you will have to take a step-by-step approach and look at a few different items.
I have attached the trouble shooting steps for the code P0134 below. All these codes are related to one another. So, solving one should take care of the others.
Follow these steps and that can help determine the real issue.

You will need a multimeter to perform these steps.

https://www.2carpros.com/articles/how-to-use-a-voltmeter

Please let me know if you have any questions.
Thank you.

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