I changed the 1st oxygen sensor and it still states that even that one is not working. ?

Hello,
I have a 2001 bmw 325ci and the check engine is on for oxygen sensors. the first o2 sensor has 3 wire power, the second o2 sensor has 2 wires with power, the 3 and 4th oxygen sensors dont have power at all. the car is running good and no issues, but the check engine light is on and i cant pass inspection. I changed the 1st oxygen sensor and it still states that even that one is not working.

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[Nick at Pelican Parts]

The first O2 sensor should not have 3 wires with power but only 2 like the next one. It sounds like the O2 sensor heater wire is not being grounded. You are going to have to check this wire from the O2 sensor to the PCM and make sure it is not broken

- Nick