I have a 2014 C300 sport 4matic W204

Xentry Diagnostics says
I have an error code P003000
that says. " the output for the heater of oxygen sensor 1 (cylinder bank 1) has an electrical fault or open circuit. _

Both LEFT O2 sensors show low temp or about 375C and minimum temp says 400C.

I am not familiar with "heater"
I ASSUME it does not get to correct operating temperature because I have an O2 sensor that is bad.
BUT the wording about the "heater" has me confused.

I dont see any "heater" on an exploded exhaust parts view.

Can someone explain if I need to replace an O2 sensor
OR
keep searching for a "heater"
OR
something else?

Thanks!

 

Oxygen sensors on modern cars have three wires two used for the heating element to pre heat the sensor so that it starts feeding back voltage to the ECU when the engine is still cold.

Once the car warms up the hot gasses keep the sensor at the correct temp to work properly and then I think the heater is turned off after certain on time has been reached.

Sounds like you need to replace the items which entry has listed as faulty.

 

You need to replace oxygen sensor.