How to test if an H02S 02 sensor heater element has failed.
Find the 2 wires with the same color.
Set multi meter to Ohms.
Use Ohms to measure resistance.
The Ohms should be 3-25 or the O2 sensor is bad and has failed.
Read Here for more information. https://www.backyardmechanic.org/what-is-an-engine-o2-sensor/