Pcm Code E017, Left Oxygen (O2) Sensor Not Ready: Description

When warm, a properly operating O2 sensor will drive PCM .45-volt reference signal lower (less than .45 volt) to indicate a lean mixture and higher (greater than .45 volt) to indicate a rich mixture. If O2 sensor does not vary from cold or not-ready voltage under test conditions, PCM assumes sensor cannot respond to air/fuel mixture changes and sets a PCM Code E017.