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Pcm Code EO13, Right Oxygen Sensor Not Ready: Action:

PCM turns on SERVICE ENGINE SOON light and closed loop is disabled. When warm, a properly operating oxygen sensor will drive the PCM's .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 under test conditions, when the oxygen sensor does not vary from the cold or not-ready voltage, PCM assumes sensor cannot respond to air/fuel mixture changes and sets a Code EO13.

NOTE: Test numbers refer to test numbers on diagnostic chart.
  1. A voltage of .42-.48 displayed is a reference from the PCM. Oxygen sensor must generate .15 volt greater than the .45 reference voltage to register a cross count in the PCM.
  2. The PCM compares voltage on circuit No. 412 to the ground voltage on circuit No. 413. It is essential oxygen sensor ground and PCM ground on terminal E15 indicate good continuity (no voltage difference), with engine running.
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