Pcm Code E13, Oxygen (O2) Sensor Not Ready: Action

PCM turns on SERVICE ENGINE SOON light and disables "closed loop".

NOTE: Test numbers refer to numbers on diagnostic chart.

A voltage display of .42-.48 volt is a reference from PCM. O2 sensor must generate a voltage of .15 volt greater or less than .45-volt reference to register O2 sensor cross count in PCM.
PCM compares voltage on circuit No. 412 to ground voltage on circuit No. 413. O2 sensor ground and PCM ground on pin E15 must be at same voltage potential with engine running.