Circuit Description

PCM monitors 5 volt reference signal when ignition is on. If PCM senses an Analog To Digital (A/D) conversion error within PCM, DTC P1627 will be set.

When DTC sets, PCM will illuminate MIL as soon as fault is detected. PCM will store conditions present when DTC set as failure records data and in FAILURE RECORDS.

PCM will turn MIL off on third consecutive trip cycle during which diagnostic runs and fault is no longer recognized. A history DTC will clear after 40 consecutive trip cycles during which diagnostic runs and fault is no longer recognized. DTC can be cleared with scan tool, or by disconnecting battery voltage feed to PCM.