P0604

CIRCUIT DESCRIPTION
The ECM performs an internal self-test on the Random Access Memory (RAM) or the read/write memory.

CONDITIONS FOR RUNNING THE DTC
Engine cranking

CONDITIONS FOR SETTING THE DTC
The internal RAM test fails.

ACTION TAKEN WHEN THE DTC SETS
The ECM illuminates the Malfunction Indicator Lamp (MIL) and records the operating conditions in the Freeze Frame on the first drive trip that the diagnostic runs and fails.

Diagnostic Chart:

CONDITIONS FOR CLEARING THE MIL/DTC
^ The ECM turns OFF the MIL after three consecutive drive trips that the diagnostic runs and passes.
^ A History DTC clears after forty consecutive warm-up cycles in which no failures are reported by this diagnostic or any other emission related diagnostic.
^ The scan tool clears the MIL/DTC.