Engine Control Module Self Test Description

The ECM performs a number of self-test integrity diagnostics on its internal hardware and software to check for faults. An error is detected if the ECM receives no CAN messages for at least 0.5 seconds and the calculated checksums at power up/down do not match the values stored in FLASH EPROM. See Fig 1 .

Fig 1: Engine Control Module Self Test Monitoring & Enabling Conditions

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