Monitor Description

The hybrid vehicle control ECU assembly performs many diagnostic tests to verify proper operation of internal ECU systems. In one of these tests, the hybrid vehicle control ECU assembly checks the result of the ECM assembly self-test. If the hybrid vehicle control ECU assembly detects a "Fail" from the ECM assembly self-test, it will conclude that there is an internal malfunction in the ECM assembly and will illuminate the MIL and store a DTC.