VC Output Circuit [10/2015 - ]: Description

The ECM assembly constantly generates 5 V power source voltage from the auxiliary battery voltages supplied to the +B, +B2 (BATT) terminal to operate the microprocessor. The ECM assembly also provides this power source voltage to the sensors through the VC output circuit.

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When the VC circuit is shorted, the microprocessor in the ECM assembly and sensors that are supplied power through the VC circuit are inactivated because the power is not supplied from the VC circuit. When the system is in this condition, it will not start.