Circuit Description

The VVT system controls the intake valve timing properly in response to driving condition. The ECM controls the Oil Control Valve (OCV) to make the intake valve timing properly, and oil pressure controlled with OCV is supplied to the VVT controller, and then VVT controller changes relative position between the camshaft and the crankshaft. See Fig 1. Possible causes are:

• Open or short in OCV circuit.
• Faulty OCV.
• Faulty ECM.

Fig 1: Identifying Camshaft Position Actuator Circuits

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