Circuit Description

WARNING: This page is about a different car, the 2003 Lexus RX 300. However, it is still accessible from the selected car via links, so may be relevant.

NOTE: Variable Valve Timing (VVT) sensor is also known as Camshaft Position (CMP) sensor.

Sensor consists of a magnet, iron core and pickup coil. The signal plate has 3 teeth on its outer circumference, and is installed in the camshaft timing gear. When the camshafts rotate, the protrusion on the signal plate and the air gap on the pickup coil change, causing fluctuations in the magnetic field and generating an electromotive force in the pickup coil. The actual camshaft angle is detected by the sensor and it provides feedback to the ECM to control the intake valve timing in response to driving condition. DTCs are set when no camshaft position sensor signal to ECM during cranking for 4 seconds or more (2 trip detection logic), no sensor (camshaft position sensor) signal to ECM for 5 seconds or more with engine speed 600 RPM or more, and while crankshaft rotates twice, camshaft position sensor will be input to ECM 5 times. Possible causes are:

Open or short in VVT sensor circuit.
Faulty VVT sensor.
Faulty camshaft timing gear.
Faulty ECM.