Troubleshooting

DTC P0018 Crankshaft Position - Camshaft Position Correlation (Bank 2 Sensor A)

CIRCUIT DESCRIPTION

DTC Detection Condition:

Camshaft position sensor (G (VV) signal) consists of a magnet, iron core and pickup coil.The G (VV) signal plate has 3 teeth, on its outer circumference and is installed 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 camshaft position sensor and it provides feedback to the ECM to control the intake valve timing in response to driving condition.

MONITOR DESCRIPTION

Monitor Strategy:

Typical Enabling Conditions:

Typical Malfunction Thresholds:

The ECM optimizes the valve timing using the Variable Valve Timing (VVT) system to control the intake valve camshaft. The VVT system includes the ECM, the Oil Control Valve (OCV) and the VVT controller. The ECM sends a target duty-cycle control signal to the OCV. This control signal, applied to the OCV, regulates the oil pressure supplied to the VVT controller. The VVT controller can advance or retard the intake valve camshaft. The ECM calibrates the valve timing of the VVT system by setting the camshaft to the maximum retard angle when the engine speed is idling. The ECM closes the OCV to retard the cam. The ECM stores this valve as VVT learned value (When the difference between the target valve timing and the actual valve timing is 5 degrees or less, the ECM stores this in its memory).

If the learned value meets both of the following conditions ("a" and "b"), the ECM interprets this as a defect in the VVT system and sets a DTC.
a. VVT learning value is less than 20 °CA or more than 46 °CA.
b. Above condition continues for more than 18 second.

Wiring Diagram:

Step 1:

INSPECTION PROCEDURE

HINT: Read freeze frame data using OBD II scan tool or hand-held tester. Because freeze frame records the engine conditions when the malfunction is detected. When troubleshooting, it is useful for determining whether the vehicle was running or stopped, the engine was warmed up or not, the air-fuel ratio was lean or rich, etc. at the time of the malfunction.