VTEC System - VTEC Lock Control Solenoid Valve

PROCEDURE


A malfunction of the VTEC solenoid valve causes a diagnostic trouble code to be stored in the PCM memory and the Check Engine light to illuminate (refer to Engine Control Section).

The most common cause of VTEC malfunction is a faulty solenoid valve or its filter. Performing regular engine oil and oil filter changes will help prevent unwanted failures.

1. The VTEC lock control solenoid valve is located on top of the oil filter housing (at the rear of the right side of the power unit) and is best viewed through the right front wheel arch.

2. Disconnect the VTEC solenoid valve wiring connector. Measure the resistance between the connector terminal and ground. The specified value is 14 - 30 ohms. If not within specification, replace the VTEC solenoid valve.

3. With the ignition OFF, disconnect the wiring harness connector from the VTEC oil pressure switch and check for continuity between the two switch terminals on the VTEC solenoid valve. Continuity must be present; otherwise, replace the oil pressure switch.

4. Turn the ignition ON and measure the voltage between the blue/black wire terminal of the oil pressure switch connector and ground. The required value is approximately 12 V. If not, check the wire between the connector and the PCM for an open circuit or short to ground.

5. Turn the ignition OFF and check for continuity between the brown/black wire terminal of the oil pressure switch connector and ground. If there is no continuity, check the brown/black wire for an open circuit between the connector and the ground point.

6. Remove the VTEC solenoid valve and check the plunger for free movement by hand. When installing the valve, be sure to replace the gasket.

7. Remove the oil filter adapter housing from the engine block. Check the oil filter element for blockage and inspect the condition of the gasket.

A blocked strainer screen is the most likely cause of VTEC system malfunction.