VTEC/Variable Cylinder Management (VCM): Control
Based on engine speed, vehicle speed, engine load, throttle position, and the engine coolant temperature signal sent from various sensors, the powertrain control module (PCM) determines the ON/OFF of each of the rocker arm oil control solenoids.
The PCM switches low lift, high lift, and 3 cylinder operation by controlling the respective solenoid valves. Hydraulic pressure switches are installed in each solenoid circuit for monitoring system malfunction.
| Mode | PCM sends command to the rocker arm oil control solenoid | Rocker arm oil pressure switch (detected oil pressure) | ||||
|---|---|---|---|---|---|---|
| Solenoid A (Bank 1) |
Solenoid B (Bank 1) |
Solenoid A (Bank 2) |
Switch A (Bank 1) |
Switch B (Bank 1) |
Switch A (Bank 2) |
|
| 6 Cylinder Low Lift | OFF | OFF | OFF | ON (Low) | OFF (Low) | ON (Low) |
| 6 Cylinder High Lift | ON | OFF | ON | OFF (High) | OFF (Low) | OFF (High) |
| 3 Cylinder | OFF | ON | OFF | ON (Low) | ON (High) | ON (Low) |