Supercharger Air Control Valve: Description and Operation

SCB VALVE CONTROL SOLENOID VALVE

SYSTEM DESCRIPTION

System Description:

This system controls supercharged air according to the engine operating conditions.

This control operation is accomplished through the ECM and the SCB valve control solenoid valve.

When the solenoid valve is ON, the SCB valve shuts. Then intake air is lead to supercharger, and supercharged air is sent to the cylinder.




When the solenoid valve is OFF, the SCB valve opens. Then intake air is sent to the cylinder directly. When the ECM detects any of the following conditions, current does not flow through the solenoid valve.
- Engine stopped
- Engine starting
- High-load, high-speed engine operation
- Excessively low engine coolant temperature
- Mass air flow sensor malfunction
- Engine coolant temperature sensor malfunction
- Throttle position sensor malfunction

COMPONENT DESCRIPTION




SCB Valve Control Solenoid Valve
The SCB valve control solenoid valve responds to signals from the ECM.
When the ECM sends an OFF signal, the solenoid valve is bypassed to apply intake manifold vacuum to the SCB valve actuator. This operation opens the SCB valve. When the ECM sends ON (ground) signal, the SCB valve opens or closes depend on the throttle valve position, regarding to the pressure difference between atmosphere and throttle body.