DTC P1245: Intake Plenum Switchover Valve: Description

The intake plenum switchover valve is a long moveable divider inside the intake manifold, which changes induction airflow characteristics as it pivots above a certain engine speed/load range. The ECM controls the intake plenum switchover valve by controlling the intake plenum switchover solenoid. The intake plenum switchover solenoid is supplied continuous ported vacuum, which is transferred to the intake plenum switchover diaphragms whenever the solenoid is energized. The ECM controls the solenoid by supplying the circuit ground. When the solenoid is commanded off (circuit not grounded), the voltage level at the ECM should be high (ignition voltage). When the solenoid is commanded on (circuit grounded), the voltage level at the ECM should be low. DTC P1245 will set if the ECM detects lower than normal feedback voltage when the intake plenum switchover solenoid is commanded off; or higher than normal feedback voltage when the intake plenum switchover solenoid is commanded on.