42RLE - Service Information: Solenoid: Operation: Solenoids

WARNING: This page is about a different car, the 2008 Dodge Magnum, 2008 Dodge Charger, and 2008 Chrysler 300. However, it is still accessible from the selected car via links, so may be relevant.

When an electrical current is applied to the solenoid coil, a magnetic field is created which produces an attraction to the plunger, causing the plunger to move and work against the spring pressure and the load applied by the fluid the valve is controlling. The plunger is normally directly attached to the valve which it is to operate. When the current is removed from the coil, the attraction is removed and the plunger will return to its original position due to spring pressure.

The plunger is made of a conductive material and accomplishes this movement by providing a path for the magnetic field to flow. By keeping the air gap between the plunger and the coil to the minimum necessary to allow free movement of the plunger, the magnetic field is maximized.