Commander 4WD V8-4.7L VIN N (2006)
Windshield Washer Pump: Description and Operation
PUMP-WASHER-WINDSHIELD
DESCRIPTION
The washer pump/motor unit (3) is located on the outboard side of the washer reservoir, in the left front fender wheel house ahead of the front wheel and
the left front wheel house splash shield. A small permanently lubricated and sealed reversible electric motor is coupled to the rotor-type washer pump
(4). The use of an integral valve body (6) allows the washer pump/ motor unit to provide washer fluid to either the front or the rear washer systems,
depending upon the direction of the pump impeller rotation.
A seal flange with a barbed inlet nipple (8) on the pump housing passes through a rubber grommet seal installed in a dedicated mounting hole of the
washer reservoir. A removable molded plastic filter screen (9) inserted into the inlet nipple prevents most debris from entering the pump housing. When
the pump is installed in the reservoir the front barbed outlet nipple (5) on the pump valve body housing connects the unit to the front washer hose, and
the rear barbed outlet nipple (7) connects the unit to the rear washer hose. The letters F and R molded into the valve body housing adjacent to each
nipple provide further clarification of the nipple assignments.
The washer pump/motor unit is retained on the reservoir by the interference fit between the barbed pump inlet nipple and the grommet seal, which is a
light press fit. The top of the washer pump is also secured to the washer reservoir by the use of a snap post (1) on the motor and a snap post receptacle
molded into the reservoir that allows for mounting of the washer pump without the use of fasteners. An integral connector receptacle (2) on the top of the
motor housing connects the unit to the vehicle electrical system through a dedicated take out and connector of the headlamp and dash wire harness.
The washer pump/motor unit cannot be repaired. If ineffective or damaged, the entire unit must be replaced.
OPERATION
The washer pump/motor unit features a reversible electric motor. The direction of the motor is controlled by hard wired outputs from the Front Control
Module (FCM). When battery current and ground are applied to the two pump motor terminals, the motor rotates in one direction. When the polarity of
these connections is reversed, the motor rotates in the opposite direction. When the pump motor is energized, the rotor-type pump pressurizes the washer
fluid and forces it through one of the two pump outlet nipples, and into the front or rear washer plumbing.
