Location of Wiper Relay in Grand Cherokee 2000 V8-47L VIN N
Wiper Relay: Description and Operation
WIPER HIGH/LOW RELAY
The wiper high/low relay is a electromechanical device that switches battery current from the wiper motor low speed coil windings to the high
speed coil windings when the wiper and washer (right multi-function) switch grounds the relay coil. The wiper high/low relay is located in the
Power Distribution Center (PDC) in the engine compartment. See the fuse and relay layout label affixed to the inside surface of the PDC cover for
wiper high/low relay identification and location.
The wiper high/low relay is a International Standards Organization (ISO) micro-relay. Relays conforming to the ISO specifications have common
physical dimensions, current capacities, terminal patterns, and terminal functions. The ISO micro-relay terminal functions are the same as a
conventional ISO relay. However, the ISO micro-relay terminal pattern (or footprint) is different, the current capacity is lower, and the physical
dimensions are smaller than those of the conventional ISO relay.
The wiper high/low relay cannot be repaired or adjusted and, if faulty or damaged, it must be replaced.
The ISO relay consists of an electromagnetic coil, a resistor or diode, and three (two fixed and one movable) electrical contacts. The movable
(common feed) relay contact is held against one of the fixed contacts (normally closed) by spring pressure. When the electromagnetic coil is
energized, it draws the movable contact away from the normally closed fixed contact, and holds it against the other (normally open) fixed contact.
When the electromagnetic coil is de-energized, spring pressure returns the movable contact to the normally closed position.The resistor or diode is
connected in parallel with the electromagnetic coil in the relay, and helps to dissipate voltage spikes that are produced when the coil is
de-energized.
WIPER ON/OFF RELAY
The wiper on/off relay is a electromechanical device that switches battery current to the wiper high/low relay when the Body Control Module (
BCM) grounds the relay coil. The wiper on/off relay is located in the Power Distribution Center (PDC) in the engine compartment. See the fuse
and relay layout label affixed to the inside surface of the PDC cover for wiper on/off relay identification and location.
The wiper on/off relay is a International Standards Organization (ISO) micro-relay. Relays conforming to the ISO specifications have common
physical dimensions, current capacities, terminal patterns, and terminal functions. The ISO micro-relay terminal functions are the same as a
conventional ISO relay. However, the ISO micro-relay terminal pattern (or footprint) is different, the current capacity is lower, and the physical
dimensions are smaller than those of the conventional ISO relay.
The wiper on/off relay cannot be repaired or adjusted and, if faulty or damaged, it must be replaced.
The ISO relay consists of an electromagnetic coil, a resistor or diode, and three (two fixed and one movable) electrical contacts. The movable
(common feed) relay contact is held against one of the fixed contacts (normally closed) by spring pressure. When the electromagnetic coil is
energized, it draws the movable contact away from the normally closed fixed contact, and holds it against the other (normally open) fixed contact.
When the electromagnetic coil is de-energized, spring pressure returns the movable contact to the normally closed position. The resistor or diode is
connected in parallel with the electromagnetic coil in the relay, and helps to dissipate voltage spikes that are produced when the coil is
de-energized.
