Auto Headlamp Relay; Door Ajar Switch; Door Lock Cylinder Switch; Horn Relay - Jeep 1997 Grand Cherokee Service Manual

8Q - 4 VEHICLE THEFT/SECURITY SYSTEMS
DESCRIPTION AND OPERATION (Continued)

DOOR AJAR SWITCH

The door ajar switches are mounted to the pillar in
the rear of each door opening. They are plunger-type
switches that are case grounded to the pillar. When
the door is open the switch is closed, and when the
door is closed the switch is open.
The door ajar switches cannot be repaired and, if
faulty or damaged, they must be replaced.

DOOR LOCK CYLINDER SWITCH

The door lock cylinder switches are mounted to the
back of the key lock cylinder inside each front door.
They are normally-open momentary switches that
close to ground only when the lock cylinder is rotated
to the unlock position.
The door lock cylinder switches cannot be repaired
and, if faulty or damaged, they must be replaced.

LIFTGATE AJAR SWITCH

The liftgate ajar switch is integral to the liftgate
latch assembly on the liftgate. It is a momentary-
type switch that is open when the liftgate is closed,
and closed when the liftgate is open.
The liftgate ajar switch cannot be repaired and, if
faulty or damaged, the liftgate latch assembly must
be replaced.

LIFTGATE LOCK CYLINDER SWITCH

The liftgate lock cylinder switch is mounted to the
back of the key lock cylinder inside the liftgate. It is
a normally-open momentary switch that closes to
ground only when the lock cylinder is rotated to the
unlock position.
The liftgate lock cylinder switch cannot be repaired
and, if faulty or damaged, it must be replaced.

LIFTGLASS AJAR SWITCH

The liftglass ajar switch is integral to the liftglass
latch assembly on the liftgate. It is a momentary-
type switch that is open when the liftglass is closed,
and closed when the liftglass is open.
The liftglass ajar switch cannot be repaired and, if
faulty or damaged, the liftglass latch assembly must
be replaced.

AUTO HEADLAMP RELAY

The auto headlamp relay is a International Stan-
dards Organization (ISO) micro-relay. The terminal
designations and functions are the same as a conven-
tional ISO relay. However, the micro-relay terminal
orientation (or footprint) is different, current capacity
is lower, and the relay case dimensions are smaller
than those of the conventional ISO relay.
The auto headlamp relay is a electromechanical
device that switches battery current to the head-
lamps when the Body Control Module (BCM) grounds
the relay coil. See the Diagnosis and Testing section
of this group for more information on the operation of
the auto headlamp relay.
The auto headlamp relay is located in the junction
block, on the right cowl side panel below the instru-
ment panel in the passenger compartment.
The auto headlamp relay cannot be repaired and, if
faulty or damaged, it must be replaced.

HORN RELAY

The horn relay is a International Standards Orga-
nization (ISO) micro-relay. The terminal designations
and functions are the same as a conventional ISO
relay. However, the micro-relay terminal orientation
(or footprint) is different, current capacity is lower,
and the relay case dimensions are smaller than those
of the conventional ISO relay.
The horn relay is a electromechanical device that
switches battery current to the horns when the horn
switch or the Body Control Module (BCM) grounds
the relay coil. See the Diagnosis and Testing section
of this group for more information on the operation of
the horn relay.
The horn relay is located in the Power Distribution
Center (PDC), in the engine compartment. Refer to
the PDC label for relay identification and location.
If a problem is encountered with a continuously
sounding horn, it can usually be quickly resolved by
removing the horn relay from PDC until further
diagnosis is completed.
The horn relay cannot be repaired and, if faulty or
damaged, it must be replaced.

PARK LAMP RELAY

The park lamp relay is a International Standards
Organization (ISO) micro-relay. The terminal desig-
nations and functions are the same as a conventional
ISO relay. However, the micro-relay terminal orienta-
tion (or footprint) is different, current capacity is
lower, and the relay case dimensions are smaller
than those of the conventional ISO relay.
The park lamp relay is a electromechanical device
that switches battery current to the park lamps
when the Body Control Module grounds the relay
coil. See the Diagnosis and Testing section of this
group for more inbformation on the operation of the
park lamp relay.
The park lamp relay is located in the junction
block, on the right cowl side panel below the instru-
ment panel in the passenger compartment. The park
lamp relay can be accessed by removing the fuse
access panel and the right cowl side trim panel.
The park lamp relay cannot be repaired and, if
faulty or damaged, it must be replaced.
ZG