Body Control Module - Jeep 1997 Grand Cherokee Service Manual

ZG
DESCRIPTION AND OPERATION (Continued)
where a nut secures the wiper motor crank arm to
the motor output shaft.
Wiper speed is controlled by current flow to the
proper set of brushes. The wiper motor completes its
wipe cycle when the windshield wiper (multi-func-
tion) switch is turned to the Off position, and parks
the blades in the lowest portion of the wipe pattern.
The windshield wiper motor cannot be repaired. If
faulty or damaged, the entire wiper motor assembly
must be replaced. The motor crank arm and the link-
age and pivots module are available for service.
REAR
The rear wiper motor is secured with two bolts and
nuts to a bracket on the liftgate inner panel, below
the rear glass and behind the liftgate trim panel. The
motor output shaft passes through the liftgate outer
panel where a gasket, bezel, and nut, seal and secure
the unit to the liftgate outer panel. The rear wiper
arm is secured directly to the motor output shaft
with a nut.
The rear wiper motor unit contains integral elec-
tronic controls that provide the following operating
modes:
• Intermittent wipe with a five to eight second
delay between sweeps.
• Continuous fixed-cycle wipe.
• A park mode that operates the wiper motor until
the blade reaches its park position when the rear
wiper switch or ignition switch is placed in the Off
position, or when the liftgate or liftglass (if the vehi-
cle is so equipped) is opened.
• A rear washer mode that provides two or three
wiper blade sweeps before returning to the previously
selected rear wiper switch mode.
The rear wiper motor cannot be repaired. If faulty
or damaged, the entire rear wiper motor assembly
must be replaced.
WIPER SWITCH AND WASHER SWITCH
FRONT
The windshield wiper and washer switches are
contained in the multi-function switch assembly (Fig.
1). The multi-function switch assembly is secured to
the left side of the steering column.
The multi-function switch contains circuitry for the
following functions:
• Turn signals
• Hazard warning
• Headlamp beam selection
• Headlamp optical horn
• Windshield wipers
• Windshield washers.
The information contained in this group addresses
only the switch functions for the windshield wiper
and washer systems. For information relative to the
WINDSHIELD WASHER BUT- WINDSHIELD WIPER CON- TON TROL
WIPER AND WASHER SYSTEMS
other switch functions, refer to the proper group.
However, the multi-function
repaired. If any function of the multi-function switch
is faulty, or if the switch is damaged, the entire
switch assembly must be replaced.
Fig. 1 Multi-Function Switch
REAR
The single two-function rear wiper and washer
switch is part of the inboard switch pod unit, which
is located on the instrument panel just inboard of the
steering column. The rear wiper and washer switch
controls the rear wiper and washer functions.
The sliding-type switch features a detent in the On
and Delay positions. The switch knob is depressed to
activate the rear washer system. Both the rear wiper
and rear washer motors will operate continuously for
as long as the switch is held in the momentary Wash
position.
The rear wiper and washer switch cannot be
repaired and, if faulty or damaged, the entire inboard
switch pod unit must be replaced.

BODY CONTROL MODULE

A Body Control Module (BCM) is used on this
model to control and integrate many of the electronic
functions and features included on the vehicle. The
BCM contains a central processing unit and inter-
faces with other modules in the vehicle on the
Chrysler Collision Detection (CCD) data bus network.
The CCD data bus network allows the sharing of
sensor information. This helps to reduce wire har-
ness complexity, reduce internal controller hardware,
and reduce component sensor current loads. At the
same time, this system provides increased reliability,
enhanced diagnostics, and allows the addition of
many new feature capabilities.
Some of the functions and features that the BCM
supports and controls are the speed sensitive inter-
mittent wipe, pulse wipe, and wipe-after-wash
CONTROL STALK H AZARD WARNING BUTTON MULTI-FUNCTION SWITCH
switch cannot
8K - 3
be