2002 JEEP GRAND CHEROKEE Signal

DESCRIPTION - OUTSIDE REAR VIEW MIRROR
An automatic dimming outside rear view mirror is
an available factory-installed option for the driver
side of the vehicle, if the vehicle is also equipped
with the automatic day/night inside rear view mirror.
The automatic dimming outside mirror is completely
controlled by the circuitry of the automatic day/night
inside rear view mirror. The automatic dimming out-
side mirror will automatically change the reflectance
of the driver side outside rear view mirror to protect
the driver from the unwanted headlight glare of
trailing vehicles while driving at night. The auto-
matic dimming outside mirror will only operate when
the ignition switch is in the On position.
The automatic dimming outside mirror sensitivity
cannot be repaired or adjusted. If any component of
this unit is faulty or damaged, the entire automatic
dimming outside mirror unit must be replaced. (Refer
to 8 - ELECTRICAL/POWER MIRRORS/SIDEVIEW
MIRROR - DIAGNOSIS AND TESTING). Refer to
the appropriate wiring information. The wiring infor-
mation includes wiring diagrams, proper wire and
connector repair procedures, details of wire harness
routing and retention, connector pin-out information
and location views for the various wire harness con-
nectors, splices and grounds.
OPERATION
OPERATION - REAR VIEW MIRROR
The automatic day/night mirror switch allows the
driver a manual control of whether the automatic
dimming feature is operational. This switch is a
momentary rocker-type switch located on the lower
rear-facing surface of the mirror housing. When Auto
is selected, a Light-Emitting Diode (LED) on the mir-
ror housing just to the right of the switch illuminates
to indicate that automatic day/night mirror is turned
on. When Off is selected, the LED is turned off. The
mirror also senses the backup lamp circuit, and will
automatically disable its self-dimming feature when-
ever the transmission gear selector is in the Reverse
position.
A thin layer of electrochromatic material between
two pieces of conductive glass make up the face of
the mirror. Two photocell sensors are used to monitor
light levels and adjust the reflectance of the mirror.
The ambient photocell sensor faces forward, to detect
the outside light levels. The headlamp sensor is
located on the mirror housing just to the left of the
switch and facing rearward, to detect the light level
received at the rear window side of the mirror. When
the difference between the two light levels becomes
too great (the light level received at the rear of themirror is much higher than that at the front of the
mirror), the mirror begins to darken.
On models with an optional driver side automatic
dimming outside mirror, the signal to control the
dimming of that mirror is generated by the auto-
matic day/night inside rear view mirror circuitry.
That signal is then delivered to the driver side out-
side rear view mirror on a hard wired circuit.
See the owner's manual in the vehicle glove box for
more information on the features, use and operation
of the automatic day/night mirror system.
OPERATION - OUTSIDE REAR VIEW MIRROR
The automatic dimming outside mirror is operated
by the same controls and circuitry as the automatic
day/night mirror. When the automatic day/night mir-
ror is turned on or off, the automatic dimming out-
side mirror is likewise turned on or off. Like in the
automatic day/night mirror, a thin layer of electro-
chromatic material between two pieces of conductive
glass make up the face of the automatic dimming
outside mirror. However, the signal to control the
dimming of the outside mirror is generated by the
automatic day/night inside rear view mirror circuitry.
See the owner's manual in the vehicle glove box for
more information on the features, use and operation
of the automatic dimming outside mirror.
DIAGNOSIS AND TESTING - AUTOMATIC DAY /
NIGHT MIRROR
For complete circuit diagrams, refer to the appro-
priate wiring information. The wiring information
includes wiring diagrams, proper wire and connector
repair procedures, details of wire harness routing
and retention, connector pin-out information and
location views for the various wire harness connec-
tors, splices and grounds.
(1) Check the fused ignition switch output (run/
start) fuse in the junction block. If OK, go to Step 2.
If not OK, repair the shorted circuit or component as
required and replace the faulty fuse.
(2) Turn the ignition switch to the On position.
Check for battery voltage at the fused ignition switch
output (run/start) fuse in the junction block. If OK,
go to Step 3. If not OK, repair the open fused ignition
switch output (run/start) circuit to the ignition switch
as required.
(3) Disconnect the overhead wire harness connec-
tor from the automatic day/night mirror connector
receptacle. Check for battery voltage at the fused
ignition switch output (run/start) circuit cavity of the
overhead wire harness connector for the automatic
day/night mirror. If OK, go to Step 4. If not OK,
repair the open fused ignition switch output (run/
start) circuit to the fuse in the junction block as
required.
WJPOWER MIRRORS 8N - 13
AUTOMATIC DAY/NIGHT MIRROR (Continued)

for the door module. There should be continuity. If
OK, use a DRB scan tool and the proper Diagnostic
Procedures manual to test the door module and the
PCI data bus. If not OK, replace the faulty power
mirror unit.
NO MIRROR DIMMING (Driver Side Only)
(1) Test the operation of the automatic day/night
mirror. (Refer to 8 - ELECTRICAL/POWER MIR-
RORS/AUTOMATIC DAY / NIGHT MIRROR -
OPERATION). If OK, go to Step 2. If not OK, repair
the automatic day/night mirror unit as required.
(2) Disconnect and isolate the battery negative
cable. Remove the driver side front door trim panel.
(3) Disconnect the door wire harness connector
from the power mirror wire harness connector. Con-
nect a voltmeter between the electrochromatic (+)and electrochromatic (±) circuit cavities of the door
wire harness connector for the power mirror. Turn on
the automatic day/night mirror system while observ-
ing the voltmeter. A voltmeter reading of 1.45   0.05
volts indicates a proper dimming signal is being
received at the door wire harness connector for the
power mirror. If OK, replace the faulty power mirror.
If not OK, repair the shorted or open electrochro-
matic (+) or electrochromatic (±) circuit(s) to the
automatic day/night mirror as required.
NO MIRROR MEMORY
For diagnosis of the memory system, the use of a
DRB scan tool and the proper Diagnostic Procedures
manual are recommended. (Refer to 8 - ELECTRI-
CAL/POWER SEATS - DESCRIPTION).
WJPOWER MIRRORS 8N - 17
SIDEVIEW MIRROR (Continued)

and no voltage in the neutral position. If OK,(Refer
to 8 - ELECTRICAL/POWER WINDOWS/WINDOW
MOTOR - DIAGNOSIS AND TESTING). If not OK,
replace the faulty door module.
(9) Check the rear door power window switch con-
tinuity. (Refer to 8 - ELECTRICAL/POWER WIN-
DOWS/POWER WINDOW SWITCH - DIAGNOSIS
AND TESTING). If OK, go to Step 10. If not OK,
replace the faulty rear door power window switch.
(10) Disconnect and isolate the battery negative
cable. Reconnect the door wire harness connector to
the rear door power window switch. Disconnect the
door wire harness connector from the inoperative
power window motor wire harness connector. Check
for continuity between the rear window driver up cir-
cuit cavity of the 15-way door wire harness connector
for the door module and a good ground. Repeat the
check for the rear window driver down circuit. In
each case there should be no continuity. If OK, go to
Step 11. If not OK, repair the shorted rear window
driver up or down circuit as required.
(11) Check for continuity between the rear window
driver up circuit cavities of the 15-way door wire har-
ness connector for the door module and the power
window motor wire harness connector. Repeat the
check for the rear window driver down circuit. In
each case there should be continuity. If OK, go to
Step 12. If not OK, repair the open rear window
driver up or down circuit as required.
NOTE: The door module feeds battery current to
both terminals of the rear door power window
motors when the power window lockout switch is in
the Unlock position, until the master window switch
on the driver side front door is actuated. The door
module feeds ground to both terminals of the rear
door power window motor when the power window
lockout switch is in the Lock position, until the
master window switch on the driver side front door
is actuated.
(12) Reconnect the 15-way door wire harness con-
nector for the door module to the door module con-
nector receptacle. Connect the battery negative cable.
Check for battery voltage at each cavity in the door
wire harness connector for the power window motor.
Each cavity should have battery voltage when the
power window switch is in the neutral position. Each
cavity should also have battery voltage in one other
switch position, either up or down, and zero volts
with the switch in the opposite position. If OK, (Refer
to 8 - ELECTRICAL/POWER WINDOWS/WINDOW
MOTOR - DIAGNOSIS AND TESTING). If not OK,
replace the faulty door module.POWER WINDOW SWITCH
DESCRIPTION
The power window motors are controlled by a two-
way momentary switch mounted on the trim panel of
each passenger door, and four two-way momentary
switches on the driver side front door trim panel. The
driver side front door trim panel also has a two-posi-
tion power window lockout switch. Each power win-
dow switch, except the lockout switch, is illuminated
by a Light-Emitting Diode (LED) that is integral to
the switch paddle.
The front door power window switches and the
power window lockout switch are integral to the
Driver Door Module (DDM) and Passenger Door
Module (PDM). The front door power window
switches and their lamps cannot be adjusted or
repaired and, if faulty or damaged, the entire DDM
or PDM unit must be replaced. The rear door power
window switches and their lamps cannot be adjusted
or repaired but, if faulty or damaged, only the
affected rear door power window switch must be
replaced. (Refer to 8 - ELECTRICAL/ELECTRONIC
CONTROL MODULES/DRIVER DOOR MODULE -
REMOVAL).
OPERATION
The front door power window switches provide an
up or down (or lock and unlock signal in the case of
the lockout switch) to the door module circuitry. The
Driver Door Module (DDM) circuitry controls the out-
put to the driver side front and rear door power win-
dow motors, and supplies electrical current as
required for the stand-alone operation of the driver
side rear door power window switch. The Passenger
Door Module (PDM) circuitry controls the output to
the passenger side front and rear door power window
motors, and supplies electrical current as required
for the stand-alone operation of the passenger side
rear door power window switch.
When a DDM-integrated master power window
switch for a passenger side window is actuated, or
when the power window lockout switch is actuated to
disable the passenger door power windows, the DDM
circuitry sends a message to the PDM over the Pro-
grammable Communications Interface (PCI) data bus
to control the output to that power window motor(s).
The power window switch for the driver side front
door power window has two detent positions in the
Down direction. The first detent provides normal
power window down operation. If this switch is
depressed to the second detent, the Auto Down cir-
cuitry of the DDM is activated. The Auto-Down cir-
cuitry will automatically move the driver side front
door window to its fully lowered position, even if the
power window switch is released. The Auto-Down
8N - 36 POWER WINDOWSWJ
POWER WINDOWS (Continued)

²Passenger Airbag- The passenger airbag is
located on the instrument panel, beneath the instru-
ment panel top pad and above the glove box on the
passenger side of the vehicle.
²Passenger Knee Blocker- The passenger knee
blocker is a structural reinforcement that is integral
to and concealed within the glove box door.
²Side Impact Sensor- Two side impact sensors
are used on vehicles with the optional side curtain
airbags, one left side and one right side. One sensor
is located behind the B-pillar trim near the base of
each B-pillar.
²Side Curtain Airbag- In vehicles equipped
with this option, a side curtain airbag is located on
each inside roof side rail above the headliner, and
extends from the A-pillar to just beyond the C-pillar.
The ACM and the EMIC each contain a central
processing unit and programming that allow them to
communicate with each other using the Programma-
ble Communication Interface (PCI) data bus network.
This method of communication is used by the ACM
for control of the airbag indicator on all models
equipped with dual front airbags. (Refer to 8 - ELEC-
TRICAL/ELECTRONIC CONTROL MODULES/
COMMUNICATION - DESCRIPTION).
Hard wired circuitry connects the supplemental
restraint system components to each other through
the electrical system of the vehicle. These hard wired
circuits are integral to several wire harnesses, which
are routed throughout the vehicle and retained by
many different methods. These circuits may be con-
nected to each other, to the vehicle electrical system,
and to the supplemental restraint system compo-
nents through the use of a combination of soldered
splices, splice block connectors, and many different
types of wire harness terminal connectors and insu-
lators. Refer to the appropriate wiring information.
The wiring information includes wiring diagrams,
proper wire and connector repair procedures, further
details on wire harness routing and retention, as well
as pin-out and location views for the various wire
harness connectors, splices and grounds.
OPERATION
ACTIVE RESTRAINTS
The primary passenger restraints in this or any
other vehicle are the standard equipment factory-in-
stalled seat belts. Seat belts are referred to as an
active restraint because the vehicle occupants are
required to physically fasten and properly adjust
these restraints in order to benefit from them. See
the owner's manual in the vehicle glove box for more
information on the features, use and operation of all
of the factory-installed active restraints.PASSIVE RESTRAINTS
The passive restraints system is referred to as a
supplemental restraint system because they were
designed and are intended to enhance the protection
for the vehicle occupants of the vehicleonlywhen
used in conjunction with the seat belts. They are
referred to as passive systems because the vehicle
occupants are not required to do anything to make
them operate; however, the vehicle occupants must
be wearing their seat belts in order to obtain the
maximum safety benefit from the factory-installed
supplemental restraint systems.
The supplemental restraint system electrical cir-
cuits are continuously monitored and controlled by a
microprocessor and software contained within the
Airbag Control Module (ACM). An airbag indicator in
the ElectroMechanical Instrument Cluster (EMIC)
illuminates for about seven seconds as a bulb test
each time the ignition switch is turned to the On or
Start positions. Following the bulb test, the airbag
indicator is turned on or off by the ACM to indicate
the status of the supplemental restraint system. If
the airbag indicator comes on at any time other than
during the bulb test, it indicates that there is a prob-
lem in the supplemental restraint system electrical
circuits. Such a problem may cause airbags not to
deploy when required, or to deploy when not
required.
Deployment of the supplemental restraints
depends upon the angle and severity of an impact.
Deployment is not based upon vehicle speed; rather,
deployment is based upon the rate of deceleration as
measured by the forces of gravity (G force) upon the
impact sensors. When an impact is severe enough,
the microprocessor in the ACM signals the inflator
unit of the airbag module to deploy the airbag. Dur-
ing a frontal vehicle impact, the knee blockers work
in concert with properly fastened and adjusted seat
belts to restrain both the driver and the front seat
passenger in the proper position for an airbag deploy-
ment. The knee blockers also absorb and distribute
the crash energy from the driver and the front seat
passenger to the structure of the instrument panel.
Typically, the vehicle occupants recall more about
the events preceding and following a collision than
they have of an airbag deployment itself. This is
because the airbag deployment and deflation occur so
rapidly. In a typical 48 kilometer-per-hour (30 mile-
per-hour) barrier impact, from the moment of impact
until the airbags are fully inflated takes about 40
milliseconds. Within one to two seconds from the
moment of impact, the airbags are almost entirely
deflated. The times cited for these events are approx-
imations, which apply only to a barrier impact at the
given speed. Actual times will vary somewhat,
8O - 4 RESTRAINTSWJ
RESTRAINTS (Continued)

WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, DISABLE THE SUPPLEMENTAL RESTRAINT
SYSTEM BEFORE ATTEMPTING ANY STEERING
WHEEL, STEERING COLUMN, DRIVER AIRBAG,
PASSENGER AIRBAG, FRONT IMPACT SENSOR,
SIDE IMPACT SENSOR, SIDE CURTAIN AIRBAG, OR
INSTRUMENT PANEL COMPONENT DIAGNOSIS OR
SERVICE. DISCONNECT AND ISOLATE THE BAT-
TERY NEGATIVE (GROUND) CABLE, THEN WAIT
TWO MINUTES FOR THE SYSTEM CAPACITOR TO
DISCHARGE BEFORE PERFORMING FURTHER
DIAGNOSIS OR SERVICE. THIS IS THE ONLY SURE
WAY TO DISABLE THE SUPPLEMENTAL
RESTRAINT SYSTEM. FAILURE TO TAKE THE
PROPER PRECAUTIONS COULD RESULT IN ACCI-
DENTAL AIRBAG DEPLOYMENT AND POSSIBLE
PERSONAL INJURY.
STANDARD PROCEDURE
STANDARD PROCEDURE - HANDLING
NON-DEPLOYED SUPPLEMENTAL RESTRAINTS
At no time should any source of electricity be per-
mitted near the inflator on the back of a non-de-
ployed airbag. When carrying a non-deployed airbag,
the trim cover or airbag cushion side of the unit
should be pointed away from the body to minimize
injury in the event of an accidental deployment. If
the airbag unit is placed on a bench or any other sur-
face, the trim cover or airbag cushion side of the unit
should be face up to minimize movement in the event
of an accidental deployment. In addition, the supple-
mental restraint system should be disarmed when-
ever any steering wheel, steering column, driver
airbag, passenger airbag, front impact sensor, side
impact sensor, side curtain airbag, or instrument
panel components require diagnosis or service. Fail-
ure to observe this warning could result in accidental
airbag deployment and possible personal injury.
All damaged, faulty or non-deployed airbags which
are replaced on vehicles are to be handled and dis-
posed of properly. If an airbag unit is faulty or dam-
aged and non-deployed, refer to the Hazardous
Substance Control System for proper disposal. Dis-
pose of all non-deployed and deployed airbags in a
manner consistent with state, provincial, local and
federal regulations.
SUPPLEMENTAL RESTRAINT STORAGE
Airbags must be stored in their original, special
container until they are used for service. Also, they
must be stored in a clean, dry environment; away
from sources of extreme heat, sparks, and high elec-
trical energy. Always place or store any airbag on a
surface with its trim cover or airbag cushion side fac-ing up, to minimize movement in case of an acciden-
tal deployment.
STANDARD PROCEDURE - SERVICE AFTER A
SUPPLEMENTAL RESTRAINT DEPLOYMENT
Any vehicle which is to be returned to use follow-
ing a supplemental restraint deployment, must have
the deployed restraints replaced. In addition, if the
driver airbag has been deployed, the clockspring
must be replaced. If the passenger airbag is
deployed, the instrument panel top pad must be
replaced. If a side curtain airbag has been deployed,
the complete airbag unit, the headliner, as well as
the upper A, B, C and D-pillar trim must be replaced.
These components are not intended for reuse and
will be damaged or weakened as a result of a supple-
mental restraint deployment, which may or may not
be obvious during a visual inspection.
The passenger airbag mounting points on the
instrument panel structural duct must be closely
inspected for damage, and the instrument panel
assembly replaced if structural duct damage is evi-
dent. On vehicles with an optional sunroof, the sun-
roof drain tubes and hoses must be closely inspected
following a side curtain airbag deployment. It is also
critical that the mounting surfaces and/or mounting
brackets for the front and side impact sensors be
closely inspected and restored to their original condi-
tions following any vehicle impact damage. Because
the ACM and each impact sensor are used by the
supplemental restraint system to monitor or confirm
the direction and severity of a vehicle impact,
improper orientation or insecure fastening of these
components may cause airbags not to deploy when
required, or to deploy when not required.
All other vehicle components should be closely
inspected following any supplemental restraint
deployment, but are to be replaced only as required
by the extent of the visible damage incurred.
AIRBAG SQUIB STATUS
Multistage airbags with multiple initiators (squibs)
must be checked to determine that all squibs were
used during the deployment event. The driver and
passenger airbags in this model are deployed by elec-
trical signals generated by the Airbag Control Mod-
ule (ACM) through the driver or passenger squib 1
and squib 2 circuits to the two initiators in the air-
bag inflators. Typically, both initiators are used and
all potentially hazardous chemicals are burned dur-
ing an airbag deployment event. However, it is possi-
ble for only one initiator to be used due to an airbag
system fault; therefore, it is always necessary to con-
firm that both initiators have been used in order to
avoid the improper handling or disposal of poten-
tially live pyrotechnic or hazardous materials. The
8O - 6 RESTRAINTSWJ
RESTRAINTS (Continued)

The ACM microprocessor continuously monitors all
of the supplemental restraint system electrical cir-
cuits to determine the system readiness. If the ACM
detects a monitored system fault, it sets an active
and stored Diagnostic Trouble Code (DTC) and sends
electronic messages to the EMIC over the PCI data
bus to turn on the airbag indicator. An active fault
only remains for the duration of the fault or in some
cases the duration of the current ignition switch
cycle, while a stored fault causes a DTC to be stored
in memory by the ACM. For some DTCs, if a fault
does not recur for a number of ignition cycles, the
ACM will automatically erase the stored DTC. For
other internal faults, the stored DTC is latched for-
ever.
The ACM receives battery current through two cir-
cuits, on a fused ignition switch output (run) circuit
through a fuse in the Junction Block (JB), and on a
fused ignition switch output (start-run) circuit
through a second fuse in the JB. The ACM is
grounded through a ground circuit and take out of
the instrument panel floor wire harness. This take
out has a single eyelet terminal connector secured by
a nut to a ground stud located behind the ACM
mount on the floor panel transmission tunnel. These
connections allow the ACM to be operational when-
ever the ignition switch is in the Start or On posi-
tions. The ACM also contains an energy-storage
capacitor. When the ignition switch is in the Start or
On positions, this capacitor is continually being
charged with enough electrical energy to deploy the
airbags for up to one second following a battery dis-
connect or failure. The purpose of the capacitor is to
provide backup supplemental restraint system pro-
tection in case there is a loss of battery current sup-
ply to the ACM during an impact.
Two sensors are contained within the ACM, an
electronic impact sensor and a safing sensor. The
ACM also monitors inputs from two remote front
impact sensors located on brackets on the inboard
sides of the right and left vertical members of the
radiator support near the front of the vehicle. The
electronic impact sensors are accelerometers that
sense the rate of vehicle deceleration, which provide
verification of the direction and severity of an
impact. On models equipped with optional side cur-
tain airbags, the ACM also monitors inputs from two
remote side impact sensors located near the base of
both the left and right inner B-pillars to control the
deployment of the side curtain airbag units.
The safing sensor is an electronic accelerometer
sensor within the ACM that provides an additional
logic input to the ACM microprocessor. The safingsensor is used to verify the need for an airbag
deployment by detecting impact energy of a lesser
magnitude than that of the primary electronic impact
sensors, and must exceed a safing threshold in order
for the airbags to deploy. The ACM also monitors a
Hall effect-type seat belt switch located in the buckle
of each front seat belt to determine whether the seat-
belts are buckled, and provides an input to the EMIC
over the PCI data bus to control the seatbelt indica-
tor operation based upon the status of the driver side
front seat belt switch. Vehicles with the optional side
curtain airbags feature a second safing sensor within
the ACM to provide confirmation to the ACM of side
impact forces. This second safing sensor is a bi-direc-
tional unit that detects impact forces from either side
of the vehicle.
Pre-programmed decision algorithms in the ACM
microprocessor determine when the deceleration rate
as signaled by the impact sensors and the safing sen-
sors indicate an impact that is severe enough to
require supplemental restraint system protection.
The ACM also determines the level of front airbag
deployment force required for each front seating posi-
tion based upon the status of the two seat belt switch
inputs and the severity of the monitored impact.
When the programmed conditions are met, the ACM
sends the proper electrical signals to deploy the mul-
tistage dual front airbags at the programmed force
levels, and to deploy either side curtain airbag.
The hard wired inputs and outputs for the ACM
may be diagnosed and tested using conventional
diagnostic tools and procedures. However, conven-
tional diagnostic methods will not prove conclusive in
the diagnosis of the ACM, the PCI data bus network,
or the electronic message inputs to and outputs from
the ACM. The most reliable, efficient, and accurate
means to diagnose the ACM, the PCI data bus net-
work, and the electronic message inputs to and out-
puts from the ACM requires the use of a DRBIIIt
scan tool. Refer to the appropriate diagnostic infor-
mation.
REMOVAL
Two different Airbag Control Modules (ACM) are
available for this vehicle. For vehicles equipped with
the optional side curtain airbags, both ACM connec-
tor receptacles are black in color and the ACM con-
tains a second bi-directional safing sensor for the
side airbags. For vehicles not equipped with the
optional side curtain airbags, the ACM connector
receptacles are gray.
8O - 10 RESTRAINTSWJ
AIRBAG CONTROL MODULE (Continued)

INSTALLATION
The following service procedure applies to vehicles
manufactured for sale in North America, which have
removable child seat tether anchor brackets that are
located on the inner liftgate opening header. Vehicles
manufactured for sale in Rest-Of-World (ROW) mar-
kets have child tether anchors that are integral to,
and are only serviced with the rear seat back panels.
(1) Position the child tether anchor bracket onto
the inner liftgate opening header (Fig. 12).
(2) Install and tighten the screw that secures the
child tether anchor bracket to the inner liftgate open-
ing header. Tighten the screw to 11.8 N´m (105 in.
lbs.).
(3) Reinstall the cover into the child tether anchor
bezel in the headliner near the liftgate opening
header.
CLOCKSPRING
DESCRIPTION
The clockspring assembly is secured with two
screws to the multi-function switch mounting hous-
ing near the top of the steering column behind the
steering wheel (Fig. 13). The clockspring consists of a
flat, round molded plastic case with a stubby tail
that hangs below the steering column and contains
two connector receptacles that face toward the
instrument panel (Fig. 14). Within the plastic hous-ing is a spool-like molded plastic rotor with a large
exposed hub. The upper surface of the rotor hub has
a large center hole, two large flats, an index hole,
two short pigtail wires with connectors, and two con-
nector receptacles that face toward the steering
wheel.
The lower surface of the rotor hub has three pins,
two round and one oblong. These pins index the
clockspring to the turn signal cancel cam unit in the
multi-function switch mounting housing. Within the
plastic case and wound around the rotor spool is a
long ribbon-like tape that consists of several thin cop-
per wire leads sandwiched between two thin plastic
membranes. The outer end of the tape terminates at
the connector receptacles that face the instrument
panel, while the inner end of the tape terminates at
the pigtail wires and connector receptacles on the
hub of the clockspring rotor that face the steering
wheel.
Service replacement clocksprings are shipped pre-
centered and with a molded plastic locking pin
installed. The locking pin secures the centered clock-
spring rotor to the clockspring case during shipment
and handling, but must be removed from the clock-
spring after it and the multi-function switch mount-
ing housing are installed on the steering column.
(Refer to 8 - ELECTRICAL/RESTRAINTS/CLOCK-
SPRING - STANDARD PROCEDURE - CLOCK-
SPRING CENTERING).
The clockspring cannot be repaired. If the clock-
spring is faulty, damaged, or if the driver airbag has
been deployed, the clockspring must be replaced.
Fig. 13 Clockspring (Upper View)
1 - MOUNTING EAR (2)
2 - LOCKING PIN
3 - UPPER CONNECTOR RECEPTACLE (2)
4 - LABEL
5 - OBLONG PIN
6 - ALIGNMENT ARROWS
7 - CASE
8 - PIGTAIL WIRE (2)
Fig. 14 Clockspring (Lower View)
1 - LOCKING PIN
2 - CASE
3 - OBLONG PIN
4 - ROUND PIN (2)
5 - LOWER CONNECTOR RECEPTACLE (2)
6 - ROTOR
8O - 14 RESTRAINTSWJ
CHILD TETHER ANCHOR (Continued)

OPERATION
The clockspring is a mechanical electrical circuit
component that is used to provide continuous electri-
cal continuity between the fixed instrument panel
wire harness and the electrical components mounted
on or in the rotating steering wheel. On this model
the rotating electrical components include the driver
airbag, the horn switch, the speed control switches,
and the remote radio switches, if the vehicle is so
equipped. The clockspring case is positioned and
secured to the multi-function switch mounting hous-
ing on the upper steering column housing by two
screws. The two connector receptacles on the tail of
the fixed clockspring case connect the clockspring to
the vehicle electrical system through two take outs
with connectors from the instrument panel wire har-
ness. The clockspring rotor is movable and is keyed
to the hub of the steering wheel by two large flats
that are molded into the rotor hub. The three pins
(two round and one oblong) on the lower surface of
the clockspring rotor hub engage and index the clock-
spring rotor to the turn signal cancel cam. The turn
signal cancel cam is integral to the multi-function
switch mounting housing and is keyed to the upper
steering column shaft. Two short, yellow-sleeved pig-
tail wires on the upper surface of the clockspring
rotor connect the clockspring to the driver airbag,
while a steering wheel wire harness connects the two
connector receptacles on the upper surface of the
clockspring rotor to the horn switch, the two speed
control switches, and the remote radio switches on
vehicles that are so equipped.
Like the clockspring in a timepiece, the clockspring
tape has travel limits and can be damaged by being
wound too tightly during full stop-to-stop steering
wheel rotation. To prevent this from occurring, the
clockspring must be centered when it is installed on
the steering column. Centering the clockspring
indexes the clockspring tape to the movable steering
components so that the tape can operate within its
designed travel limits. However, if the clockspring is
removed from the steering column or if the steering
shaft is disconnected from the steering gear, the
clockspring spool can change position relative to the
movable steering components and must be re-cen-
tered following completion of the service or the tape
may be damaged. Service replacement clocksprings
are shipped pre-centered and with a locking pin
installed. This locking pin should not be removed
until the clockspring has been installed on the steer-
ing column. If the locking pin is removed before the
clockspring is installed on a steering column, the
clockspring centering procedure must be performed.
(Refer to 8 - ELECTRICAL/RESTRAINTS/CLOCK-
SPRING - STANDARD PROCEDURE - CLOCK-
SPRING CENTERING).
STANDARD PROCEDURE - CLOCKSPRING
CENTERING
The clockspring is designed to wind and unwind
when the steering wheel is rotated, but is only
designed to rotate the same number of turns (about
five complete rotations) as the steering wheel can be
turned from stop to stop. Centering the clockspring
indexes the clockspring tape to other steering compo-
nents so that it can operate within its designed
travel limits. The rotor of a centered clockspring can
be rotated two and one-half turns in either direction
from the centered position, without damaging the
clockspring tape.
However, if the clockspring is removed for service
or if the steering column is disconnected from the
steering gear, the clockspring tape can change posi-
tion relative to the other steering components. The
clockspring must then be re-centered following com-
pletion of such service or the clockspring tape may be
damaged. Service replacement clocksprings are
shipped pre-centered and with a molded plastic lock-
ing pin installed. This locking pin should not be
removed until the clockspring has been installed on
the steering column. If the locking pin is removed
before the clockspring is installed on a steering col-
umn, the clockspring centering procedure must be
performed.
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, DISABLE THE SUPPLEMENTAL RESTRAINT
SYSTEM BEFORE ATTEMPTING ANY STEERING
WHEEL, STEERING COLUMN, DRIVER AIRBAG,
PASSENGER AIRBAG, FRONT IMPACT SENSOR,
SIDE IMPACT SENSOR, SIDE CURTAIN AIRBAG, OR
INSTRUMENT PANEL COMPONENT DIAGNOSIS OR
SERVICE. DISCONNECT AND ISOLATE THE BAT-
TERY NEGATIVE (GROUND) CABLE, THEN WAIT
TWO MINUTES FOR THE SYSTEM CAPACITOR TO
DISCHARGE BEFORE PERFORMING FURTHER
DIAGNOSIS OR SERVICE. THIS IS THE ONLY SURE
WAY TO DISABLE THE SUPPLEMENTAL
RESTRAINT SYSTEM. FAILURE TO TAKE THE
PROPER PRECAUTIONS COULD RESULT IN ACCI-
DENTAL AIRBAG DEPLOYMENT AND POSSIBLE
PERSONAL INJURY.
NOTE: Before starting this procedure, be certain to
turn the steering wheel until the front wheels are in
the straight-ahead position.
(1) Place the front wheels in the straight-ahead
position.
(2) Remove the clockspring from the steering col-
umn. (Refer to 8 - ELECTRICAL/RESTRAINTS/
CLOCKSPRING - REMOVAL).
WJRESTRAINTS 8O - 15
CLOCKSPRING (Continued)