(Fig. 8). The actuator assembly is mounted between
the height sensing proportioning valve and the actua-
tor bracket on the left rear leaf spring (Fig. 8). As the
rear height of the vehicle changes depending on the
load the vehicle is carrying the height change is
transferred to the height sensing proportioning valve.
This change in vehicle height is transferred through
the movement of the left rear leaf spring. As the posi-
tion of the left rear leaf spring changes this move-
ment is transferred through the actuator bracket
(Fig. 8) to the actuator assembly (Fig. 8) and then to
the proportioning valve.
Thus, the height sensing proportioning valve
allows the brake system to maintain the optimal
front to rear brake balance regardless of the vehicle
load condition. Under a light load condition, hydrau-
lic pressure to the rear brakes is minimized. As the
load condition of the vehicle increases, so does the
hydraulic pressure to the rear brakes.
The proportioning valve section of the valve oper-
ates by transmitting full input hydraulic pressure to
the rear brakes up to a certain point, called the split
point. Beyond the split point the proportioning valve
reduces the amount of hydraulic pressure to the rear
brakes according to a certain ratio. Thus, on light
brake applications, approximately equal hydraulic
pressure will be transmitted to the front and rear
brakes. At heavier brake applications, the hydraulic
pressure transmitted to the rear brakes will be lower
then the front brakes. This will prevent premature
rear wheel lock-up and skid.
The height sensing section of the valve thus
changes the split point of the proportioning valve,
based on the rear suspension height of the vehicle.
When the height of the rear suspension is low, the
proportioning valve interprets this as extra load and
the split point of the proportioning valve is raised to
allow more rear braking. When the height of the rear
suspension is high, the proportioning valve interprets
this as a lightly loaded vehicle and the split point of
the proportioning valve is lowered and rear braking
is reduced.
CHASSIS TUBES AND HOSES
The purpose of the chassis brake tubes and flex
hoses is to transfer the pressurized brake fluid devel-
oped by the master cylinder to the wheel brakes of
the vehicle. The chassis tubes are steel with a corro-
sion resistant coating applied to the external surfaces
and the flex hoses are made of reinforced rubber. The
rubber flex hoses allow for the movement of the vehi-
cles suspension.
MASTER CYLINDER
The master cylinder (Fig. 9) consists of the follow-
ing components. The body of the master cylinder isan anodized aluminum casting. It has a machined
bore to accept the master cylinder piston and
threaded ports with seats for the hydraulic brake
line connections. The brake fluid reservoir of the
master cylinder assembly is made of a see through
polypropylene type plastic. A low fluid switch is also
part of the reservoir assembly.
This vehicle uses 3 different master cylinders.
Master cylinder usage depends on what type of brake
system the vehicle is equipped with. If a vehicle is
not equipped with antilock brakes, or is equipped
with antilock brakes without traction control, a con-
ventional compensating port master cylinder is used.
If a vehicle is equipped with antilock brakes with
traction control, a dual center port master cylinder is
used.
The third master cylinder used on this vehicle is
unique to vehicles equipped with four wheel disc
brakes. The master cylinder used for this brake
application has a different bore diameter and stroke
then the master cylinder used for the other available
brake applications.
The master cylinders used on front wheel drive
applications (non four wheel disc brake vehicles)
have a master cylinder piston bore diameter of 23.8
mm. The master cylinder used on the all wheel drive
applications (four wheel disc brake vehicles) have a
master cylinder piston bore diameter of 25.4 mm.
When replacing a master cylinder, be sure to
use the correct master cylinder for the type of
brake system the vehicle is equipped with.
The master cylinder is not a repairable component
and must be replaced if diagnosed to be functioning
improperly
CAUTION: Do not hone the bore of the cylinder as
this will remove the anodized surface from the bore.
The master cylinder primary outlet port supplies
hydraulic pressure to the right front and left rear
Fig. 9 Master Cylinder Assembly
NSBRAKES 5 - 7
DESCRIPTION AND OPERATION (Continued)
QUICK CONNECT COUPLING Ð RHD
CAUTION: Do not actuate the master cylinder or
step on the clutch pedal before the quick connect
coupling is joined, or an over pressure condition
could result in damage to the master cylinder, the
quick connect coupling, or the dash panel.
REMOVAL
1. Disconnect the quick connect coupling by lightly
pushing down on the black release collar on the male
side of the quick connect coupling while separating it
from the female side of the quick connect coupling
(Fig. 14).
INSTALLATION
1. Connect the male side of the quick connect cou-
pling (part of the master cylinder assembly) by hold-
ing the clutch tube at the rear and inserting it into
the female side of the quick connect coupling (part of
the slave cylinder assembly) until an audible click is
heard (Fig. 14).Do not push on the black release
collar on the male side of the quick connect
coupling while inserting it into the female side
of the quick connect coupling.
2. Confirm the connection by pulling firmly on the
clutch tube.
MASTER CYLINDER SYSTEM Ð RHD
REMOVAL
(1) Disconnect the quick connect coupling. Refer to
the ªQuick Connect Couplingº removal and installa-
tion procedure in this section.
(2) Remove the master cylinder pushrod from the
clutch pedal pin by prying between the self-retaining
snap-on bushing, located in the master cylinder
pushrod, and the clutch pedal pin (Fig. 15).
(3) Disconnect the hydraulic line from the weld
stud clips (Fig. 14).
(4) Remove the rubber grommet at the master cyl-
inder pass through in the dash panel (Fig. 16).
(5) Remove the master cylinder assembly from the
engine compartment by rotating it clockwise from the
12 o'clock lock position to the 2 o'clock unlock posi-
tion and pulling the master cylinder out tilted 20
degrees down.NOTE: A ªTwist and Lockº type
mechanism is used to secure the master cylin-
der to the clutch pedal bracket which is
attached to the dash panel.
INSTALLATION
(1) Position the master cylinder assembly to the
clutch pedal bracket by tilting it 20 degrees upward
and at the 2 o'clock unlocked position.
(2) Rotate the master cylinder counterclockwise to
the 12 o'clock locked position.
(3) Install the rubber grommet into the dash panel
at the master cylinder pass through (Fig. 16).
(4) Connect the hydraulic line to the weld stud
clips in the engine compartment (Fig. 14).
(5) Connect the quick connect coupling. Refer to
the ªQuick Connect Couplingº removal and installa-
tion procedure in this section.
(6) Install the self-retaining snap-on bushing into
the master cylinder pushrod, if necessary.
(7) Install the master cylinder pushrod with self-
retaining snap-on bushing onto the clutch pedal pin
by pressing it onto the clutch pedal pin until seats in
the groove of the clutch pedal pin.
SLAVE CYLINDER ASSEMBLY Ð RHD
REMOVAL
1. Disconnect the quick connect coupling. Refer to
the ªQuick Connect Couplingº removal and installa-
tion procedure in this section.
2. Remove the nut and washer assemblies (2)
retaining the slave cylinder and mounting bracket
assembly to the transaxle (Fig. 14).
3. Remove the slave cylinder assembly from the
transaxle.
Fig. 16 Clutch Master Cylinder Ð RHD
6 - 12 CLUTCHNS/GS
REMOVAL AND INSTALLATION (Continued)
SERVICE PROCEDURES
HORN CHIRP DISABLE OR ENABLE
The horn chirp can be DISABLED or ENABLED
using the following procedure.
To DISABLE (cancelling) the horn chirp feature,
press and hold the transmitter LOCK button for a
minimum four seconds. While pressing LOCK button
in, press the UNLOCK button. The horn chirp fea-
ture will not function until the above procedure is
repeated. To ENABLE (reinstate) the horn chirp fea-
ture, use any one of the four key fob transmitters
and reverse the above procedures. It will ENABLE
the horn chirp feature for all transmitters.
REMOVAL AND INSTALLATION
RKE MODULE
REMOVAL
(1) Remove instrument panel top cover. Refer to
Group 8E, Instrument Panel and Gauges for proper
procedures.
(2) Remove screws holding RKE module to instru-
ment panel.
(3) Disconnect wire connector from RKE module
(Fig. 2).
(4) Remove the RKE module.
INSTALLATION
For installation, reverse the above procedures.
ADJUSTMENTS
PROGRAMMING RKE MODULE
(1) Using a functional key fob transmitter, unlock
the vehicle and disarm the Vehicle Theft Security
System.
(2) Insert ignition key into the ignition switch.
(3) Turn the ignition switch to RUN position with-
out starting engine.
(4) Using a functional key fob transmitter, press
and hold the UNLOCK button for a minimum four
seconds (maximum ten seconds).
(5) While holding UNLOCK button, and before ten
seconds passes, press and release the PANIC button.
A single chime will sound to verify that the RKE
module is set to receive the new Vehicle Access
Code(s).
(6) Within 30 seconds of the chime, press any but-
ton on each new key fob transmitter. After 30 sec-
onds or when ignition switch is turned OFF, the RKE
module will end the programming mode. A single
chime will sound to verify that the RKE module will
no longer receive additional Vehicle Access Code(s).
(7) When Vehicle Access Code(s) programming is
complete, turn Ignition Switch to the OFF position
and verify RKE system operation using each key fob.
NOTE: Only the primary (first two) key fob transmit-
ters will operate the memory seat and mirror sys-
tems. If a primary key fob is being replaced, the
memory seat and mirror module will require pro-
gramming. Refer to Group 8R, Power Seats for
proper (data link) programming procedure.
SPECIFICATIONS
RKE TRANSMITTER BATTERY
The batteries can be removed without special tools
and are readily available at local retail stores. The
recommended battery is Duracell DL 2016 or equiva-
lent. Battery life is about one to two years.
CAUTION: Do not touch the battery terminals or
handle the batteries any more than necessary.
Hands must be clean and dry.
RKE TRANSMITTER RANGE
Normal operation range is up to about a distance
of 7 meters (23 ft.) of the vehicle. Range may be bet-
ter or worse depending on the environment around
the vehicle. Closeness to a radio frequency transmit-
ter such as a radio station tower may degrade oper-
ational range, while range in an open field will be
enhanced.
Fig. 2 RKE Module
8P - 6 POWER DOOR LOCKSNS
POWER SEATS
CONTENTS
page page
MEMORY SEAT AND MIRROR SYSTEM....... 3POWER SEATS........................... 1
POWER SEATS
INDEX
page page
GENERAL INFORMATION
INTRODUCTION......................... 1
DIAGNOSIS AND TESTING
DIAGNOSTIC PROCEDURES................ 1POWER SEAT SWITCH.................... 1
SEATMOTORS .......................... 1
GENERAL INFORMATION
INTRODUCTION
Power seats can be adjusted in eight directions; up,
down, forward, back, tilt forward, or tilt rearward.
Four reversible motors and a transmission located on
the seat tracks provide the various seat movements.
The electrical circuit is protected by a 40 amp fuse in
the Power Distribution Center (PDC) and a 30 amp
circuit breaker located in the wire harness under the
driver's seat.
DIAGNOSIS AND TESTING
DIAGNOSTIC PROCEDURES
Before testing the seat functions, verify that the
battery is fully charged and the terminals cleaned
and tightened to ensure proper connections. If the
battery is not fully charged, refer to Group 8A Bat-
tery for proper testing procedures.
The following test will determine if the circuit is
complete through the body harness to the switch:
Using a voltmeter, verify the condition of the power
seat circuit breaker located under the driver's seat.
The circuit breaker also protects the passenger side
power seat track circuit. Check both sides of the cir-
cuit breaker connector for voltage, on the wire side.
²If not OK replace circuit breaker.
²If battery voltage is detected on both sides of the
circuit breaker. Refer to Seat Motor in the Diagnostic
and Testing in this section.²If seat motors test OK, refer to the Seat Switch
in the Diagnostic and Testing in this section.
²Refer to Group 8W Wiring Diagrams for wire
circuit information.
SEAT MOTORS
(1) Remove power seat switch from seat. Refer to
Group 23 Body for procedures.
(2) Disconnect wire connector.
(3) Using a voltmeter check for battery voltage at
Pin 5. Using an ohmmeter, check Pin 1 for ground.
(4) To test the seat motors, refer to (Fig. 1) and
verify proper seat responses. Using two jumper
wires, connect one to a battery supply and the other
to a ground. Connect the other ends to the seat wire
harness connector as described in (Fig. 1). If any
motor fails to operate, check wire connectors to the
motor. If not OK, repair as necessary. If OK, replace
seat motor/track assembly.
POWER SEAT SWITCH
(1) Remove power seat switch from seat. Refer to
Group 23 Body for procedures.
(2) Using an ohmmeter, perform the switch conti-
nuity tests in (Fig. 2). If there is no continuity at any
of the switch positions, replace switch.
NSPOWER SEATS 8R - 1
two positions of seat and recliner, and the side view
mirrors as chosen by the driver.
The inputs from these switches to the memory
seat/mirror module is a ground level signal.
(1) Adjust the seat, recliner and side view mirrors
to the desired position.
(2)
Press momentarily and release memory switch S.
(3) Press momentarily and release memory switch
1 or 2. Do NOT press any switches for 10 seconds.
(4) To program the second driver's position, follow
the above sequence.
(5) To recall either of the programmed positions
momentarily press and release either memory selec-
tor switch 1 or 2.
DEFINITION OF: MOMENTARILY AND
RELEASE
The memory seat/mirror module has switch input
timing requirements of a minimum press momen-
tarily time of 250 milliseconds followed by a maxi-
mum hold time of 5 seconds, followed by a maximum
release time between steps of 5 seconds that must be
met for proper operation of the system.
SEAT AND RECLINER SWITCHES
The seat and recliner switch assembly is mounted
outboard on the seat side-shield. Press and hold the
desired seat or recliner switch to effect movement.
The Memory Seat/Mirror Module (MSM Module) will
drive a maximum of 2 motors at a time in a given
direction. If conflicting directions are requested, the
priority for response will be as follows:
²Seat Track Rearward
²Seat Front Down
²Seat Rear Down
²Recliner Rearward
²Seat Track Forward
²Seat Front Up
²Seat Rear Up
²Recliner Forward
The inputs from these switches to the MSM Mod-
ule is a current limited battery source fed by the
MSM Module. This protects the MSM Module printed
circuit board traces from acting as fuses. All of these
switch contact inputs to the module are normally
closed to ground, except when actuated.
POSITION SENSING SEAT AND RECLINER
POTENTIOMETERS
A potentiometer is mounted to each seat track and
recliner motor end-bell to provide a sense voltage to
the Memory Seat/Mirror Module that will indicate to
the module where the seat track or recliner is posi-
tioned.
This sense voltage is derived from a 5 volt source
provided by the module to the potentiometer. Thesense voltage is input into the module and stored by
the Memory Seat/Mirror Module.
DIAGNOSIS AND TESTING
MEMORY SELECTOR SWITCHES
To test the memory selector switch:
(1) Remove the memory selector switch. Refer to
removal procedure.
(2) Using an ohmmeter check continuity reading
between switch pins. Refer to (Fig. 1) for proper Pin
numbers.
SIDE VIEW MIRROR SWITCH STUCK
The mirror switches in the instrument panel have
normally open contacts when in their inactive state.
The left/right rocker switch has a center-off detent. If
this switch is actuated to either side, it then becomes
connected to the P73/P70, circuits which are the mir-
ror motor common connections. No faults will result
from this action by itself. If one of the other switch
contacts from the round portion of the switch
becomes accidentally closed,It can cause problems
such as both mirrors operating at the same
time in the vertical or horizontal modes.
²Turn ignition switch ON: If two mirror switch
contacts, from the round portion, are stuck in the
closed position, and the left/right portion is actuated
to either side, a mirror motor will become actuated.
This will drive the motor to its stop, where it will
keep ratcheting until a switch contact is released or
the ignition is turned to OFF. Replace the mirror
switch assembly to correct this condition.
²With the ignition switch in the ON or the OFF
position: If only one mirror switch contact is stuck in
the closed position, the mirror motor will not become
actuated. During an ignition switch recall of a driv-
Fig. 1 Memory Selector Switch Continuity
8R - 4 POWER SEATSNS
DESCRIPTION AND OPERATION (Continued)
nector (cavity 5)This is a low current battery
feed from the control module that will not illu-
minate a test lamp.
During shipping of the vehicle, an M1 circuit 10
amp fuse (labeled IOD) is temporarily removed from
the PDC in the engine compartment to eliminate
unnecessary battery depletion. However, this fused
circuit being open (that feeds through the electrical
distribution wiring to cavity 16 of the 25-way connec-
tor) will not stop manual seat actuations from taking
place (only recall mode requests) during shipping.
(1) If the memory seat/mirror module does not
respond with a relay click to any seat switch input
(as well as the desired motion) when actuated, pro-
ceed with the following analysis:²Verify power ON F35 and ground Z1 into the
system as indicated above.
²Verify all connectors are mated with the memory
seat/mirror module.
²Place the vehicle gear shift lever in any position
except PARK (causes the Memory Seat/Mirror Mod-
ule to wake-up and provide a position sense voltage
to the seat motor potentiometers and the mirror
rheostat(s). This voltage can be checked at the appro-
priate cavities of the 21 and 25-way connectors.
²Verify the switch connector is mated with the
seat switch on the inside of the outboard side-shield.
²Verify battery voltage at the P9 circuit refer-
enced to the Z1A ground reference (cavity 1) of the
seat switch. If P9 low current battery is not available
Fig. 6 Memory Seat/Mirror Module 25-Way Connector
8R - 8 POWER SEATSNS
DIAGNOSIS AND TESTING (Continued)
coming from the module, replace the Memory Seat/
Mirror Module.
²If P9 low current battery is present at (cavity 5)
referenced to ground Z1 (cavity 1) of the seat switch,
verify the presence of the P9 voltage at the switch
outputs. If there is no output voltage from the
switch, replace the switch.
²If P9 voltage is present at the output of the
switch, but there is no reaction from the memory
seat/mirror module, verify that the P9 voltage is
present at the appropriate 21-way connector pins
into the module. If the P9 voltage is not present at
the 21-way connector, repair or replace the seat wir-
ing harness. If the verification check of the seat wir-
ing harness is correct, replace the control module.
(2) If the control module does not respond with a
relay click to a specific seat switch when actuated,
verify the continuity of the particular circuit between
the seat switch and the Memory Seat/Mirror Module.
If the P9 voltage is present at the correct input of the
21-way connector of the module when the switch is
actuated, but there is no response by the module,
replace the Memory Seat/Mirror Module.
(3) If the Memory Seat/Mirror Module responds
with a relay click when a seat switch is actuated for
a given direction, but there is no reaction from a seat
or recliner motor relating to that switch input, dis-
connect the 10-way connector from the control mod-
ule. Jumper the battery and ground from cavities 8
and 7 of the seat harness 10-way connector to the
proper cavities for the seat or recliner motor in ques-
tion and direction of travel desired. If the motor oper-
ates, replace the control module. If the motor does
not operate, verify continuity of the wiring into the
motor 2-way connector. Repair or replace the wiring
as necessary. If the wiring has continuity, and the
motor will not operate when fed directly, replace the
track assembly, since the motor/transmission combi-
nations are not designed to be serviced on an individ-
ual basis.
SEAT AND RECLINER POSITION SENSING
Seat and recliner position sense ground reference
circuit P28 BR/RD feed is from the memory seat/mir-
ror module (cavity 10) 21-way connector to each of
the position sense connectors.
Seat and recliner position sense +5 volt feed circuit
P29 BR/WT feed is from the memory seat/mirror
module (cavity 20) 21-way connector to each of the
position sense connectors.
To test for the presence of a sense voltage, a volt
meter must be used as follows:
²Connect the negative probe to the P28 circuit
(cavity 10) of the 21-way connector.
²Connect the positive probe to the P29 circuit
(cavity 20) of the 21-way connector and verify a volt-age reading between 3.5 and 5 volts when a seat or
recliner switch is activated.An internal timer in
the Memory Seat/Mirror Module (MSM Module)
regulates the length of time this voltage stays
active i.e., 3 seconds from the time that the
switch was activated, unless the switch is held
or while the transmission is out of PARK.If the
voltage is less than 3.5, there is a fault in the system
that is drawing it down. To troubleshoot this circuit,
disconnect the 25-way connector from the MSM Mod-
ule (this removes all of the vehicle mirror circuitry).
If the voltage is still less than 3.5, disconnect each of
the position sense connectors from each of the
motors. If the voltage remains less than 3.5, replace
the MSM Module. If the voltage increases when a
motor is disconnected from the system, determine if
the fault is in the wiring or the motor assembly.
Repair or replace the wire harness assembly as
needed. If the fault is in the motor position sensing
potentiometer, replace the track assembly.
²The potentiometers built onto the motor end-bell
provide voltages to the MSM Module through the
21-way connector, which change as follows, corre-
sponding to the given seat actuations. Refer to Seat
Actuations Table.
SERVICE PROCEDURES
REMOTE KEYLESS ENTRY (RKE) DATA LINK
The memory seat/mirror module interfaces with
the RKE via a serial data link (single wire). The pro-
gramming sequence to relate an RKE transmitter to
the chosen seat, recliner and side view mirror posi-
tions consists of the following steps:
(1) Adjust the seat, recliner and side view mirrors
to the desired position.
(2) Press momentarily and release memory switch
S.
(3) Press momentarily and release memory switch
1or2.
(4) Press momentarily and release a LOCK button
on an RKE transmitter.
(5) To program the second driver's position, follow
the previous sequence with a second transmitter.
(6) To recall either of the programmed positions
with an RKE transmitter, press momentarily and
release an UNLOCK button on one of the pro-
grammed RKE transmitters.An unprogrammed
RKE transmitter will have no effect on the sys-
tem.
(7) The RKE receiver uses the serial data link to
notify the module of a request from a programmed
transmitter, that an UNLOCK button has been
pressed. This UNLOCK request (from a transmitter
associated with either switch 1 or 2) will activate the
NSPOWER SEATS 8R - 9
DIAGNOSIS AND TESTING (Continued)
POWER MIRRORS
CONTENTS
page page
GENERAL INFORMATION
HEATED MIRROR........................ 1
INTRODUCTION......................... 1
MEMORY MIRRORS...................... 1
DIAGNOSIS AND TESTING
HEATED MIRROR TEST................... 1MIRROR MOTOR TEST................... 1
MIRROR SWITCH TEST................... 1
REMOVAL AND INSTALLATION
POWER MIRROR SWITCH................. 3
POWER MIRROR........................ 3
GENERAL INFORMATION
INTRODUCTION
Electrically-operated remote control mirrors are
controlled by a switch assembly located on the head-
lamp switch bezel in the instrument panel.
The vehicle uses a rocker switch for right or left
side mirror selection and a single platform button for
mirror UP, DOWN, RIGHT, or LEFT movement.
The motors which operate the mirrors are part of
the mirror assembly and cannot be serviced sepa-
rately.
HEATED MIRROR
Heated mirrors are available on models with
Power Mirrors and Rear Window Defogger only. The
heated mirror is controlled by the rear window defog-
ger switch. The heated mirror is ON when the rear
window defogger is ON.
MEMORY MIRRORS
For memory mirrors refer to Group 8R, Power
Seats section Memory Seat/Mirror system.
DIAGNOSIS AND TESTING
MIRROR MOTOR TEST
(1) Remove headlamp switch bezel. Refer to Group
8E, Instrument Panel and Gauges.
(2) Disconnect wiring harness connector to the
power mirror switch and headlamp switch.
(3) Using two jumper wires:
²Connect one to a 12-volt source
²Connect the other to a good body ground
²Refer to the Mirror Test Chart for wire hookups
at the switch connector (Fig. 1).(4) If results shown in chart are not obtained,
check for broken or shorted circuit, or replace mirror
assembly as necessary.
MIRROR SWITCH TEST
(1) Remove power mirror switch from mounting
position.
(2) Disconnect wiring harness at switch connector.
(3) Using a ohmmeter, test for continuity between
the terminals of the switch as shown in the Mirror
Switch Continuity Chart (Fig. 2).
(4) If results shown in the chart are not obtained,
replace the switch.
HEATED MIRROR TEST
Heated mirrors are available on models with
Power Mirrors and Rear Window Defogger only. The
heated mirror is controlled by the rear window defog-
ger switch. The heated mirror is ON when the rear
window defogger is ON.
TEST PROCEDURE
(1) The mirror should be warm to the touch.
(2) If not, check the 10 amp fuse (12) in the junc-
tion block behind the instrument panel to the left of
the steering column.
(3) Test voltage at rear window defogger switch.
²If no voltage repair wire.
²Apply voltage to one wire and ground the other,
refer to (Fig. 1) for pin numbers. Mirror should
become warm to the touch.
²If not remove mirror glass and test the wires for
continuity. If no continuity repair wires.
²If wires are OK, replace mirror glass.
²To test defogger switch refer to Group 8N, Elec-
trically Heated Systems.
NSPOWER MIRRORS 8T - 1