wheel CHRYSLER VOYAGER 1996 Service Manual

TEST 2
Test 2 checks the antenna for an open circuit as
follows:
(1) Unplug the antenna coaxial cable connector
from the radio chassis.
(2) Connect one ohmmeter test lead to the tip of
the antenna mast. Connect the other test lead to the
center pin of the antenna coaxial cable connector.
(3) Continuity should exist (the ohmmeter should
only register a fraction of an ohm). High or infinite
resistance indicates damage to the base and cable
assembly. Replace the faulty base and cable, if
required.
TEST 3
Test 3 checks the condition of the vehicle body
ground connection. This test should be performed
with the battery positive cable removed from the bat-
tery. Disconnect both battery cables, the negative
cable first. Reconnect the battery negative cable and
perform the test as follows:
(1) Connect one ohmmeter test lead to the vehicle
fender. Connect the other test lead to the battery
negative post.
(2) The resistance should be less than (1) ohm.
(3) If the resistance is more than (1) ohm, check
the braided ground strap connected to the engine and
the vehicle body for being loose, corroded, or dam-
aged. Repair the ground strap connection, if required.
TEST 4
Test 4 checks the condition of the ground between
the antenna base and the vehicle body as follows:(1) Connect one ohmmeter test lead to the vehicle
fender. Connect the other test lead to the outer crimp
on the antenna coaxial cable connector.
(2) The resistance should be less then (1) ohm.
(3) If the resistance is more then (1) ohm, clean
and/or tighten the antenna base to fender mounting
hardware.
AUDIO SYSTEM
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, REFER TO GROUP 8M - PASSIVE
RESTRAINT SYSTEMS BEFORE ATTEMPTING ANY
STEERING WHEEL, STEERING COLUMN, OR
INSTRUMENT PANEL COMPONENT DIAGNOSIS OR
SERVICE. FAILURE TO TAKE THE PROPER PRE-
CAUTIONS COULD RESULT IN ACCIDENTAL AIR-
BAG DEPLOYMENT AND POSSIBLE PERSONAL
INJURY.
RADIO
If the vehicle is equipped with remote radio
switches located on the backs of the steering wheel
spokes, and the problem being diagnosed is related to
one of the symptoms listed below, be certain to check
the remote radio switches and circuits as described
in this group, prior to attempting radio diagnosis or
repair.
²Stations changing with no remote radio switch
input
²Radio memory presets not working properly
²Volume changes with no remote radio switch
input
²Remote radio switch buttons taking on other
functions
²CD player skipping tracks
²Remote radio switch inoperative.
For circuit descriptions and diagrams, refer to
Group 8W - Wiring Diagrams.
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, REFER TO GROUP 8M - PASSIVE
RESTRAINT SYSTEMS BEFORE ATTEMPTING ANY
STEERING WHEEL, STEERING COLUMN, OR
INSTRUMENT PANEL COMPONENT DIAGNOSIS OR
SERVICE. FAILURE TO TAKE THE PROPER PRE-
CAUTIONS COULD RESULT IN ACCIDENTAL AIR-
BAG DEPLOYMENT AND POSSIBLE PERSONAL
INJURY.
CAUTION: The speaker output of the radio is a
ªfloating groundº system. Do not allow any speaker
lead to short to ground, as damage to the radio
may result.
Fig. 7 Antenna Tests
8F - 4 AUDIO SYSTEMSNS
DIAGNOSIS AND TESTING (Continued)

(1) Check the fuse(s) in the junction block and the
Power Distribution Center (PDC). If OK, go to Step
2. If not OK, repair the shorted circuit or component
as required and replace the faulty fuse(s).
(2) Check for battery voltage at the fuse in the
PDC. If OK, go to Step 3. If not OK, repair the open
circuit to the battery as required.
(3) Turn the ignition switch to the ON position.
Check for battery voltage at the fuse in the junction
block. If OK, go to Step 4. If not OK, repair the open
circuit to the ignition switch as required.
(4) Turn the ignition switch to the OFF position.
Disconnect and isolate the battery negative cable.
Remove the instrument cluster center bezel. Remove
the radio, but do not unplug the wire harness connec-
tors. Check for continuity between the radio chassis
and a good ground. There should be continuity. If
OK, go to Step 5. If not OK, repair the open radio
chassis ground circuit as required.
(5) Connect the battery negative cable. Turn the
ignition switch to the ON position. Check for battery
voltage at the fused ignition switch output circuit
cavity of the left (gray) radio wire harness connector.
If OK, go to Step 6. If not OK, repair the open circuit
as required.
(6) Turn the ignition switch to the OFF position.
Check for battery voltage at the fused B(+) circuit
cavity of the left (gray) radio wire harness connector.
If OK, replace the faulty radio. If not OK, repair the
open circuit to the Ignition-Off Draw (IOD) fuse as
required.
REMOTE RADIO SWITCHES
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, REFER TO GROUP 8M - PASSIVE
RESTRAINT SYSTEMS BEFORE ATTEMPTING ANY
STEERING WHEEL, STEERING COLUMN, OR
INSTRUMENT PANEL COMPONENT DIAGNOSIS OR
SERVICE. FAILURE TO TAKE THE PROPER PRE-
CAUTIONS COULD RESULT IN ACCIDENTAL AIR-
BAG DEPLOYMENT AND POSSIBLE PERSONAL
INJURY.
(1) Disconnect and isolate the battery negative
cable. Wait two minutes for the airbag system capac-
itor to discharge before further service.
(2) Remove the remote radio switch(es) from the
steering wheel.
(3) Use an ohmmeter to check the switch resis-
tance as shown in the Remote Radio Switch Test
table (Fig. 8).
NOTE: The right remote radio switch back is white
in color. The left switch back is black in color. The
right/left remote radio switch orientation is with the
steering wheel installed, and driver in drivers seat.(4) If the switch resistance checks OK, go to Step
5. If not OK, replace the faulty switch.
(5) Check for continuity between the ground cir-
cuit cavity of the switch wire harness connector and
a good ground. There should be continuity. If OK, go
to Step 6. If not OK, repair the open circuit as
required.
(6) Unplug the 24-way white wire harness connec-
tor from the Body Control Module (BCM). Check for
continuity between the radio control circuit cavity of
the remote radio switch wire harness connector and a
good ground. There should be no continuity. If OK, go
to Step 7. If not OK, repair the short circuit as
required.
(7) Check for continuity between the radio control
circuit cavities of the remote radio switch wire har-
ness connector and the BCM wire harness connector.
There should be continuity. If OK, refer to the proper
Diagnostic Procedures manual to test the BCM and
the CCD data bus. If not OK, repair the open circuit
as required.
Fig. 8 Remote Radio Switches
REMOTE RADIO SWITCH TEST
SWITCH POSITION RESISTANCE
VOLUME UP 7320 OHMS
VOLUME DOWN 1210 OHMS
SEEK UP 4530 OHMS
SEEK DOWN 2050 OHMS
PRE-SET STATION ADVANCE 10 OHMS
8F - 6 AUDIO SYSTEMSNS
DIAGNOSIS AND TESTING (Continued)

REMOVAL AND INSTALLATION
ANTENNA MAST AND CABLE LEAD
REMOVAL
(1) Remove glove box from instrument panel, refer
to Group 8E, Instrument Panel and Systems for
proper procedures.
(2) Disconnect antenna cable connector from exten-
sion cable (Fig. 9).
(3) Remove right kick trim panel.
(4) Disengage rubber grommet insulator from door
hinge pillar.
(5) Pull antenna cable through hinge pillar into
open between door hinges.
(6) Hoist and support vehicle on safety stands.
(7) Remove front wheel, refer to Group 22, Wheel
and Tries for proper procedures and tightening refer-
ences.
(8) Remove front wheelhouse splash shield, refer
to Group 23, Body for proper procedures.
(9) Slide the plastic sleeve up on antenna mast for
access to mast. Remove antenna mast from antenna
base (Fig. 10).
(10) Remove plastic cap from the cap nut. Using
cap nut tool, remove cap nut holding antenna base to
front fender (Fig. 11).
(11) Remove antenna base from under front fender.
INSTALLATION
For installation, reverse the above procedure.
ANTENNA EXTENSION CABLE
REMOVAL
(1) Remove glove box.
(2) Disconnect extension cable end from antenna
cable end (Fig. 9).
(3) Disconnect cable hanger clip from HVAC unit.
(4) Remove radio as necessary to gain access to
extension cable.
(5) Disconnect extension cable from back of radio.
(6) Remove extension cable from vehicle.
INSTALLATION
For installation, reverse the above procedure.
Fig. 9 Antenna Cable
Fig. 10 Antenna Mast
NSAUDIO SYSTEMS 8F - 7

FRONT DOOR SPEAKER
REMOVAL
(1) Remove front door trim panel as necessary to
gain access to door speaker. Refer to Group 23, Body
for proper procedures.
(2) Remove screws holding speaker to bracket (Fig.
16).
(3) Remove speaker from bracket.
(4) Disconnect wire connector from speaker.
(5) Remove speaker.
INSTALLATION
For installation, reverse the above procedure.
REMOTE RADIO SWITCHES
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, REFER TO GROUP 8M - PASSIVE
RESTRAINT SYSTEMS BEFORE ATTEMPTING ANY
STEERING WHEEL, STEERING COLUMN, OR
INSTRUMENT PANEL COMPONENT DIAGNOSIS OR
SERVICE. FAILURE TO TAKE THE PROPER PRE-
CAUTIONS COULD RESULT IN ACCIDENTAL AIR-
BAG DEPLOYMENT AND POSSIBLE PERSONAL
INJURY.
REMOVAL
(1) Disconnect and isolate the battery negative
cable. Wait two minutes for the airbag system capac-
itor to discharge before further service.
(2) From the underside of the steering wheel,
remove the (3) bolts that secure the driver side air-
bag module to the steering wheel.
(3) Pull the airbag module away from the steering
wheel far enough to access the wire harness connec-
tors on the back of the airbag module.
(4) Unplug the airbag module and horn switch
wire harness connectors from the back of the airbag
module.
(5) Remove the driver side airbag module from the
vehicle.
(6) Remove the steering wheel from the steering
column. Refer to Group 19±Steering, for service pro-
cedure.
(7) Unplug the wire harness connector from the
remote radio switch (s).
(8) Remove three screws securing steering wheel
rear cover. Refer to Group 19, Steering for serivce
procedure.
(9) Remove the remote radio switch from the steer-
ing wheel by depressing tabs on each side of switch..
NOTE: The right remote radio switch back is white
in color. The left switch back is black in color. The
right/left remote radio switch orientation is with the
steering wheel installed, and driver in drivers seat.
INSTALLATION
For installation, reverse the above procedure. The
switches can only be installed one way. Be careful to
index them correctly before pressing them into place.
Tighten the airbag module mounting screws to 10.2
N´m (90 in. lbs.).
Fig. 15 Right Instrument Panel Speaker
Fig. 16 Front Door Speaker
NSAUDIO SYSTEMS 8F - 9
REMOVAL AND INSTALLATION (Continued)

HORNS
CONTENTS
page page
DESCRIPTION AND OPERATION
INTRODUCTION......................... 1
DIAGNOSIS AND TESTING
HORN RELAY........................... 1
HORN SYSTEM.......................... 3
HORN SYSTEM TEST..................... 3HORN................................. 1
HORNS SOUND CONTINUOUSLY............ 3
HORNS WILL NOT SOUND................ 2
REMOVAL AND INSTALLATION
HORN SWITCH.......................... 4
HORNS................................ 4
DESCRIPTION AND OPERATION
INTRODUCTION
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAG, SEE GROUP 8M, RESTRAINT SYSTEMS FOR
SAFETY PRECAUTIONS. DISCONNECT THE NEGA-
TIVE CABLE FROM THE BATTERY BEFORE SER-
VICING COMPONENTS INVOLVING THE AIRBAG
SYSTEM. ACCIDENTAL DEPLOYMENT OF AIRBAG
AND PERSONAL INJURY CAN RESULT.
The horn circuit consists of a horn switch, clock-
spring, horn relay, horns and Body Control Module
(Fig. 1). The horn switch is a membrane switch
located in the airbag cover. The horns are located for-
ward of the left front wheel behind the bumper fas-
cia. The horn relay plugs into the junction block. For
circuit information and component locations refer to
Group 8W, Wiring Diagrams.
DIAGNOSIS AND TESTING
HORN
(1) Disconnect wire connector at horn.
(2) Using a voltmeter, connect one lead to ground
terminal and the other lead to the positive wire ter-
minal (Fig. 3).
(3) Depress the horn switch, battery voltage
should be present.
(4) If no voltage, refer to Horn Will Not Sound. If
voltage is OK, go to step Step 5.
(5) Using ohmmeter, test ground wire for continu-
ity to ground.
(6) If no ground repair as necessary.
(7) If wires test OK and horn does not sound,
replace horn.
HORN RELAY
(1) Remove horn relay.
(2) Using ohmmeter, test between relay connector
terminals 85 to 86 for 70 to 75 ohms resistance (Fig.
2). If resistance not OK, replace relay.
(3) Test for continuity between ground and termi-
nal 85 of horn relay.
(a) When the horn switch is not depressed, no
continuity should be present.
(b) Continuity to ground when horn switch is
depressed.
(c) If continuity is not correct repair horn
switch or wiring as necessary, refer to Group 8W,
Wiring Diagrams Group 8M Restraint System for
Driver's Airbag Module removal procedures.
(4) Using voltmeter, test voltage at:
(a) Terminals 30 and 86 of the horn relay to
body ground.
(b) If NO voltage check fuse 7 of the BCM.
(c) If incorrect voltage repair as necessary. Refer
to Group 8W, Wiring Diagrams.
(5) Insert a jumper wire between terminal 30 and
87 of the power distribution center.
(a) If horn sounds replace relay.
Fig. 1 Horn System
NSHORNS 8G - 1

(b) If the horn does not sound, install horn relay
and refer to Horn Test.
HORNS WILL NOT SOUND
Check horn fuse 6 in the Power Distribution Cen-
ter and fuse 7 in the Junction Block. If fuse is blown
refer to FUSE BLOWN section. If fuse is OK, refer to
FUSE OK section.
FUSE BLOWN
(1) Verify condition of battery terminals and volt-
age, refer to Group 8A, Battery. If battery connec-
tions and battery charge is OK proceed to Step 2.
(2) Using a voltmeter, test for battery voltage at
both sides of horn fuse 7. If voltage is OK, on both
sides of fuse, proceed to Fuse OK. If voltage is OK,
on one side of fuse, the fuse is blown, proceed to Step
3.
(3) Using a suitable ammeter in place of the fuse,
test amperage draw of the horn circuit. If amperage
draw is greater than 20 amps without the horn
switch depressed, a grounded circuit exists between
the fuse and the horn relay. Proceed to Step 4. If
amperage draw is greater than 20 amps with the
horn switch depressed, a grounded circuit exists
between the horn relay and the horn. Proceed to step
Step 5.
(4) Remove the horn relay from the Junction
Block. If the amperage draw drops to 0 amps, the
horn switch or circuit is shorted. Refer to group 8W,
Wiring Diagrams for circuit information. If the
amperage draw does not drop to 0 amps, repair short
at the Junction Block.
(5) Disengage a wire connector from one of the
horns. If amperage drops and the connected horn
sounds, replace the faulty horn. If amperage does not
drop with both horns disconnected and the horn
switch depressed, proceed to Step 6.
(6) Using a continuity tester, with the horns dis-
connected test continuity of the X2 cavity of the horn
relay to ground. Refer to Group 8W, Wiring Diagrams
for circuit information. If continuity is detected, the
circuit is grounded between the Junction Block and
the horns. Locate and repair pinched harness.
FUSE OK
(1) Remove the horn relay from the Junction
Block.
(2) Using a continuity tester, Depress horn switch
and test continuity from the X3 cavity of the horn
relay to ground. Refer to Group 8W, Wiring Diagrams
for circuit information.
(a) If continuity is detected, proceed to Step 3.
(b) If NO continuity, proceed to Step 4.
(3) Using a suitable jumper wire, jump across the
fuse F62 cavity and the X2 cavity of the horn relay in
the Junction Block.
(a) If the horn sounds, replace the horn relay.
(b) If the horn does not sound, proceed to Step 4.
(4) Remove airbag/horn pad from steering wheel.
Refer to Group 8M, Restraint Systems for proper pro-
cedures.
(5) Test continuity across horn switch connectors
with horn switch depressed.
(a) If continuity is detected, repair open circuit
between the relay and the horn switch.
(b) If NO continuity, replace airbag cover.
(6) Install horn relay into Junction Block.
(7) Disengage wire connectors from horns.
(8) Using a voltmeter, with the horn switch
depressed test voltage across horn connector termi-
nals of the wire harness (Fig. 3).
(a) If voltage is detected, replace horns.
(b) If NO voltage, proceed to step Step 9.
(9) With the horn switch depressed, test for volt-
age between the X2 circuit and ground.
(a) If voltage OK, repair system ground at right
cowl area. Refer to Group 8W, Wiring Diagrams.
(b) If NO voltage, repair open X2 circuit between
the relay and the horns.
Fig. 2 Horn Relay
Fig. 3 Horn and Connector
8G - 2 HORNSNS
DIAGNOSIS AND TESTING (Continued)

HORNS SOUND CONTINUOUSLY
CAUTION: Continuous sounding of horns may
cause relay to fail.
The horn switch (membrane) sometimes can be the
cause without the switch being depressing.
(1) Remove the horn relay from the junction block.
(2) Using a continuity tester, test continuity from
the X3 cavity of the horn relay to ground. Refer to
Group 8W, Wiring Diagrams for circuit information.
(a) If continuity is detected, proceed to step Step
3.
(b) If NO continuity, replace the horn relay.
(3) Remove the airbag/horn pad from the steering
wheel and disengage horn connector.
(4) Install horn relay into junction block.
(a) If horn does not sound, replace airbag cover/
horn pad.
(b) If horn sounds, repair grounded X3 circuit
from junction block to clockspring in steering in
steering column. Refer to Group 8W, Wiring Dia-
grams.
HORN SYSTEM
Refer to Horn System Test below. If the horn does
not sound, check horn fuse located in the Power Dis-
tribution Center. If the fuse is blown, replace with
the correct fuse. If the horn fail to sound and the
new fuse blows when depressing the horn switch, a
short circuit in the horn or the horn wiring between
the fuse terminal and the horn is responsible, or a
defective horn switch allowed the horn to burn out is
responsible.
If the fuse is OK, test horn relay refer to Horn
Relay Test.
If the relay is OK, test horn. Refer to Horn System
Test.
CAUTION: Continuous sounding of horn may
cause horn relay to fail.
Should the horn sound continuously:
²Unplug the horn relay from Power Distribution
Center.
²Refer to Horn Relay Test.
Refer to Group 8W, Wiring Diagrams for circuit
and wiring information.
HORN SYSTEM TEST
CONDITION POSSIBLE CAUSE CORRECTION
Horn sounds continuously.
NOTE: Immediately unplug horn
relay in the Power Distribution
Center (PDC)(1) Faulty horn relay.
(2) Horn control circuit to relay
shorted to ground.
(3) Pinched horn switch wire under
Driver Airbag Module.
(4) Defective horn switch(1) Refer to horn relay test.
(2) Check terminal 85 in Junction
Block for continuity to ground. If
continuity to ground indicates:
(a) Steering Wheel horn switch/lead
shorted to ground.
(b) Wiring harness shorted to
ground. Find the short and repair as
necessary.
(3) Replace Driver Airbag Module.
(4) Replace Driver Airbag Module.
Horn sound intermittently as the
steering wheel is turned.(1) Horn relay control circuit X3 is
shorted to ground inside steering
column or wheel.
(2) Pinched horn switch wire under
Driver Airbag Module
(3) Defective horn switch(1) Remove Driver Airbag Module
and/or wheel. Check for rubbing or
loose wire/connector, repair as
necessary.
(2) Replace Driver Airbag Module.
(3) Replace Driver Airbag Module.
Horn does not sound (1) Check fuse 6 in PDC
(2) No Voltage at horn relay
terminals 30 & 86, and fuse is OK.
(3) Open circuit from terminal 85 of
the horn relay to horn switch, X3
circuit.
(4) Defective or damaged horn.
(5) Defective horn switch(1) Replace fuse if blown repair as
necessary.
(2) No voltage, repair the A6 circuit
as necessary.
(3) Repair circuit as necessary.
(4) Voltage at horn when horn switch
is pressed, replace horn.
(5) Replace Driver Airbag Module.
NSHORNS 8G - 3
DIAGNOSIS AND TESTING (Continued)

CONDITION POSSIBLE CAUSE CORRECTION
Fuse blows when horn sounds (1) Short circuit in horn or horn
wiring(1) Remove horn relay, check for
shorted horn or horn wiring.
Disconnect horn wire harness to
isolate short and repair as
necessary.
Fuse blows without blowing horn (1) Short circuit (1) Remove relay, install new fuse, if
fuse does not blow replace horn
relay. If fuse blows with relay
removed, check for short to ground
with ohmmeter on circuit between
terminals 30 & 86 and the fuse
terminal. Repair as necessary.
NOTE: For wiring repairs refer to
Group 8W, Wire Diagrams.
REMOVAL AND INSTALLATION
HORN SWITCH
The horn switch is molded into the airbag cover.
The horn switch cannot be serviced separately. Refer
to Group 8M, Restraint System for Driver Airbag
Module Removal and Installation procedures.
HORNS
REMOVAL
(1) Hoist and support the front of the vehicle on
safety stands.
(2) From behind the front fascia and forward of
the left front wheel, disconnect the wire connectors
from horn.
(3) Remove the mount bracket attaching nut from
the bottom of radiator closure panel. Do not remove
the horn from mounting bracket (Fig. 4).
(4) Separate the horn from vehicle.
INSTALLATION
For installation reverse the above procedures.
Fig. 4 Horn Removal/Installation
8G - 4 HORNSNS
DIAGNOSIS AND TESTING (Continued)

VEHICLE SPEED CONTROL SYSTEM
CONTENTS
page page
GENERAL INFORMATION
INTRODUCTION......................... 1
DESCRIPTION AND OPERATION
AUTOMATIC SPEED CONTROL OVERSPEED
REDUCTION........................... 2
POWERTRAIN CONTROL MODULE.......... 2
SERVO CABLE.......................... 2
SPEED CONTROL SERVO.................. 1
SPEED CONTROL SWITCHES.............. 1
STOP LAMP SWITCH..................... 2
VACUUM RESERVOIR.................... 3
VEHICLE SPEED AND DISTANCE............ 3
DIAGNOSIS AND TESTING
CHECKING FOR DIAGNOSTIC CODES........ 3
ELECTRICAL TESTS AT POWERTRAIN
CONTROL MODULE..................... 6OVERSHOOT/UNDERSHOOT FOLLOWING
SPEED CONTROL SET................... 3
ROAD TEST............................ 3
SERVO VACUUM TEST.................... 6
SPEED CONTROL ELECTRICAL TEST........ 4
SPEED CONTROL SWITCH TEST............ 6
STOP LAMP SWITCH TEST................ 6
VACUUM SUPPLY TEST................... 8
VEHICLE SPEED SENSOR................. 8
REMOVAL AND INSTALLATION
POWERTRAIN CONTROL MODULE.......... 9
SPEED CONTROL CABLE.................. 9
SPEED CONTROL SERVO.................. 8
SPEED CONTROL SWITCHES.............. 9
STOP LAMP SWITCH.................... 9
VACUUM RESEROIR..................... 10
VEHICLE SPEED SENSOR................ 10
GENERAL INFORMATION
INTRODUCTION
The speed control system is electronically con-
trolled and vacuum operated. The electronic control
is integrated into the powertrain control module,
located next to battery. The controls are located on
the steering wheel and consist of the ON/OFF, SET,
RESUME/ACCEL, CANCEL and DECEL buttons
(Fig. 1).
DESCRIPTION AND OPERATION
SPEED CONTROL SERVO
The servo unit consists of a solenoid valve body,
and a vacuum chamber. The PCM controls the sole-
noid valve body. The solenoid valve body controls the
application and release of vacuum to the diaphragm
of the vacuum servo. The servo unit cannot be
repaired and is serviced only as a complete assembly.
SPEED CONTROL SWITCHES
There are two separate switch pods that operate
the speed control system. The steering-wheel-
mounted switches use multiplexed circuits to provide
inputs to the PCM for ON, OFF, RESUME, ACCEL-
ERATE, SET, DECEL and CANCEL modes. Refer to
the owner's manual for more information on speed
control switch functions and setting procedures.
When speed control is selected by depressing the
ON switch, the PCM allows a set speed to be stored
in RAM for speed control. To store a set speed,
depress the SET switch while the vehicle is moving
at a speed between 30 and 85 mph. In order for the
speed control to engage, the brakes cannot be
applied, nor can the gear selector be indicating the
transmission is in Park or Neutral.
The speed control can be disengaged manually by:
²Stepping on the brake pedal
Fig. 1 Speed Control Switches
NSVEHICLE SPEED CONTROL SYSTEM 8H - 1

SERVO VACUUM TEST
(1) Turn ignition switch to the ON position with-
out starting engine. Activate speed control ON
switch.
(2) Disconnect the four-way electrical connector
and the vacuum harness at the servo (Fig. 3).
(3) Connect a jumper wire from Pin 3 of the servo
to Pin 3 of the wire connector.
(4) Ground Pins 2 and 4 in the servo. Do not con-
nect pin 1.
(5) Connect a hand held vacuum pump to the vac-
uum nipple and apply 10 - 15 inches of vacuum.
(6) If servo pulls cable, replace servo.
(7) Ground Pin 1 on servo.
(8) Check that the throttle cable pulls in and holds
as long as the vacuum pump is connected. After one
minute, check if cable is still holding. If cable does
not hold replace the servo.
(9) Disconnect jumper from pin 3. Cable should
return to rest position. If not, replace servo.
(10) Connect 4 way electrical connector and vac-
uum harness to servo.
SPEED CONTROL SWITCH TEST
Refer to the appropriate Powertrain Diagnostic
Manual for switch test valves.
STOP LAMP SWITCH TEST
(1) Remove the stop lamp switch refer to Stop
Switch Removal/Installation in this section. Discon-
nect connector from stop lamp switch (Fig. 4). Using
an ohmmeter, switch continuity may be checked as
follows:
(2) With switch plunger released, there should be
continuity between Pin 5 and Pin 6.(3) With switch plunger depressed, there should be
continuity:
²Between Pin 1 and Pin 2.
²Between Pin 3 and Pin 4.
(4) If the above results are not obtained, the stop
lamp switch is defective or out of adjustment.
(5) Stop lamp switch adjustment is detailed in
Group 5, Brakes.
ELECTRICAL TESTS AT POWERTRAIN CONTROL
MODULE
(1) Unplug the GRAY 40-way connector from the
Powertrain Control Module (PCM), (Fig. 5).
(2) Remove both steering wheel speed control
switches and disconnect the wire connectors.
Fig. 3 Servo Harness Connector
Fig. 4 Stop Lamp Wiring
Fig. 5 Powertrain Control Module Location
8H - 6 VEHICLE SPEED CONTROL SYSTEMNS
DIAGNOSIS AND TESTING (Continued)