ECU CHEVROLET DYNASTY 1993 Workshop Manual

INSTALLATION
Reverse the preceding operation.
FRONT SIDE MARKER BULBÐAC/C-BODY
REMOVAL (FIG. 7)
(1) Reach behind the front fender and rotate the
socket counterclockwise. Pull the socket from the
lamp body. (2) Remove the bulb from the socket.
INSTALLATION
Reverse the preceding operation.
FRONT SIDE MARKER LAMPÐAC/C-BODY
REMOVAL (FIG. 7)
(1) Remove the cornering lamp retaining nuts, and
remove cornering lamp. (2) Remove the four nuts retaining the bumper
trim moulding to the body. (3) Remove bumper trim moulding.
(4) Remove side marker lamp.
INSTALLATION
Reverse the preceding operation.
CORNERING LAMP BULB
REMOVAL (FIG. 6 OR 7)
(1) Reach behind the front fender and rotate the
socket assembly counterclockwise. (2) Pull the socket out of the lamp body.
(3) Remove the bulb from the socket.
INSTALLATION
Reverse the preceding operation.
CORNERING LAMP ASSEMBLY
REMOVAL (FIG. 6 OR 7)
(1) Remove the bulb and socket assembly from the
lamp body. (2) Remove nuts securing the lamp assembly to the
cornering lamp bezel. (3) Pull the lamp from the bezel.
INSTALLATION
Reverse the preceding operation.
TAIL, STOP, TURN SIGNAL, BACK-UP
LAMPÐAC/C OR AY/S-BODY
REMOVAL (FIG. 8)
(1) Open trunk lid.
(2) Remove screws holding tail lamp to quarter
panel extension. (3) Separate lamp from vehicle.
(4) Rotate the bulb sockets counterclockwise and
pull the sockets from the lamp. (5) Pull bulb from socket if bulb replacement is re-
quired.
INSTALLATION
Reverse the preceding operation.
TAIL, STOP, TURN SIGNAL, BACK-UP AND SIDE
MARKER LAMPÐAC/D-BODY
REMOVAL (FIG. 9)
(1) Raise deck lid and remove closure panel lower
trim cover. (2) Remove tail lamp attaching wing nuts from be-
hind the rear closure panel.
Fig. 7 Park, Turn Signal, Cornering, and Side Marker LampsÐAC/C or AY/C-S-Body
Fig. 8 Tail, Stop, Turn Signal, Back-Up, and SideMarker LampsÐAC/C or AY/C-S Body
8L - 12 LAMPS Ä

TAIL, STOP, TURN SIGNAL BULB OR LAMP
REMOVAL (FIG. 3)
(1) Open deck lid and remove the plastic wing nut
securing the rear trim cover in place. (2) Pivot the end of the trim panel out of the way
to gain access, and remove three plastic wing-nuts
securing the lamp to the vehicle. (3) Separate the tail lamp from the body far
enough to rotate the socket and bulb assemblies
counterclockwise one-half turn and pull the sockets
out of the lamp body. (4) Remove the bulb from socket.
INSTALLATION
Reverse the preceding operation.
TRUNK LID TAIL LAMP BULB
REMOVAL (FIG. 3)
(1) Remove deck lid liner as necessary. Through
access hole in the inner deck lid, rotate socket coun-
terclockwise one-half turn, and pull the socket and
bulb assembly from the lamp body. (2) Remove the bulb from the socket.
INSTALLATION
Reverse the preceding operation.
TRUNK LID TAIL LAMP
REMOVAL (FIG. 3)
(1) Remove bulb and sockets from trunk lid tail
lamp. (2) Remove six nuts and four screws securing the
tail lamp to the deck lid and remove the lamp assem-
bly from the vehicle.
INSTALLATION
Reverse the preceding operation.
BACK-UP LAMP BULB
REMOVAL (FIG. 3)
(1) From behind the rear bumper fascia, rotate the
bulb and socket assembly counterclockwise one-half
turn and pull the bulb and socket out of the lamp body.
(2) Remove the bulb from the socket.
INSTALLATION
Reverse the preceding operation.
BACK-UP LAMP
REMOVAL (FIG. 3)
(1) Remove the socket and bulb assembly from the
lamp body. (2) Remove two screws from the lamp and pull the
lamp from the rear bumper fascia.
INSTALLATION
Reverse the preceding operation.
REAR SIDE MARKER LAMP BULB
REMOVAL (FIG. 3)
(1) Open the deck lid and remove the fastener
(wing nut) from the lower rear trim panel. Rotate the
inner quarter trim panel forward to gain access to
the lamp assembly. Rotate counterclockwise one-half
turn, and pull the socket and bulb from the lamp
body. (2) Remove the bulb from the socket.
INSTALLATION
Reverse the preceding operation.
REAR SIDE MARKER LAMP
REMOVAL (FIG. 3)
(1) Remove the socket and bulb assembly.
(2) Remove two attaching nuts from the lamp be-
hind the quarter panel and remove the lamp from
the vehicle.
INSTALLATION
Reverse the preceding operation.
LICENSE PLATE LAMP OR BULB
REMOVAL (FIG. 3)
(1) Remove screws holding license plate lamp to
rear bumper fascia.
Fig. 2 Park, Turn Signal, Cornering and Side Marker LampÐTypical
Fig. 3 Tail, Stop, Turn Signal, Back-Up, LicensePlate and Side Marker Lamps
Ä LAMPS 8L - 17

STEERING WHEEL
WARNING: BEFORE BEGINNING ANY AIR BAG
SYSTEM REMOVAL OR INSTALLATION PROCE-
DURES, REMOVE AND ISOLATE THE BATTERY
NEGATIVE (-) CABLE (GROUND) FROM THE VEHI-
CLE BATTERY. THIS IS THE ONLY SURE WAY TO
DISABLE THE AIR BAG SYSTEM. FAILURE TO DO
THIS COULD RESULT IN ACCIDENTAL AIR BAG
DEPLOYMENT AND POSSIBLE PERSONAL INJURY. WHEN AN UNDEPLOYED AIR BAG ASSEMBLY
IS TO BE REMOVED FROM THE STEERING
WHEEL, DISCONNECT BATTERY GROUND CA-
BLE AND ISOLATE. ALLOW SYSTEM CAPACI-
TOR TO DISCHARGE FOR TWO MINUTES.
BEGIN AIR BAG REMOVAL.
REMOVAL
(1) Make sure front wheels are straight, and steer-
ing column is locked in place. (2) Disconnect battery negative cable and isolate.
(3) Wait two minutes for the reserve capacitor to
discharge before removing undeployed module. (4) Remove four nuts attaching air bag module
from the back side of steering wheel. (5) Lift module, and disconnect connector from rear
of module. (6) Remove speed control switch and connector if
so equipped or cover. (7) Remove steering wheel retaining nut.
(8) Remove steering wheel with steering wheel
puller Tool C-3428B.
INSTALLATION
(1) If the clockspring is not properly positioned or if front wheels were moved, follow the clockspring
centering procedure before installing steering wheel.
With the front wheels in the straight ahead position.
Position the steering wheel on the steering column.
Making sure to fit the flats on the hub of the steer-
ing wheel with the formations on the inside of the
clockspring. Pull the air bag and speed control wires
through the lower, larger hole in the steering wheel
and the horn wire through smaller hole at the top.
Make sure not to pinch wires (Fig. 11).
(2) Install retaining nut, and tighten to 61 N Im (45
ft. lbs.) torque. (3) Connect horn wiring lead.
(4) Connect 4-way connector to speed control
switch and attach switch to steering wheel. (5) Connect air bag lead wire to air bag module,
and secure module to steering wheel. (6) Do not connect negative battery cable. Refer to
Air Bag System Check for proper procedure.
STEERING COLUMN SWITCHES
This procedure covers the removal and installation
of the steering wheel and clockspring. Once the
steering wheel and clockspring have been removed,
refer to the appropriate section of this service man-
ual for switch replacement.
WARNING: BEFORE BEGINNING ANY AIR BAG
SYSTEM REMOVAL OR INSTALLATION PROCE-
DURES, REMOVE AND ISOLATE THE BATTERY
NEGATIVE (-) CABLE (GROUND) FROM THE VEHI-
CLE BATTERY. THIS IS THE ONLY SURE WAY TO
DISABLE THE AIR BAG SYSTEM. FAILURE TO DO
THIS COULD RESULT IN ACCIDENTAL AIR BAG
DEPLOYMENT AND POSSIBLE INJURY.
WHEN AN UNDEPLOYED AIR BAG ASSEMBLY
IS TO BE REMOVED FROM THE STEERING
WHEEL, DISCONNECT BATTERY GROUND CA-
BLE AND ISOLATE. ALLOW SYSTEM CAPACI-
Fig. 10 Clockspring (Auto-Locking)
Fig. 11 Steering Wheel Wiring
Ä RESTRAINT SYSTEMS 8M - 7

(6) Steps (3, 4 or 5) above will confirm system op-
eration. Indicator light illumination means that
there is power available at the output of the relay
only, and does not necessarily verify system opera-
tion. (7) If turning the switch ON produced no distinct
current draw on the ammeter the problem should be
isolated in the following manner: (a) Confirm the ignition switch is ON.
(b) Ensure that the heated rear glass feed wire is
connected to the terminal or pigtail and that the
ground wire is in fact grounded. (c) Ensure that the fusible link and control cir-
cuit fuse is operational and all electrical connec-
tions are secure.
(8) When the above steps have been completed and
the system is still inoperative, one or more of the fol-
lowing is defective: (a) Control switch/timer relay module.
(b) All rear window grid lines would have to be
broken or one of the feed wires are not connected
for the system to be inoperative.
(9) If turning the switch ON produces severe volt-
meter deflection, the circuit should be closely
checked for a shorting condition. (10) If the system operation has been verified but
indicator lamp does not light, replace the switch. (11) For detailed wiring information, refer to group
8W, Wiring Diagrams.
GRID TEST
The horizontal grid lines and vertical bus bar lines
printed and fired on inside surface of rear window
glass (Fig. 2) comprise an electrical parallel circuit.
The electrically conductive lines are composed of a
silver-ceramic material which when fired on glass be-
comes bonded to the glass and is highly resistant to
abrasion. It is possible, however, that a break may
occur in an individual grid line resulting in no cur-
rent flow through the line. To detect breaks in grid
lines the following procedure is required: (1) Turn ignition ON and turn control switch to
ON. The indicator light should come on. (2) Using a DC voltmeter with 0-15 volt range,
contact terminal B with negative lead of voltmeter.
With positive lead of voltmeter, contact terminal A
(Fig. 2). The voltmeter should read 10-14 volts. A
lower voltage reading indicates a poor ground con-
nection. (3) With negative lead of voltmeter, contact a good
body ground point. The voltage reading should not
change. (4) Connect negative lead of voltmeter to terminal
B and touch each grid line at Mid-Point with Posi-
tive lead. A reading of approximately 6 volts indi-
cates a line is good. A reading of 0 volts indicates a
break in line between Mid-Point C and terminal A.
A reading of 10-14 volts indicates a break between Mid-Point C and terminal B. Move toward break and
voltage will change as soon as break is crossed (Figs.
2 and 3).
CONTROL SWITCH/TIMER RELAY MODULE TEST
Control switch/timer relay module may be tested
in-vehicle or bench tested. In vehicle testing is ac-
complished in the following manner: (1) Remove the switch, relay assembly from the in-
strument panel or console, see Group 8E, Instrument
Panel and leave the switch connector plugged in. (2) Turn ignition ON.
(3) Using a DC voltmeter, with 0-15 range, check
voltage at terminals B, I and L. (Figs. 3 and 4). Ter-
minals B and I should confirm a voltage of 10 to 14
volts to ground when the ON switch is pressed. Ter-
minal L should confirm voltage to ground. When ter-
minals B and I show no voltage, trace circuit
upstream of switch/relay module for problem (wiring
cut, fusible link or circuit breaker inoperative, bulk-
head connector not operative, etc.) If terminal L in-
dicates voltage, place switch in Off position. If
voltage at L is still indicated or indicator lamp re-
mains on, the switch/relay module should be re-
placed. (4) If the relay checks out to this point, momen-
tarily operate switch to ON position. The indicator
lamp should come on and remain on for approxi-
mately 10 minutes. Terminal L should confirm volt-
age. If the indicator lamp fails to light or voltage at
terminal L is not confirmed the switch/relay module
should be replaced.
Fig. 3 Systems Electrical Circuit
8N - 2 REAR WINDOW DEFOGGER Ä

ELECTRIC MOTOR TEST
Make certain battery is in normal charged condi-
tion before circuits are tested. To determine which motor is faulty, check each in-
dividual door for electrical lock and unlock or discon-
nect the motor connectors one at a time, while
operating the door lock switch. In the event that
none of the motors work, the problem maybe caused
by a shorted motor, or a bad switch. Disconnecting
the defective motor will allow the others to work. The power lock motors are also equipped with a
thermal protection system which prevents the motors
from burning out. The motors may chatter if they are
continuously activated. To test an individual door lock motor, disconnect
the wire connector at the motor (Fig. 2 and 3). Test
at the connector for 12 volts while applying door lock
switch. If no voltage repair wire. Apply 12 volts to
the motor terminal, and a known good ground to the
other terminal to check motor operation. Should the motor defect be a result of a broken
wire, it should have no effect on the operation of the
other motors.
POWER DOOR LOCKS
When AC, AG, AJ or AY Body vehicles are
equipped with power door locks, the system includes
an automatic door locking feature which is actuated
through the vehicle's body controller. When this system is enabled the automatic door
locks will work automatically. When the system is
disabled the door locks will work by use of the door
lock switches only. The body controller controls the power locks when
the door lock switch is activated. If the door lock switch is pressed for longer than eight consecutive
seconds, the body controller will de-energize the door
lock relay. Also, the body controller will automati-
cally lock all doors when all of the conditions below
are met:
² All doors are closed
² The vehicle speed exceeds 15 61 MPH
² The throttle position sensor tip-in is greater than
10 62 degrees
The DRB II must be used to enable/disable the au-
tomatic door lock system. Refer to the Body Diagnos-
tic Procedures Manual for the procedure. The body controller will automatically re-lock all
doors if the above conditions are met and if any of
the doors become ajar. The body controller does not
control the door unlock function. The switch is wired
directly to the lock relay.
Fig. 1 Door Lock Switch Continuity
Fig. 2 Door Lock Motor
Fig. 3 Door Latch with Lock MotorÐAC and AY Bodies
8P - 2 POWER LOCKS Ä

to the deck lid open position. If the pull down limit
switch is depressed at this time, the motor should
stop.(c) If these results are not obtained, replace the
pull down motor assembly.
REMOTE KEYLESS ENTRY
OPERATION
The transmitter has three buttons for operation
(Fig. 11).
² UNLOCK driver's door, enable illuminated entry,
and disarm the Theft Security System. Pushing and
releasing the button once will unlock the driver's
door. Two times within five seconds all doors will un-
lock.
² LOCK all doors, set Theft Security System and
chirp horn. Chirp of horn is a short toot to notify
that the alarm system is set and the indicator lamp
on the instrument panel will flash for about 15 sec-
onds.
² Unlock Trunk Lid
² The receiver is capable of retaining VAC even
when power is removed.
² Each receiver must have at least one and no more
than two transmitters.
CONTROL RANGE
Operation range is within 7 meters (23 ft.) of the
receiver.
TRANSMITTER BATTERY
The battery can be removed without special tools
and are readily available at local retail stores. The
recommended battery is Duracell DL 2016 or equiv-
alent. Battery life is about one to two years.
PROGRAM REMOTE KEYLESS ENTRY
(1) Remove trim cover or floor console as needed
that may be covering the Air Bag System Diagnostic
Module (ASDM). (2) Pull floor carpeting back between the accelera-
tor peddle and ASDM. (3) Locate program line a dark green wire with a
insulator on the end. Located between the accelerator
and (ASDM). (4) Turn ignition switch to the ON position.
(5) Connect the program line from the Remote
Keyless Entry Module to ground. The door locks will
lock and unlock to indicate the receiver is ready to
receive transmitter code. Trunk solenoid will not cy-
cle. (6) Press any button on the transmitter to set code.
If there is a second transmitter it has to be set at
this time. The locks will cycle to confirm program-
ming. (7) Disconnect the program line from ground. This
returns the system to its normal operation mode. (8) Replace trim cover or floor console as neces-
sary.
HORN CHIRP CANCELLATION
During the programming operation the horn chirp
can be disabled using the following procedures: (1) Remove trim cover or floor console as needed
that may be covering the Air Bag System Diagnostic
Module (ASDM). (2) Pull floor carpeting back between the accelera-
tor peddle and ASDM. (3) Locate program line a dark green wire with a
insulator on the end. Located between the accelerator
and (ASDM). (4) Turn ignition switch ON.
(5) Connect the program line from the Remote
Keyless Entry Module to ground. The door locks will
lock and unlock to indicate the receiver is ready to
receive transmitter code. Trunk solenoid will not cy-
cle. (6) Press any button on the transmitter to set code.
If there is a second transmitter it has to be set at
this time. The locks will cycle to confirm program-
ming. (7) Press LOCK then UNLOCK transmitter but-
tons repeat three times. (8) Door locks and rear release will cycle three
times as feedback of Horn Chirp lockout. (9) Remove ground from program line to restore
normal system operation. (10) To reinstate the Horn Chirp feature refer to
Program Remote Keyless Entry.
TESTING
CONDITION: When trying to program the receiver
module in the vehicle with a new transmitter and
there is no response from the module, Example: the
door locks do not cycle through a lock/unlock routine.
Refer to Fig. 12 for a block wiring diagram or to
Group 8W, Wiring Diagrams.
Fig. 11 Transmitter
Ä POWER LOCKS 8P - 5

(1) Be sure that the module has a battery feed
from the 20 Amp breaker in cavity 1 of the black
connector. Also affected would be the optical horn
and the stop lamps. (2) Be sure that the module has an ignition feed
from 5 Amp fuse in cavity 8 of the black connector.
Also affected would be the body computer, instru-
ment cluster and message center. (3) Be sure that the module has a ground from the
right side cowl behind the body computer to the cav-
ity 5 of the black connector. (4) Be sure that you are supplying a good ground
to the programming wire. (5) If the above circuits are good, replace the Re-
ceiver Module. CONDITION: Doors can be locked or unlocked with
the Keyless Entry transmitter. But the doors will not
lock. The Vehicle Theft Alarm system will not arm,
when using only the power door LOCK switch in the
driver's door. (1) Be sure you have not left key in the ignition
column lock cylinder. (2) If step 1 is OK, check the Key in Lock switch
circuit in the steering column for a short to ground. (3) In this problem the body computer controls the
LOCK function. Be sure that it is providing a battery
voltage output to the door lock relay. The door lock
relay controls the door lock motors. CONDITION: Doors will lock but Vehicle Theft
System will not arm when using the transmitter. (1) The Keyless Entry Receiver Module controls
the door lock signal to the door lock relay. The door
lock relay controls the door lock motors. Check for
battery voltage at cavity 10 of the Theft Alarm mod-
ule from the Receiver module. (2) If voltage is OK, replace Receiver module.
CONDITION: All doors except driver's door will
lock with the transmitter. (1) Test the driver's door output of the Receiver
Module for a ground. (2) If there is no ground at the pin, replace the Re-
ceiver module. (3) If there is a ground at the output, replace the
door lock motor. CONDITION: Only driver's door will lock with the
transmitter.
² Repair ground circuit to unlock relay
² Replace unlock relay
CONDITION: Doors do not lock with the transmit-
ter, but still get horn CHIRP that indicates that they
did lock. Replace Receiver module. CONDITION: Doors will lock with the transmitter
but there is no horn CHIRP. (1) Press horn button, listen horn sound.
(2) If the horn sounded, change horn relay. (3) Still no CHIRP, check continuity between the
horn relay and the receiver output pin. Repair as
necessary. (4) Still no horn CHIRP, replace the receiver mod-
ule. (5) If using a DRB II, refer to Body Diagnostic Pro-
cedures.
REMOTE KEYLESS MODULE REPLACEMENT
(1) Remove lower right instrument panel silencer.
(2) Remove glove box assembly.
(3) Remove three screws attaching the mounting
bracket to instrument panel. (4) Lower bracket and module assembly, to discon-
nect wire connector. (5) Remove two screws attaching the Remote Key-
less entry Module to bracket. (6) Remove two screws attaching the security mod-
ule to bracket. (7) To installation reverse above procedures.
LAMP OUTAGE MODULE REPLACEMENT
(1) Remove lower right instrument panel silencer.
(2) Remove glove box and ash receiver module.
(3) Remove three screws attaching the mounting
bracket to instrument panel. (4) Lower bracket and module assembly, to discon-
nect wire connectors. (5) Remove two screws attaching the Lamp Outage
Module to bracket. (6) Remove two screws attaching the security mod-
ule to bracket. (7) To installation reverse above procedures.
DOOR LOCK INHIBIT
The power door lock inhibit system prevents the
doors from being locked using the power door locks
when either of two conditions occur: (1) The key is in the ignition switch and any of the
doors are open. The ignition switch does not have to
be ON. (2) The key is in the ignition switch and the head-
lamp are on.
AC, AG, AJ AND AY BODIES
With the ignition switch in the ON or OFF position
and the driver's door open the Body Controller will
ignore the command to lock the power door locks.
Once the key is removed, or the driver's door is
closed, the Body Controller will allow the power door
locks to lock. Refer to Body Diagnostic Procedure
Manual for further testing procedures.
8P - 6 POWER LOCKS Ä

VEHICLE THEFT SECURITY SYSTEM
CONTENTS
page page
GENERAL INFORMATION .................. 1
SECURITY SYSTEM DOOR SWITCH REPLACEMENT ........................ 2
SECURITY SYSTEM HOOD SWITCH REPLACEMENT ........................ 2 SYSTEM SELF-TESTS
.................... 1
VEHICLE THEFT SECURITY SYSTEM MODULE REPLACEMENT ........................ 2
WHAT WILL TRIGGER THE SYSTEM ........ 1
GENERAL INFORMATION
JUMP-STARTING, VEHICLE EQUIPPED
WITH THEFT SECURITY SYSTEM . After the
booster battery has been connected, the Theft System
must be turned OFF. Using the key, lock then un-
lock either front door. This turns the Theft System
OFF and the remainder of the Jump-Starting proce-
dure can be followed. If this procedure is not followed, the Theft System
electronics will prevent the engine from starting. If a new Powertrain Control Module is installed,
the engine has to be cranked 20 times before the
alarm system activated. This passive system is designed to protect against
whole vehicle theft. The system monitors vehicle
doors, hood, trunk key cylinder, and ignition action
for unauthorized operation. The alarm activates by
sounding the horn, flashing the park and tail lamps,
and providing an engine kill feature (Fig. 1). Passive arming occurs upon normal vehicle exit,
open door, lock with power locks, close door. The SET
lamp in the panel will flash for 15 seconds, indicat-
ing that arming is in progress. If no monitored sys-
tems are activated during this period, the system
will arm. If the hood or trunk key cylinder switches
are not sensed by the system. The SET lamp will re-
main lit during the arming process, although the sys-
tem will still arm. The system is to be considered as
an active armed system when using the Remote Key-
less Entry. If the SET lamp does not illuminate at all
upon door closing it indicates that the system is not
arming. Passive disarming occurs upon normal vehicle en-
try unlocking either door with the key, or unlocking
using the Remote Keyless transmitter. This disarm-
ing will also halt the alarm once it has been acti-
vated. Whenever the battery is disconnected and recon-
nected, the Vehicle Theft Security System enters
power up alarm mode which flashes the park and tail
lamps and prevents the engine from running. To exit
this mode, the system must be disarmed as men-
tioned above. A tamper alert exists to notify the driver that the
alarm had been activated, and the alarm has since
timed-out for more than 18 minutes. This alert con-
sists of 3 horn pulses when the vehicle is disarmed. The alarm system will not arm if the doors are
manually locked, providing a manual override of the
alarm.
WHAT WILL TRIGGER THE SYSTEM
One of the following actions will trigger the system
while it is armed. Without properly disarming sys-
tem, by using the key or the remote transmitter. (1) Opening the HOOD.
(2) Opening any DOOR.
(3) Removing the TRUNK KEY CYLINDER.
(4) Turning the IGNITION ON.
(5) The ignition switch can be turned to the acces-
sory position without triggering alarm system.
SYSTEM SELF-TESTS
A diagnostics mode is available in the system to
verify operation of all monitored switches or circuits.
To enter diagnostics, cycle the ignition key to the ac-
cessory position 3 times, leaving the key in this po-
sition. Upon entering diagnostics, the park and tail lamps
will begin flashing to verify their operation. In addi-
tion, the horn will sound twice to indicate that the
trunk key cylinder is in its proper position. Return-
ing the ignition to the OFF position will stop the
lamps from flashing while keeping the system in di-
agnostics. While in diagnostics mode, a horn pulse should oc-
cur at each of the following events indicating proper
operation: (1) Beginning with all doors closed, open then close
each door. The horn will sound when the door ajar
switch closes, and then again when the switch opens.
There must b e a 1 second delay between closing and
opening the switch. (2) Open, then close the hood. The horn will sound
when the hood is opened, and again when it is closed.
Ä VEHICLE THEFT SECURITY SYSTEM 8Q - 1

(3) Activate the power door locks in both the
LOCK and UNLOCK directions. The horn will sound
after each activation. (4) Rotate the key in each of the door lock cylin-
ders to the unlock position. The horn will sound as
the switch closes, and again when it opens. There
must b e a 1 second delay between changing switch
states, or the horn will not sound.
² Press the LOCK button,horn will sound.
² Press the UNLOCK button, horn will sound.
(5) Cycle the key to the ignition RUN position. A
single horn pulse will indicate proper operation of
the ignition input. This will also take the module out
of the diagnostics mode. For any of these tests, if the
switch does not remain open or closed for at least 1
second, the horn will only sound once. The lack of a horn pulse, during any operation, in-
dicates a switch failure. Check for continuity at the
switch, if this is good, check for an open or shorted
wire between the switch and alarm module. Also,
check if a new powertrain control module has been
installed recently. Vehicle Theft Security System will
not function until 20 engine cranks. Whenever a Vehicle Theft Security System mal-
function occurs, first verify that the wire harness is
properly connected to all connectors before starting
normal diagnosis and repair procedures. Refer to Ve-
hicle Theft Security System Diagnosis Chart (Fig. 3).VEHICLE THEFT SECURITY SYSTEM MODULE
REPLACEMENT
If the Vehicle Theft Security System module is be-
ing removed and no replacement module is being in-
stalled, the module wiring must be disconnected
while the engine is running. Failure to do so will
cause a no-start condition (Fig. 3 and 4). (1) Remove lower right instrument panel silencer.
(2) Remove glove box assembly.
(3) Remove three attaching screws mounting the
bracket to instrument panel. (4) Lower bracket and module assembly, to discon-
nect wire connectors. (5) Remove the Remote keyless module so to have
access to the Security Module two screws attaching
module to bracket. (6) For installation reverse above procedures.
SECURITY SYSTEM HOOD SWITCH REPLACEMENT
(1) Remove screw from left inner fender (Fig. 5).
(2) Disconnect wiring.
(3) Remove switch.
(4) For installation reverse above procedures.
SECURITY SYSTEM DOOR SWITCH REPLACEMENT
(1) Remove door trim panel and water shield. Re-
fer to Group 23, Body.
Fig. 1 Vehicle Theft Security System Components
8Q - 2 VEHICLE THEFT SECURITY SYSTEM Ä

Fig. 2 Vehicle Theft Security System Diagnosis
Ä VEHICLE THEFT SECURITY SYSTEM 8Q - 3