battery CHEVROLET DYNASTY 1993 Service Manual

AA BODY
Uses a power door lock inhibit relay. The relay is
located above the glove box compartment.
INHIBIT RELAY
(1) Using a voltmeter, test for battery voltage at
pin 4. If no voltage check fuse 15 (Fig. 13). (2) Using a ohmmeter, check for continuity to
ground at pin 8. If no continuity to ground, check in-
strument panel ground. (3) To check pin 5:(a) The key is in the ignition switch and a door
is open. (b) The key is in the ignition switch and the
headlamps are ON. (c) Test for continuity to ground.
(d) If not, the relay contact is open or the relay is
being energized when it should not be. Pin 5 feeds
the ground from the relay to door lock switch.
(4) To check pin 6: (a) The key is in the ignition switch and a door
is open. (b) The key is in the ignition switch and the
headlamps are ON. (c) Test for continuity to ground.
(d) If not, check key in switch, headlamps on
switch and/or door jamb switches. Pin 6, feeds
ground from key in switch to the relay.
Fig. 13 Inhibit Relay Connector
8P - 8 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

POWER SEATS
CONTENTS
page page
ADJUSTER ............................. 3
CIRCUIT BREAKER TEST .................. 1
ENTHUSIAST SEAT ....................... 4
GENERAL INFORMATION .................. 1
HARNESS VOLTAGE TEST ................. 1
HORIZONTAL AND VERTICAL TRANSMISSIONS ....................... 3
MEMORY CONTROL MODULE REPLACEMENT ....................... 19
MOTOR ................................ 3
MOTOR TESTS .......................... 1
POWER MEMORY SEAT, RECLINER AND MIRRORS ............................. 5 POWER MEMORY SEAT, RECLINER AND
MIRRORS DIAGNOSIS ................... 9
POWER RECLINER MECHANISM ........... 18
POWER RECLINER MOTOR AND CABLE ..... 17
RECLINER SWITCH REPLACEMENT ......... 19
RECLINER SWITCH TEST ................. 19
SEAT ASSEMBLY ........................ 3
SWITCH REPLACEMENT REMOVAL .......... 5
SWITCH TEST ........................... 5
SWITCH TEST ........................... 3
TEST PROCEDURES ...................... 6
TEST PROCEDURES ...................... 1
GENERAL INFORMATION
Power seats can be adjusted in six different direc-
tions up, down, forward, back, tilt forward, or tilt
rearward. A three armature permanent magnet reversible mo-
tor is coupled through cables to worm gear box assem-
blies located in the seat tracks, providing the various
seat movements. The electrical circuit is protected by a 30 amp circuit
breaker located on the fuse block.
TEST PROCEDURES
Before any testing is attempted the battery should be
carefully charged and all connections and terminals
cleaned and tightened to insure proper continuity and
grounds. With dome lamp on, apply switch in direction of
failure. If dome lamp dims the seat motor is trying to
work indicating mechanical jamming. If dome lamp
does not dim, then proceed with the following electrical
tests.
CIRCUIT BREAKER TEST
Find correct circuit breaker on fuse block. Pull out
slightly but be sure that circuit breaker terminals still
contact terminals in fuse block. Connect ground wire of
voltmeter to a good ground. With probe of voltmeter
positive wire, check both terminals of circuit breaker
for battery voltage. If only one terminal checks at
battery voltage, circuit breaker is defective and must
be replaced. If neither terminal shows battery voltage,
check for open or shorted circuit to circuit breaker.
HARNESS VOLTAGE TEST
The following test will determine whether or not
voltage is continuous through the body harness to the
switch. (1) Remove power seat switch from mounting posi-
tion and disconnect switch from wiring harness. (2) Connect one lead of test light to ground terminal,
black wire (BK) of center section, and touch other test
light lead to red wire (RD) terminal. (3) If test light comes on, harness to switch is good.
If test light does not come on, perform circuit breaker
test.
MOTOR TESTS
AA BODY
(1) Remove switch from mounting position and dis-
connect from harness. (2) To check the center motor, connect a jumper wire
between pin 5 and pin 3 (Fig. 1). Connect a second
jumper wire between pin 7 and pin 4 If motor does not
operate, reverse the jumpers, pin 5 to pin 4 and pin 7 to
pin 3. If motor still does not operate check wiring
between switch connector and motor assembly. If wir-
ing checks good replace motor assembly. (3) To check the front motor, connect a jumper wire
between pin 5 and pin 1 (Fig. 1). Connect a second
jumper wire between pin 7 and pin 8. If motor does not
operate, reverse the jumpers, pin 5 to pin 8 and pin 7 to
pin 1. If motor still does not operate check wiring
between switch connector and motor assembly. If wir-
ing checks good replace motor assembly.
(4) To check the rear motor, connect a covered jumper
wire between pin 5 and pin 6 (Fig. 1). Connect a second
Ä POWER SEATS 8R - 1

switch connector and motor assembly. If wiring
checks good replace motor assembly.(4) To check the rear motor, connect a jumper wire
between cavity number 3 and cavity number 4. Con-
nect a second jumper wire between cavity number 6
and cavity number 13. If the motor does not operate,
reverse the jumpers, 3 to 13 and 6 to 4. If the motor
still does not operate check the wiring between
switch connector and motor assembly. If wiring
checks good replace motor assembly. (5) If all motors and the seat operate properly, per-
form Switch Test.
SWITCH TEST
To check the switch, remove the switch from its
mounting position. Using an ohmmeter, perform
switch continuity test (Fig. 5, 6 and 7). If there is no
continuity at any one of the switch positions, replace
the switch.
SEAT ASSEMBLY
REMOVAL
(1) Remove plastic covers.
(2) Remove adjuster attaching bolts and nuts from
floor pan. Move adjuster as required for access. (3) Disconnect battery negative cable.
(4) Disconnect wiring harness power lead at car-
pet. (5) Remove seat assembly from vehicle.
INSTALLATION
(1) Position seat assembly in vehicle.
(2) Connect wiring harness.
(3) Install and tighten mounting bolts and nuts to
28 N Im (250 in. lbs.) torque.
(4) Connect battery negative cable and check seat
operation. (5) Install plastic covers.
HORIZONTAL AND VERTICAL TRANSMISSIONS
Transmissions are not removable and no mainte-
nance is required. If transmission fails replace entire
seat adjuster assembly.
ADJUSTER
REMOVAL
(1) Remove seat assembly from vehicle following
procedure outlined under Seat Assembly Removal. (2) Lay seat on its back on some clean surface.
(3) Remove bolts attaching adjuster to seat assem-
bly (Fig. 8 Through 11). (4) Disconnect wiring harness at switch if seat
mounted switch is used. (5) Remove tie straps holding cable housing to seat
for power bench seat adjuster only.
INSTALLATION
(1) Lay seat on its back on a clean surface.
(2) Position adjuster to seat assembly and install
attaching bolts. (3) Connect wiring harness at switch and replace
tie straps where removed. (4) Install seat following procedure outlined under
Seat Assembly Installation.
MOTOR
REMOVAL
Anytime the motor, cable and housing assemblies,
or vertical and horizontal transmission assemblies,
require maintenance, the assemblies must be syn-
chronized to insure easy and proper operation. (1) Remove seat assembly from vehicle following
procedure outlined under Seat Assembly Removal
(Fig. 8 through 11). (2) Lay seat assembly on its back on a clean sur-
face.
Fig. 3 Left Power Seat SwitchÐAC & AY Bodies
Fig. 4 Right Power Seat SwitchÐAC & AY Bodies
Ä POWER SEATS 8R - 3

SYSTEM SOFT LIMITS
This portion of the system becomes activated when
the control module must shut off a specific seat, re-
cliner or mirror motor because it has reached the end
of its travel. When a mechanical stall condition is de-
tected, the control module will set a soft limit in its
memory and will not allow the motor to be driven
past that point. To override the soft limits, activate the seat or re-
cliner switch twice in the desired direction holding
the switch activated until the end of travel has been
reached. Reactivate and hold the switch once more
for three seconds. This will cause new soft limits to
be set in the control module.
SETTING SYSTEM SOFT LIMITS
If the control module or motor assemblies have
been replaced, the control module must learn its new
soft limits. To do this, perform the memory seat di-
agnostic self-test. After the tests are completed, the
control module will have learned and memorized its
new soft limits.
TEST PROCEDURES
Before any testing is attempted, the battery should
be carefully charged and all connections and termi-
nals cleaned and tightened to insure proper continu-
ity and grounds.
MEMORY SEAT AND MIRROR DIAGNOSTIC
SELF-TESTS
The system has a built-in set of three self-tests
which check all components in the system while giv-
ing a visual feedback. To enter the first self-test mode, switch test, press
memory position 1 and 2 buttons, hold for at least
five seconds and no longer than ten seconds. Follow
this immediately by pressing the Set button and hold
for at least five seconds but less than ten seconds.
Three seconds after the button is released, the seat,
recliner and mirrors will move to a mid-travel posi-
tion. Within ten seconds, press and release a seat
button to activate a seat or recliner motor. All
switches except the mirror switches may now be
tested one at a time. The memory switches, Position
1 and 2 and Set buttons, may also be tested. A good
switch contact actuation will NOD the seat. The seat
nod consists of seat front up and seat track forward
followed by seat front down and seat track rearward.
The nod also includes both outside power rear view
mirrors operating in the vertical plane. The system
will continue NODDING for good switches until 10
seconds pass without any switch actuation. Within 10 seconds of the last seat nod, press mem-
ory position 1 and 2 buttons for at least 5 seconds
Fig. 9 Seat AdjusterÐAA Body
8R - 6 POWER SEATS Ä

above. When the control module has finished, it will
return to the normal operating mode after ten sec-
onds if no further switches are activated.The control module will also return to normal op-
erating mode if any manual seat or recliner move-
ment switch is actuated during the ten second
timeout. If the system has found a problem, refer to the ap-
propriate diagnosis condition.
POWER MEMORY SEAT, RECLINER AND
MIRRORS DIAGNOSIS
Before any diagnosis is done on the system, move
the seat switches and listen for relays clicking in the
control module under the seat. If relays can be heard,
the main battery and ground circuits to the control
module as well as the battery circuit to the switches
in the driver's door are good. When checking for voltage or continuity, always
use a volt/ohm meter to get accurate readings. The
seat and recliner switches must be activated to check
for voltage at the seat and recliner motors or at the
input to the control module from the switches. The control module creates a special voltage supply
for the position sensing functions. It also shuts down
after five seconds, in order to check this or any other
voltage being fed back to the control module. A
switch may have to be activated more than once to
verify a voltage reading. The voltage from the con-
trol module that feeds the seat and recliner position
sensing potentiometer, will be between 4.5 to 5 volts.
For simplicity in the diagnosis section, the feed volt-
age will be called 5 volts. On the position sensing
wires, these voltages will always be less than 5 volts
but more than 0 volts. Typically the high level is at
a maximum of about 4.25 volts and the low level can
be as little as 0.1 volts. If any seat or recliner potentiometer or mirror
rheostat position sense wires are crossed, the control
module will not move that part of the system. The
seat or mirror will be in a fault diagnostic mode.
CONDITION: SYSTEM WILL NOT OPERATE.
PROCEDURE
(1) Check for forward/rearward operation of re-
cliner. If not operable, check for an open or loose cir-
cuit breaker mounted in board on the relay bank in
cavity 15. (2) Check for continuity between 2-way connector
under driver's seat and pin 1 at control module 10-
way connector (Fig. 16 and 17). (3) Check for continuity between 2-way connector
under driver's seat and pin 6 at control module 10-
way connector. (4) Check for any movement of the seat by operat-
ing the seat switch.If movement the circuit is good
into the control module. (5) No movement check for an open or loose fuse in
cavity 15 of the fuse block. (6) Check for battery voltage to pin 3 of driver's
power seat switch.
Fig. 16 Memory Seat Switch Continuity
Fig. 17 Memory Seat Module Connectors
Ä POWER SEATS 8R - 9

(7) If battery is good, check for continuity of driv-
er's power seat switch. Refer to Power Memory Seat
Switch Continuity (Fig. 16). (8) Check that all connectors are securely plugged
into control module under driver's seat with no ter-
minal push outs. (9) No correctable faults are found in the above
steps. The battery voltage and ground circuits are
good into the control module. There is battery volt-
age through the seat switch to the control module.
Then replace the control module. (10) If the control module must be replaced, open it
and observe the non-relay side of the printed circuit
board. The module may be damaged by an intermit-
tent short on the inside of the recliner switch. If a
trace is burnt open near the 10-way connector, may
be caused by the recliner switch (Fig. 18).
(11) If module is burnt, remove recliner switch.
Open the switch and observe the movable contacts
staking at the staked end. If the contact, arm can be
rotated, by a sideways motion, the switch must be re-
placed. This will prevent the new control module
from damaged by the switch.
CONDITION: NO RECLINER MOTION FORWARD OR REARWARD AND NO RELAYSCAN BE HEARD CLICKING WHEN THERECLINER SWITCH IS ACTIVATED.
PROCEDURE
(1) Check for battery voltage at pin 11 of the con-
trol module 21-way connector. (2) Check for battery voltage at pin 3 of the re-
cliner switch connector. (3) Check for ground at pin 1 of the control module
21-way connector. (4) Check for ground at both pins 1 and 5 of re-
cliner switch connector. If ground is missing at only
one of these pins, repair or replace the seat wiring
harness. (5) If battery voltage and ground are correct to the
recliner switch connector, check continuity of the re-
cliner switch. Refer to Left Power Memory Recliner
Switch Continuity (Fig. 19).
CONDITION: NO RECLINER MOTION FORWARD, AND A RELAY CAN BE HEARDCLICKING WHEN THE RECLINER SWITCH ISACTIVATED.
PROCEDURE
(1) Check for battery voltage at pin 2 of the control
module 10-way connector with the recliner switch ac-
tivated. (2) Check for ground at pin 4 of the control module
10-way connector with the recliner switch activated. (3) If battery voltage and ground are NOT present
at the above pins of the 10-way connector, replace
the control module. If battery and ground are
present, then continue procedure. (4) Check for battery voltage and ground at re-
cliner motor connector in seat. (5) If recliner motor will not operate, refer to Ser-
vice Procedure for Recliner Motor and Cable.
CONDITION: NO RECLINER MOTION REARWARD, AND RELAYS CAN BE HEARDCLICKING WHEN THE RECLINER SWITCH ISACTIVATED.
PROCEDURE
(1) Check for ground at pin 2 of the control module
10-way connector with the recliner switch activated.
Fig. 18 Memory Module Burnt Area
Fig. 19 Memory Recliner Switch Continuity
8R - 10 POWER SEATS Ä

(2) Check for battery voltage at pin 4 of the control
module 10-way connector with the recliner switch ac-
tivated. (3) If battery voltage and ground are NOT present
at the above pins of the 10-way connector, replace
the control module. If battery and ground are
present, then continue procedure. (4) Check for battery voltage and ground at re-
cliner motor connector in seat. (5) If recliner motor will not operate, refer to Ser-
vice Procedure for Recliner Motor and Cable.
CONDITION: NO RECLINER MANUAL MOVEMENT FORWARD OR REARWARD,RECLINER MOVES IN RECALL MODE ONLY.
PROCEDURE
(1) Check wiring harness in seat between control
module and recliner switch for shorted wires to
ground or crossed wires. If the ground pins 1 and 5
are in the wrong cavities of the recliner switch con-
nector, the control module may be damaged. Deter-
mine the cause and replace the control module after
repairing the wiring if necessary. (2) The recliner moves forward in the recall mode
only. Press the recliner switch in the forward direc-
tion and check for battery voltage at pin 2 of the re-
cliner switch connector and at pin 5 of the 21-way
control module connector. (3) The recliner moves rearward in the recall mode
only. Press the recliner switch in the rearward direc-
tion and check for battery voltage at pin 4 of the re-
cliner switch connector and at pin 6 of the 21-way
control module connector.
CONDITION: NO RECLINER MOVEMENT IN THE RECALL MODE, RECLINER WILL MOVEMANUALLY WITHOUT STALL DETECTION.
PROCEDURE
(1) Check for 5 volts at pin 9 of the control module
21-way connector (This is the 5 volt feed from the
control module to the recliner position sensing resis-
tor. (2) Check for ground at pin 7 of the 21-way control
module connector. To test for ground, one lead of the
voltmeter must be connected to the 5 volt supply for
the control module. If the sense voltage and ground
are NOT present, at the above pins of the 21-way
control module connector when the recliner switch is
pressed. Replace the control module since an in ad-
vertent application of battery voltage to the circuit
could damaged the control module. If the circuits are
present then continue this procedure. (3) Check for 5 volts at pin 2 of the black 5-way
connector plugged into the recliner motor end-bell. (4) Check for ground at pin 4 of the black 5-way
connector plugged into the recliner motor end-bell. (5) Unplug the black 5-way connector and observe
the male pins for deformation. If deformed, carefully
straighten to mate properly with the connector. Care-
fully reconnect 5-way connector. (6) Check for a voltage at pin 3 of the black 5-way
connector plugged into the recliner motor end-bell
with the recliner switch activated. Less than 5 volts
when fully forward and more than 0 volts when fully
reclined that is variable when the recliner is moving.
This is the position sense voltage the control module
must have or it will not move the recliner in recall
since it has no reference for movement. To test for
this voltage, one lead of the voltmeter must be con-
nected to either pin 4 of the black 5-way connector or
pin 7 of the 21-way connector. If the above steps
have been followed and the voltage is 0, check for a
seat wiring harness short to ground of this circuit,
repair as necessary, before continuing with this pro-
cedure. (7) Check for the position sense voltage at pin 3 of
the control module 21-way connector. If the voltage
appears correct, and varies as indicated in step (6)
above and there is continuity back to the 5-way con-
nector, then replace the control module.
CONDITION: NO SEAT OR RECLINER MOVEMENT FROM THE MANUAL SWITCHES.SEAT AND RECLINER WILL MOVE IN THERECALL MODE ONLY.
PROCEDURE
(1) Check for a stuck switch contact in the recliner
switch mounted in the driver's left seat side shield.
Refer to the Memory Recliner Switch Continuity
(Fig. 19). (2) Check for a stuck switch contact in the driver's
power seat switch. Refer to Memory Seat Switch
Continuity (Fig. 16).
CONDITION: NO MEMORY RECALL OF SEAT, RECLINER, OR MIRRORS. SEAT, RECLINER,AND MIRRORS WILL MOVE BY MANUALSWITCH ACTUATION ONLY.
PROCEDURE
(1) Check for a stuck switch contact in the memory
switch. Refer to the Memory Switch Continuity (Fig.
20). (2) Check for battery voltage pin 1 of the memory
switch (Fig. 20).
Ä POWER SEATS 8R - 11

CONDITION: NO MEMORY RECALL OF SEAT, RECLINER, OR MIRRORS TO POSITION 1ONLY. UNABLE TO ENTER DIAGNOSTIC SELFTEST MODES. POSITION 2 RECALL WORKS.
PROCEDURE
(1) Check for continuity of actuated memory posi-
tion 1 switch. Refer to the Memory Switch Continu-
ity (Fig. 19). If there is continuity, continue with
procedure. If not replace switch. (2) Check for a terminal push out at pin 2 of the
memory switch connector. (3) Check for battery voltage at pin 14 of the con-
trol module 25-way connector with position 1 switch
actuated. If battery voltage is OK. There is no termi-
nal push out, and the connector is properly seated.
But no reaction from the control module, manually
move the seat to a different position than 2. To in-
sure that the Position 1 is not simply a duplicate of
Position 2. If there is still no reaction of the control
module to the actuation of the Position 1 button,
then replace the control module.
CONDITION: NO MEMORY RECALL OF SEAT, RECLINER, OR MIRRORS TO POSITION 2ONLY. UNABLE TO ENTER DIAGNOSTIC SELFTEST MODES. POSITION 1 RECALL WORKS.
PROCEDURE
(1) Check for continuity of actuated memory Posi-
tion 2 button. Refer to the Memory Switch Continu-
ity (Fig. 20). If there is continuity, continue with
procedure. If not replace switch. (2) Check for a terminal push out at pin 3 of the
memory switch connector. (3) Check for battery voltage at pin 1 of the control
module 25-way connector with Position 2 button ac-
tuated. If battery voltage OK. There is no terminal
push out, and the connector is properly seated. But
no reaction from the control module, manually move
the seat to a different position than 1. To insure that
the position 2 is not simply a duplicate of position 1.
If there is still no reaction of the control module to
the actuation of the 2 switch, then replace the con-
trol module.
CONDITION: ACTUATION OF THE SET BUTTON WILL NOT SET ANY NEW POSITIONSIN MEMORY. UNABLE TO ENTERDIAGNOSTIC SELF TEST MODES. ONLYPREVIOUSLY SET MEMORY POSITIONS CANBE RECALLED.
PROCEDURE
(1) Check for continuity of actuated memory
switch Set button. Refer to the Memory Switch Con-
tinuity (Fig. 20). If there is continuity, continue with
procedure. If not replace switch. (2) Check for a terminal push out at pin 4 of the
memory switch connector. (3) Check for battery voltage at pin 2 of the control
module 25-way connector with the Set button actu-
ated. If battery voltage is OK, there is no terminal
push out, and the connector is properly seated then
replace the control module.
CONDITION: NO MEMORY POSITIONS CAN BE RECALLED AND THE MEMORY SEATDIAGNOSTIC SELF SWITCH CHECK IS THEONLY PART OF SELF TEST THAT WORKS.THE SEAT MOVES OK WITH MANUALSWITCH.
PROCEDURE
(1) Check for continuity of the seat belt buckle
switch in its unbuckled state. Operate the buckle
switch to ensure the contact opens when the seat belt
is buckled. (2) Check for continuity between pin 2 of the
2-way seat belt buckle switch connector, harness
side, to ground. (3) Check for continuity between pin 1 of the
2-way seat belt buckle switch connector, harness
side, to pin 13 of the control module 25-way connec-
tor.
CONDITION: MEMORY RECALLS CAN BE MADE WHILE THE VEHICLE IS IN MOTIONWITH THE SEAT BELT UNBUCKLED.
PROCEDURE
Check for continuity of the circuit between the left
side instrument panel blue 16-way connector cav-
Fig. 20 Memory Switch Continuity
8R - 12 POWER SEATS Ä

ity 9 and pin 7 of the control module 25-way connec-
tor. The vehicle speed sensor signal can be tested
with a volt/ohmmeter at pin 7 of the control module
25-way connector. Turn on the vehicle ignition and
check fo r a 5 volt signal as the vehicle is moved
about 3 to 5 feet. If not repair open wiring, terminal
push out, bad crimp, drive in vehicle speed sensor,
etc., as necessary to correct condition. Ensure that
the 25-way connector is plugged into the control
module securely. Road test vehicle after repairs have
been made to ensure that no recalls can occur while
moving.
CONDITION: INSTRUMENT CLUSTER SPEEDOMETER STAYS AT 0 MPH/ (0 KM/H)WHILE VEHICLE IS MOVING, BODYCOMPUTER DOES NOT LOCK DOORS AT 15MPH (24 KM/H), AND THE SPEED CONTROLWILL NOT ACCEPT A SPEED SET.
PROCEDURE
(1) Remove driver's seat anchor bolts and nuts. Ad-
just the driver's seat to a safe driving position. Dis-
connect the 25-way connector from the memory seat
control module. Replace the driver's seat anchor bolts
and nuts. Road test the vehicle to complete this diag-
nosis. If the doors lock, the cruise control accepts a
set, and the speedometer now works, replace the
Memory Seat control module. (2) After replacing the Memory Seat control mod-
ule, perform the memory seat diagnostic self tests.
This teaches the new module it's soft limits and now
re-road test the vehicle before returning it to the cus-
tomer.
CONDITION: NO SEAT MOVEMENT IN THE RECALL MODE, SEAT WILL MOVE BYMANUAL SWITCH ACTUATION IN ALLDIRECTIONS WITHOUT STALL DETECTION.
PROCEDURE
(1) Check for 5 volts at pin 10 of the control mod-
ule 25-way connector. This is the 5 volt feed from the
control module to the seat track position sensing po-
tentiometer. (2) Check for ground at pin 8 of the control module
25-way connector. To test for ground, one lead of the
voltmeter must be connected to either the 5 volt sup-
ply for the control module or the battery positive. If
the sense voltage and ground are NOT present at the
above pins of the 21-way control module connector.
When the seat switch is pressed, replace the control
module. An inadvertent application of battery volt-
age to the circuit could damaged the control module.
If the voltage and ground circuits are present then
continue this procedure. (3) Check for 5 volts at pin 5 of the natural 5-way
connector plugged into the power seat adjuster mo-
tors end-bell. (4) Check for ground at pin 4 of the natural 5-way
connector plugged into the power seat adjuster mo-
tors end-bell. If the power seat adjuster still has no
movement in the recall mode, then continue this pro-
cedure. (5) Disconnect the natural 5-way connector from
the power seat adjuster motors end-bell. (6) Check with an ohmmeter for a resistance read-
ing that may be from 2600 to 4000 ohms between
pins 4 and 5 of the motors end-bell connector. If
there is an open circuit reading or the reading ob-
tained falls outside this range, then replace the seat
motor package assembly. After replacement of the
seat motor package, reconnect all wiring connectors
and reinstall seat assembly in vehicle. Operate the
switches manually to cause maximum seat move-
ment in all directions. Perform the memory seat di-
agnostic self check so the control module will learn
the new soft limits of the assembly.
CONDITION: NO SEAT TRACK FORWARD OR REARWARD MOVEMENT IN THE RECALLMODE, SEAT TRACK WILL MOVE FORWARDOR REARWARD BY MANUAL SWITCHACTUATION WITHOUT STALL DETECTION.
PROCEDURE
(1) Check for a voltage at pin 12 of the control
module 21-way connector. Less than 5 volts for the
seat track fully forward and more than 0 volts when
fully rearward. This voltage should vary correspond-
ing to the position. (2) Check for a voltage at pin 1 of the natural
5-way connector, Same as in step (1) above. The
ground lead connected to pin 4 of the 5-way connec-
tor. If the voltage reading is at 0 volts, disconnect
the 5-way natural connector and check for a short to
ground in the harness. If no short is found, reconnect
the connector and continue the procedure. (3) Check for the voltage to vary as noted above, if
it does not vary as the seat track is moved forward
and rearward, the sensing potentiometer is defective.
Replace the seat motor package assembly. After re-
placement of the seat motor package, reconnect all
wiring connectors and reinstall seat assembly in ve-
hicle. Operate the switches manually to cause maxi-
mum seat movement in all directions. Perform the
memory seat diagnostic self check so the control
module will learn the new soft limits of the assem-
bly.
Ä POWER SEATS 8R - 13