seat memory CHEVROLET DYNASTY 1993 Service Manual

(11) Remove all special tools previously installed,
from the ABS hydraulic assembly. (12) Install accumulator port plug into hydraulic
assembly. Torque accumulator port plug to 12 N Im(9
ft. lbs.). (13) Install high pressure brake hose from the
pump motor assembly into hydraulic fitting on ABS
hydraulic assembly. Torque high pressure brake hose
tube nut to 16 N Im (145 in. lbs.).
(14) Turn ignition switch to the run position to en-
ergize the pump/motor assembly and pressurize hy-
draulic system. Check for leakage at the hydraulic
assembly to hydraulic bladder accumulator fitting. (15) Again de-pressurize accumulator by pumping
brake pedal a minimum of 40 times. Use procedure
described in De-Pressurizing Hydraulic Accumulator
in this section of the service manual. (16) Then check the brake fluid level in the hy-
draulic assembly reservoir. If brake fluid level is low,
fill reservoir to proper level with Mopar tbrake fluid
or equivalent conforming to DOT 3 requirements.
INTERMITTENT FAULTS
As with almost any electronic system, intermittent
faults in the ABS system may be difficult to accu-
rately diagnose. Most intermittent faults are caused by faulty elec-
trical connections or wiring. When an intermittent
fault is encountered, check suspect circuits for: (1) Poor mating of electrical connector halves, or
electrical terminals not fully seated in the connector
body. (2) Improperly formed or damaged electrical termi-
nals. All connector terminals in a suspect circuit
should be carefully reformed to increase contact ten-
sion. (3) Poor terminal to wire connection. This requires
removing the terminal from the connector body and
inspecting for proper terminal to wire connection. If a visual check does not find the cause of the
problem, operate the vehicle in an attempt to dupli-
cate the condition and record the Fault Code. Most failures of the ABS system will disable the
Anti-Lock function for the entire ignition cycle even
if the fault clears before ignition key-off. There are
some failure conditions however, which will allow
ABS operation to resume during the ignition cycle in
which a failure occurred. If the failure conditions are
no longer present. The following conditions may result in intermittent
illumination of the Red Brake Warning Lamp and/or
Amber Anti-Lock Warning Lamp. All other failures
will cause the lamp(s) to remain on until the ignition
switch is turned off. Circuits and or components in-
volving these inputs to the (CAB) should be investi-
gated if a complaint of intermittent warning system
operation is encountered. ²
Low system voltage. If low system voltage is de-
tected by the (CAB), the (CAB) will turn on the Am-
ber Anti-Lock Warning Lamp until normal system
voltage is achieved. Once normal voltage is seen at
the (CAB), normal operation resumes.
² Low Brake Fluid. A low brake fluid condition will
cause the Red Brake Warning Lamp to illuminate.
When the fluid sensor again indicates an acceptable
fluid level, the Red Brake Warning Lamp will go out.
This condition may exist during hard cornering or
while the vehicle is on a grade. If the vehicle is in
motion above 3 M.P.H. the Amber Anti-Lock Warn-
ing Lamp will also be turned on.
² Low Accumulator Pressure. Low Accumulator
Pressure will cause both the Red Brake Warning and
Amber Anti-Lock Warning Lamps to illuminate.
Once normal operating pressure is achieved, the
lamps will extinguish and the system will return to
normal operation. Additionally, any condition that results in an inter-
ruption of power to the (CAB) or hydraulic assembly.
May cause the Red Brake Warning and Amber Anti-
Lock Warning Lamps to illuminate intermittently. All the conditions (or faults) mentioned above, can
store a fault code in the (CAB) module.
ABS BRAKE SYSTEM DIAGNOSTIC FEATURES
SYSTEM SELF DIAGNOSIS
The ABS system is equipped with a diagnostic ca-
pability that may be used to assist in isolation of
ABS faults. The features of the diagnostics system
are described below.
CONTROLLER ANTI-LOCK BRAKE (CAB)
Fault codes are kept in a Non-Volatile memory un-
til either erased by the technician using the DRB II
or erased automatically after 50 ignition cycles (key
ON-OFF cycles). The only fault that will not be
erased after 50 (KEY CYCLES) is the (CAB) fault.
The (CAB) fault can only be erased by using the
DRB II diagnostic tester. More than one fault can be
stored at a time. The number of key cycles since the
most recent fault was stored is also displayed. Most
functions of the (CAB) and (ABS) system can be ac-
cessed by the technician for testing and diagnostic
purposes by using the DRB II Diagnostic Tester.
START-UP CYCLE
The START-UP CYCLE takes place immediately
after the ignition switch is turned on. It is an elec-
trical check of basic electrical functions such as the
System Relay and Anti-Lock Warning Lamp Relay.
During this check, the Amber Anti-Lock Warning
Lamp is turned on, then turned off at the end of the
test. The test takes approximatel y1-2seconds to
complete.
5 - 92 ANTI-LOCK 10 BRAKE SYSTEM Ä

MECHANICAL DIAGNOSTICS AND SERVICE
PROCEDURES
SPECIAL SERVICE TOOL
Some diagnostic procedures in this section require
the use of the DRB II diagnostics tester. The proper
application and procedures for the use of this tool are
described below.
DRB II DIAGNOSTIC TESTER Some of the diagnostic procedures that are ex-
plained in this section require the use of the DRB II
Diagnostics Tester to insure that proper diagnostics
are performed. Refer to those sections for proper test-
ing procedures and the DRB II operators manual for
its proper operational information.
INTERMITTENT FAULTS
As with virtually any electronic system, intermit-
tent faults in the ABS system may be difficult to ac-
curately diagnose. Most intermittent faults are caused by faulty elec-
trical connections or wiring. When an intermittent
fault is encountered, check suspect circuits for: (1) Poor mating of connector halves or terminals
not fully seated in the connector body. (2) Improperly formed or damaged terminals. All
connector terminals in a suspect circuit should be
carefully reformed to increase contact tension. (3) Poor terminal to wire connection. This requires
removing the terminal from the connector body to in-
spect. (4) Pin presence in the connector assembly
If a visual check does not find the cause of the
problem, operate the car in an attempt to duplicate
the condition and record the Fault code. Most failures of the ABS system will disable Anti-
Lock function for the entire ignition cycle even if the
fault clears before key-off. There are some failure
conditions, however, which will allow ABS operation
to resume during the ignition cycle in which a fail-
ure occurred. If the failure conditions are no longer
present. The following conditions may result in inter-
mittent illumination of the Amber Anti-Lock Warn-
ing Lamp. All other failures will cause the lamp to
remain on until the ignition switch is turned off. Cir-
cuits involving these inputs to the (CAB) should be
investigated if a complaint of intermittent warning
system operation is encountered. (1) Low system voltage. If Low System Voltage is
detected by the (CAB), the (CAB) will turn on the
Amber Anti-Lock Warning Lamp until normal sys-
tem voltage is achieved. Once normal voltage is seen
at the (CAB), normal operation resumes. (2) Anti-Lock relay. If the relay fails to make the
ground circuit connection or is an intermittent
ground. The (CAB) will turn on the Amber Anti-Lock
Warning Light. (3) Excess decay, an extended pressure decay pe-
riod, will turn on the Amber Anti-Lock Warning
Light until the vehicle comes to a complete stop. Additionally, any condition which results in inter-
ruption of electrical current to the (CAB) or modula-
tor assembly. May cause the Amber Anti-Lock
Warning Lamp to turn on intermittently.
ABS BRAKE SYSTEM DIAGNOSTIC FEATURES
ABS SYSTEM SELF DIAGNOSIS
The ABS system is equipped with a self diagnostic
capability which may be used to assist in isolation of
ABS faults. The features of the self diagnostics sys-
tem are described below.
START-UP CYCLE
The self diagnostic ABS start up cycle begins when
the ignition switch is turned to the on position. An
electrical check is completed on the ABS components.
Such as Wheel Speed Sensor Continuity and System
and other Relay continuity. During this check the
Amber Anti-Lock Light is turned on for approxi-
mately 1- 2 seconds. Further Functional testing is accomplished once
the vehicle is set in motion.
² The solenoid valves and the pump/motor are acti-
vated briefly to verify function.
² The voltage output from the wheel speed sensors is
verified to be within the correct operating range. If the vehicle is not set in motion within 3 minutes
from the time the ignition switch is set in the on po-
sition. The solenoid test is bypassed but the pump/
motor is activated briefly to verify that it is
operating correctly.
CONTROLLER ANTI-LOCK BRAKE (CAB)
Fault codes are kept in a Non-Volatile memory un-
til either erased by the technician using the DRB II
or erased automatically after 50 ignition cycles (key
ON-OFF cycles). The only fault that will not be
erased after 50 (KEY CYCLES) is the (CAB) fault. A
(CAB) fault can only be erased by the technician us-
ing the DRB II diagnostic tester. More than one fault
can be stored at a time. The number of key cycles
since the most recent fault was stored is also dis-
played. Most functions of the (CAB) and ABS system
can be accessed by the technician for testing and di-
agnostic purposes by using the DRB II.
LATCHING VERSUS NON-LATCHING ABS FAULTS
Some faults detected by the (CAB) are latching; the
fault is latched and (ABS) is disabled until the igni-
tion switch is reset. Thus ABS is disabled even if the
original fault has disappeared. Other faults are non-
latching; any warning lights that are turned on, are
only turned on as long as the fault condition exists.
Ä ANTI-LOCK 6 BRAKE SYSTEM 5 - 125

manual. May result in contact with moving parts or
over extension of cables, resulting in component fail-
ure and an open circuit.
MECHANICAL DIAGNOSTICS AND SERVICE
PROCEDURES
SPECIAL SERVICE TOOL
Some diagnostic procedures in this section require
the use of the DRB diagnostics tester. The proper ap-
plication and procedures for the use of this tool are
described below.
DRB DIAGNOSTIC TESTER
Some of the diagnostic procedures that are ex-
plained in this section require the use of the DRB Di-
agnostics Tester to insure that proper diagnostics are
performed. Refer to those sections for proper testing
procedures and the DRB operators manual for its
proper operational information.
INTERMITTENT FAULTS
As with virtually any electronic system, intermit-
tent faults in the ABS system may be difficult to ac-
curately diagnose. Most intermittent faults are caused by faulty elec-
trical connections or wiring. When an intermittent
fault is encountered, check suspect circuits for: (1) Poor mating of wiring harness connector halves
or terminals not fully seated in the connector body. (2) Improperly formed or damaged terminals. All
connector terminals in a suspect circuit should be
checked and carefully reformed to increase contact
tension with its mating terminal. (3) Poor terminal to wire connection. This requires
removing the terminal from the connector body to in-
spect. (4) Pin presence in the connector assembly
(5) Connector push-in, spread, and corrosion.
If a visual check does not find the cause of the
problem, operate the car in an attempt to duplicate
the condition and record the set Fault code. Most failures of the ABS system will disable the
Antilock function for the entire ignition cycle even if
the fault clears before key-off. There are some failure
conditions, however, which will allow ABS operation
to resume during the ignition cycle in which it oc-
curred, if the failure condition is no longer present.
The following conditions may result in intermittent
illumination of the Amber Antilock Warning Lamp.
All other failures will cause the lamp to remain on
until the ignition switch is turned off. Circuits in-
volving these inputs to the CAB should be investi-
gated if a complaint of intermittent warning system
operation is encountered. (1) Low system voltage: If Low System Voltage is
detected by the CAB, the CAB will turn on the Am-
ber Antilock Warning Lamp until normal system voltage is achieved. Once normal voltage is seen at
the CAB, normal operation resumes.
(2) Antilock system and pump/motor relay. If the
relays fail to make the ground circuit connection or
has an intermittent ground. The CAB will turn on
the Amber Antilock Warning Light. (3) Excess decay, an extended pressure decay pe-
riod, will turn on the Amber Antilock Warning Light
until the vehicle comes to a complete stop. Additionally, any condition which results in inter-
ruption of electrical current to the CAB or modulator
assembly, may cause the Amber Antilock Warning
Lamp to turn on intermittently.
ABS BRAKE SYSTEM DIAGNOSTIC FEATURES
ABS SYSTEM SELF DIAGNOSIS
The ABS system is equipped with a self diagnostic
capability which may be used to assist in isolation of
ABS faults. The features of the self diagnostics sys-
tem are described below.
START-UP CYCLE
The self diagnostic ABS start up cycle begins when
the ignition switch is turned to the on position. An
electrical check is completed on the ABS components.
Such as Wheel Speed Sensor Continuity and System
and other Relay continuity. During this check the
Amber Antilock Light is turned on for approximately
1- 2 seconds. Further Functional testing is accomplished once
the vehicle is set in motion, known as drive-off.
² The solenoid valves and the pump/motor are acti-
vated briefly to verify function.
² The voltage output from the wheel speed sensors is
verified to be within the correct operating range. If the vehicle is not set in motion within 3 minutes
from the time the ignition switch is set in the on po-
sition. The solenoid test is bypassed but the pump/
motor is activated briefly to verify that it is
operating correctly.
CONTROLLER ANTILOCK BRAKE CAB
Fault codes are kept in a Non-Volatile memory un-
til either erased by the technician using the DRB or
erased automatically after 50 ignition cycles (key
ON-OFF cycles). The only fault that will not be
erased after 50 (KEY CYCLES) is the CAB fault. A
CAB fault can only be erased by the technician using
the DRB diagnostic tester. More than one fault can
be stored at a time. The number of key cycles since
the most recent fault was stored is also displayed.
Most functions of the CAB and ABS system can be
accessed by the technician for testing and diagnostic
purposes by using the DRB.
5 - 24 ANTILOCK 4 BRAKE SYSTEM Ä

AC AND AY BODIES INDEX
page page
Electronic Cluster ........................ 34
Gauges ................................ 28
General Information ....................... 23
Interior Lamp Replacement ................. 41 Mechanical Cluster and Gauge Service
........ 24
Mechanical/Electronic Cluster Removal ........ 25
Switch and Panel Component Service ......... 37
GENERAL INFORMATION
MECHANICAL CLUSTER
The mechanical cluster includes a fuel, oil pres-
sure, coolant temperature, and voltmeter gauges. All
incorporate magnetic type gauges. When the ignition
switch is in the OFF position, the gauges will show a
reading; however, the readings are only accurate
when the ignition switch is in the ON position. The mechanical cluster also includes an electric
speedometer, driven by pulses from the vehicle speed
sensor (Fig. 1).
ELECTRONIC CLUSTER
The electronic cluster is easily distinguished from
the mechanical cluster by its digital and linear dis-
play. The electronic cluster includes:
² Oil pressure gauge
² Coolant temperature gauge
² Voltmeter
² Fuel gauge
The electronic cluster receives virtually all of its
information to display from the body controller and
powertrain control module via the Chrysler Collision
Detection (CCD) Serial Data Bus. The odometer
memory is no longer retained in the cluster. This is
now retained in the body controller (Fig. 2).
ELECTRONIC CLUSTER DIMMING
The electronic cluster display is dimmed from day-
time to night time intensity when the headlamp
switch is turned on. This intensity can be controlled
using the headlamp switch rheostat. An additional detent on the headlamp switch rheo-
stat will allow daytime intensity while driving with
headlamps on during the daytime.
WARNING LAMPS
The mechanical instrument cluster will have warn-
ing lamps for six systems. These include brake sys-
tem, air bag, seat belt, low fuel, anti-lock for optional
anti-lock brake system, and malfunction indicator
(check engine) lamp. The cluster also includes check
gages indicator which will illuminate in a warning
situation. This will notify driver to check for a prob-
lem in coolant temperature, oil pressure, or electrical
systems. The electronic cluster will have warning indicator
lamps for eight different systems. These include:
² Air Bag
² Low washer fluid
² Door/deck lid ajar
² Malfunction Indicator (Check engine) Lamp
² Brake system
² Seat belt
² Anti-lock (ABS) for optional anti-lock brake sys-
tem
² Check gages, monitors engine coolant, oil pressure
and electrical charging system failures. In addition, ISO symbol will flash to notify the
driver in event of:
² Low fuel
² High temperature
² Low oil pressure
² Charging system failure
Fig. 1 Mechanical Cluster
Fig. 2 Electronic Cluster
Ä INSTRUMENT PANEL AND GAUGES 8E - 23

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

jumper wire between pin 7 and 2.If motor does not op-
erate, reverse the jumpers, pin 5 to pin 2 and pin 7 to 6.
If motor still does not operate check 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.
AG & AJ BODIES
(1) Remove switch from mounting position and dis-
connect from harness. (2) To check the front motor, connect a jumper
wire between cavity number 2 and cavity number 9
(Fig. 2). Connect a second jumper wire between cav-
ity number 6 and cavity number 5. If the motor does
not operate, reverse the jumpers, 2 to 5 and 6 to 9. If
motor still does not operate check wiring between
switch connector and motor assembly. If wiring
checks good replace motor assembly. (3) To check the center motor, connect a jumper
wire between cavity number 2 and cavity number 8.
Connect a second jumper wire between cavity 6 and
cavity number 7. If the motor does not operate, re-
verse the jumpers, 2 to 7 and 6 to 8. If motor still
does not operate check wiring between switch con-
nector and motor assembly. If wiring checks good re-
place motor assembly. (4) To check the rear motor, connect a jumper be-
tween cavity number 2 and cavity number 10. Con-
nect a second jumper wire between cavity number 6
and cavity number 3. If the motor does not operate,
reverse the jumpers, 2 to 3 and 6 to 10. If motor still
does not operate, check wiring between switch con-
nector and motor assembly. If wiring checks good re-
place motor assembly. (5) To check the seat back recliner motor if
equipped, connect a jumper wire be tween cavity
number 2 and cavity number 1. Connect a second
jumper wire between cavity number 6 and cavity
number 11. If the motor does not operate, reverse the jumpers (2 to 11 and 6 to 1). If motor still does not
operate check wiring be tween switch connector and
motor assembly. If wiring checks good replace motor
assembly.
(6) If all motors and the seat operate properly, per-
form Switch Test.
AC AND AY BODIES
The following tests do not apply to left seat on ve-
hicles equipped with memory mirrors/seats. Refer to
test procedures for power memory mirrors/seats in
this section. (1) Remove switch from mounting position and dis-
connect from harness. (2) To check the front motor, connect a jumper
wire between cavity number 3 and cavity number 8
(Fig. 3 and 4). Connect a second jumper wire between
cavity number 6 and cavity number 7. If the motor
does not operate, reverse the jumpers, 3 to 7 and 6 to
8. If the motor still does not operate check the wiring
between switch connector and motor assembly. If
wiring checks good replace motor assembly. (3) To check the center motor, connect a jumper
wire between cavity number 3 and cavity number 5.
Connect a second jumper wire between cavity num-
ber 6 and cavity number 2. If the motor does not op-
erate, reverse the jumpers, 3 to 2 and 6 to 5. If the
motor still does not operate check the wiring between
Fig. 1 Power Seat Switch ConnectorÐAA Body
Fig. 2 Power Seat Switch ConnectorÐAG & AJ Bodies
8R - 2 POWER SEATS Ä

wing. Refer to Owner Manual supplied with vehicle
for complete instructions for seat operation.
SWITCH TEST
For switch testing, remove switch from its mount-
ing location. Using an ohmmeter, refer to Figures 13
and 14 to determine if continuity is correct. If these
results are not obtained, replace the switch.
SWITCH REPLACEMENT REMOVAL
(1) Remove left cushion side shield.
(2) Disconnect wiring from switch.
(3) Depress bezel retainers and push switch from
bezel. (4) For installation, reverse above procedure.
POWER MEMORY SEAT, RECLINER AND
MIRRORS
AC & AY Body vehicles have, as an option, a spe-
cial 2 position memory power seat, recliner and
memory power outside rear view mirror system.
Each of the components can be moved to a desired
position by operating switches (Fig. 15). The seat and
recliner use potentiometers as position sensors and
the mirrors use rheostats to send their positioning
information back to the control module in the driv-
er's seat. After the desired seat and mirror position is
set. The seat, recliner, and mirror position can be
memorized at any time by pressing and release the
Set button. Followed by pressing the Position 1 or 2
button, for the specific position desired. DO NOT
press any other seat related switch for at least 5 sec-
onds. However, for the driver to recall a position, the
vehicle must not be moving and the seat belt must
NOT be buckled. Refer to the Owners Manual sup-
plied with the vehicle for complete instructions on
system operation.
Fig. 7 Switch ContinuityÐAG & AJ Bodies (8-Way)
Fig. 8 Seat AdjusterÐAC and AJ Bodies
Ä POWER SEATS 8R - 5

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

but less than 10 seconds, and then release. The seat
will move, after 3 seconds, to a full down and rear-
ward position. This is the seat check mode. The control module
will now move the motors to a stall in forward, rear-
ward, front up, front down, rear up, rear down, re-
cliner forward, and recliner rear ward positions. If a
problem exists, the control module will not move that
part of the seat. After all motors have been run to
stall, the system will pause for 3 seconds, then re-
turn to the mid-travel position. The control module will now move the seat through
its positions for two seconds run time. If a problem has been found, the control module
will go into a loop and just move the problem part of
the system. To exit the loop, press the Set or Position
1 or 2 buttons or repair the fault; i.e.: repair a ter-
minal push out, etc. When the seat movements are complete, the sys-
tem will return to its normal operating mode unless
memory Position 1 and 2 buttons are held for at least
five seconds, but less than ten seconds and then re-
leased. The seat will return to its mid-travel position
and the mirrors will move full downward and to the
left. This is the mirror check mode. The control mod-
ule will then move the right mirror fully horizontal
outboard, and horizontal inboard. This is followed by
the left mirror fully horizontal inboard, horizontal
out board, vertical up, and vertical down. Each motor
will be driven until the associated mirror plane face
has been stalled for up to 1-1/2 seconds at each end
of travel. If the control module encounters a problem
with any position sensing rheostat that is connected
to each motor, that particular motor will not be ac-
tuated. After an other three second pause, the control
module will again try running the mirror motors in
the directions given above plus the right mirror ver-
tical up and vertical down. Any motor that has no
problem will run for two seconds in each of the given
directions. If a problem is found, the control module will go
into a loop and move only the problem part of the
system. To exit the loop, repair the fault, or press the
Set, Position 1 or 2 buttons. The control module will
then finish the motor actuation that are shown
Fig. 13 Seat Wing Switch Continuity
Fig. 14 Lumbar Switch Continuity
Fig. 15 Memory Seat Switch
8R - 8 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