(7) Install the right front lower splash shield.
(8) Lower vehicle.
(9) Connect battery negative cable.
VOLTAGE REGULATOR
DESCRIPTION
The Electronic Voltage Regulator (EVR) is not a
separate component. It is actually a voltage regulat-ing circuit located within the Powertrain Control
Module (PCM). The EVR is not serviced separately. If
replacement is necessary, the PCM must be replaced.
OPERATION
The amount of DC current produced by the gener-
ator is controlled by EVR circuitry contained within
the PCM. This circuitry is connected in series with
the generators second rotor field terminal and its
ground.
Voltage is regulated within the PCM on the NGC
vehicles, to control the strength of the rotor magnetic
field. The EVR circuitry monitors system line voltage
at the PDC and calculated battery temperature or
inlet air temperature sensor (refer to Inlet Air Tem-
perature Sensor, if equipped, for more information ).
It then determines a target charging voltage. If
sensed battery voltage is lower than the target volt-
age, the PCM feeds the field winding until sensed
battery voltage is at the target voltage. A circuit in
the PCM cycles the feed side of the generator field at
250 times per second (250Hz), but has the capability
to feed the field control wire 100% of the time (full
field) to achieve the target voltage. If the charging
rate cannot be monitored (limp-in), a duty cycle of
20% is used by the PCM in order to have some gen-
erator output. Also refer to Charging System Opera-
tion for additional information.
Fig. 15 DECOUPLER INSTALLATION (Litens)
8F - 30 CHARGINGRS
GENERATOR DECOUPLER PULLEY (Continued)
CONDITION POSSIBLE CAUSE CORRECTION
2. STARTING CIRCUIT
WIRING FAULTY.2. REFER TO THE FEED CIRCUIT RESISTANCE TEST AND
THE FEED CIRCUIT TEST IN THIS SECTION. REPAIR AS
NECESSARY.
3. STARTER ASSEMBLY
FAULTY.3. IF ALL OTHER STARTING SYSTEM COMPONENTS AND
CIRCUITS CHECK OK, REPLACE STARTER ASSEMBLY.
4. ENGINE SEIZED. 4. REFER TO THE ENGINE SECTION, FOR DIAGNOSTIC AND
SERVICE PROCEDURES.
5. LOOSE
CONNECTION AT
BATTERY, PDC,
STARTER, OR ENGINE
GROUND.5. INSPECT FOR LOOSE CONNECTIONS.
6. FAULTY TEETH ON
RING GEAR.6. ROTATE FLYWHEEL 360É, AND INSPECT TEETH AND RING
GEAR REPLACED IF DAMAGED.
STARTER
ENGAGES,
SPINS OUT
BEFORE
ENGINE
STARTS.1. BROKEN TEETH ON
STARTER RING GEAR.1. REMOVE STARTER. INSPECT RING GEAR AND REPLACE
IF NECESSARY.
2. STARTER ASSEMBLY
FAULTY.2. IF ALL OTHER STARTING SYSTEM COMPONENTS AND
CIRCUITS CHECK OK, REPLACE STARTER ASSEMBLY.
STARTER DOES
NOT
DISENGAGE.1. STARTER
IMPROPERLY
INSTALLED.1. INSTALL STARTER. TIGHTEN STARTER MOUNTING
HARDWARE TO CORRECT TORQUE SPECIFICATIONS.
2. STARTER RELAY
FAULTY.2. REFER TO RELAY TEST, IN THIS SECTION. REPLACE
RELAY, IF NECESSARY.
3. IGNITION SWITCH
FAULTY.3. REFER TO IGNITION SWITCH TEST, IN THE STEERING
SECTION. REPLACE SWITCH, IF NECESSARY.
4. STARTER ASSEMBLY
FAULTY.4. IF ALL OTHER STARTING SYSTEM COMPONENTS AND
CIRCUITS CHECK OK, REPLACE STARTER ASSEMBLY.
5. FAULTY TEETH ON
RING GEAR.5. ROTATE FLYWHEEL 360É, AND INSPECT TEETH AND RING
GEAR REPLACED IF DAMAGED.
DIAGNOSIS AND TESTING - CONTROL
CIRCUIT TEST
The starter control circuit has:
²Starter motor with integral solenoid
²Starter relay
²Transmission range sensor, or Park/Neutral
Position switch with automatic transmissions
²Ignition switch
²Battery
²All related wiring and connections
²Powertrain Control Module (PCM)
CAUTION: Before performing any starter tests, the
ignition and fuel systems must be disabled.²To disable ignition and fuel systems, disconnect
the Automatic Shutdown Relay (ASD). The ASD relay
is located in the Power Distribution Center (PDC).
Refer to the PDC cover for the proper relay location.
STARTER SOLENOID
WARNING: CHECK TO ENSURE THAT THE TRANS-
MISSION IS IN THE PARK POSITION WITH THE
PARKING BRAKE APPLIED. THIS MAY RESULT IN
PERSONAL INJURY OR DEATH.
(1) Verify battery condition. Battery must be in
good condition with a full charge before performing
any starter tests. Refer to Battery Tests.
RSSTARTING8F-33
STARTING (Continued)
HEATED SYSTEMS
TABLE OF CONTENTS
page page
HEATED GLASS........................... 1
HEATED MIRRORS......................... 6HEATED SEAT SYSTEM..................... 7
HEATED GLASS
TABLE OF CONTENTS
page page
HEATED GLASS
DESCRIPTION..........................1
OPERATION............................2
DIAGNOSIS AND TESTING
ELECTRIC BACKLIGHT (EBL) SYSTEM.....2
REAR WINDOW DEFOGGER RELAY
DESCRIPTION..........................3
OPERATION............................3REMOVAL.............................4
INSTALLATION..........................4
REAR WINDOW DEFOGGER SWITCH
DESCRIPTION..........................4
OPERATION............................4
REAR WINDOW DEFOGGER GRID
STANDARD PROCEDURE
GRID REPAIR PROCEDURE..............5
HEATED GLASS
DESCRIPTION
CAUTION: Grid lines can be damaged or scraped
off with sharp instruments. Care should be taken in
cleaning glass or removing foreign materials,
decals or stickers. Normal glass cleaning solvents
or hot water used with rags or toweling is recom-
mended.
The rear window defogger system, also known as
electrical backlight (EBL), consists of two vertical bus
bars linked by a series of grid lines fired onto the
inside surface of the rear window (Fig. 1).
The EBL system is turned ON or OFF by a control
switch located on the A/C-heater control at the center
of the instrument panel and by a rear window defog-
ger relay timing circuit integral to the integrated
power module (IPM) (Refer to 8 - ELECTRICAL/
HEATED GLASS/REAR WINDOW DEFOGGER
SWITCH - DESCRIPTION).
Circuit protection is provided by a 40 amp fuse
located in the IPM.
Fig. 1 Rear Window Defogger - Typical
1 - REAR DEFOGGER GRID
2 - REAR WINDOW
RSHEATED SYSTEMS8G-1
OPERATION
When the rear window defogger button is
depressed to the On position, current is directed to
the rear defogger grid lines and the heated power
mirrors (if equipped). The heated grid lines heat the
glass to help clear the rear window and side mirror
surfaces of fog or frost.
The electric backlight (EBL) system is controlled
by a momentary switch located in the A/C-heater
control on the instrument panel. A yellow indicator in
the switch will illuminate to indicate when the sys-
tem is turned on. The integrated power module (IPM)
contains the EBL system control circuitry.
NOTE: The rear window defogger turns off automat-
ically after approximately 10 minutes of initial oper-
ation. Each following activation cycle of the
defogger system will last approximately five min-
utes.
The EBL system will be automatically turned off
after a programmed time interval of about ten min-
utes. After the initial time interval has expired, if the
defogger switch is turned on again during the same
ignition cycle, the defogger system will automatically
turn off after about five minutes.
The EBL system will automatically shut off if the
ignition switch is turned to the Off position, or it can
be turned off manually by depressing the defogger
switch a second time.
DIAGNOSIS AND TESTING
ELECTRIC BACKLIGHT (EBL) SYSTEM
NOTE: Illumination of the defogger switch indicator
lamp means that there is electrical current available
at the output of the rear window defogger logic cir-
cuitry, but does not confirm that the electrical cur-
rent is reaching the rear glass heating grid lines.
NOTE: For circuit descriptions and diagrams of the
rear window defogger system, refer to 8W - WIRING
DIAGRAM INFORMATION.
Operation of the electrical backlight (EBL) system
can be confirmed by the following:(1) Turn the ignition switch to the On position. Set
the defogger switch in the On position. The rear win-
dow defogger operation can be checked by feeling the
rear window glass. A distinct difference in tempera-
ture between the grid lines and the adjacent clear
glass can be detected within three to four minutes of
operation.
(2) If a temperature difference is not detected, use
a 12-volt DC voltmeter and contact the rear glass
heating grid terminal B with the negative lead, and
terminal A with the positive lead (Fig. 2). The volt-
meter should read battery voltage. If the voltmeter
does not read battery voltage, check the following:
²Confirm that the ignition switch is in the On
position.
²Make sure that the rear glass heating grid feed
wire and ground wire are connected to the terminals.
Confirm that the ground wire has continuity to
ground.
²Check that fuse 13 (40 amp) in the integrated
power module (IPM) is OK. The fuse must be tight in
it's receptacle and all electrical connections must be
secure.
(3) When the above steps have been completed and
the rear glass heating grid is still inoperative, one or
more of the following is faulty. It may be necessary to
connect a DRBIIItscan tool to perform further diag-
nostics. Refer to Body Diagnostic Procedures.
²Rear window defogger switch in the A/C-heater
control.
²J1850 bus communication between the A/C-
heater control and the front control module (FCM).
²Rear window defogger (EBL) relay in the IPM.
²Rear window defogger (EBL) relay control circu-
ity in the IPM.
²Check for a loose wire connector or a wire
pushed out of a connector.
²Rear window grid lines (all grid lines would
have to be broken, or the power feed or ground wire
not connected, for the entire heating grid to be inop-
erative).
(4) If the system operation has been verified but
defogger switch LED indicator does not illuminate,
replace the A/C-heater control.
8G - 2 HEATED GLASSRS
HEATED GLASS (Continued)
(5) If broken defogger grid lines are suspected, use
a 12-volt DC voltmeter and contact terminal B with
the negative lead and each rear glass heating grid
line at it's mid-point with the positive lead. The volt-
meter should read approximately 6 volts at each grid
line mid-point C. If the voltmeter does not read
approximately 6 volts, repair the open grid line(s)
(Refer to 8 - ELECTRICAL/HEATED GLASS/REAR
WINDOW DEFOGGER GRID - STANDARD PROCE-
DURE).
REAR WINDOW DEFOGGER
RELAY
DESCRIPTION
The rear window defogger (EBL) relay (Fig. 3) is a
International Standards Organization (ISO)-type
relay. Relays conforming to the ISO specifications
have common physical dimensions, current capaci-
ties, terminal patterns, and terminal functions. The
rear window defogger relay is a electromechanical
device that switches battery current through a fuse
in the integrated power module (IPM) to the rear
window defogger grid and switches battery current
through a positive thermal coefficient (PTC) in the
IPM to the outside mirror heating grids. The relay isenergized when the relay coil is provided a ground
path by the rear window defogger relay control in the
front control module (FCM).
The rear window defogger (EBL) relay is located in
the IPM in the engine compartment. See the fuse
and relay layout map on the inner surface of the
cover of the IPM for rear window defogger relay iden-
tification and location.
The rear window defogger (EBL) relay cannot be
adjusted or repaired and, if damaged or faulty, it
must be replaced.
OPERATION
The ISO-standard rear window defogger (EBL)
relay consists of an electromagnetic coil, a resistor or
diode, and three (two fixed and one movable) electri-
cal contacts. The movable (common feed) relay con-
tact is held against one of the fixed contacts
(normally closed) by spring pressure. When the elec-
tromagnetic coil is energized, it draws the movable
contact away from the normally closed fixed contact,
and holds it against the other (normally open) fixed
contact.
When the electromagnetic coil is de-energized,
spring pressure returns the movable contact to the
normally closed position. The resistor is connected in
parallel with the electromagnetic coil in the relay,
and helps to dissipate voltage spikes that are pro-
duced when the coil is de-energized.
Refer to the appropriate wiring information for
diagnosis and testing of the EBL relay and for com-
plete EBL system wiring diagrams.
Fig. 2 Grid Line Test
1 - VOLTMETER
2 - VOLTAGE FEED (A)
3 - FEED WIRE
4 - MID-POINT (C)
5 - HEATED WINDOW GRID
6 - GROUND WIRE
7 - GROUND (B)Fig. 3 Rear Window Defogger (EBL) Relay
RSHEATED GLASS8G-3
HEATED GLASS (Continued)
REMOVAL
(1) Disconnect and isolate the negative battery
cable.
(2) Remove the cover from the integrated power
module (IPM) (Fig. 4).
NOTE: Refer to the fuse and relay layout map on
the inner surface of the cover of the IPM for rear
window defogger (EBL) relay identification and
location.
(3) Remove the EBL relay from the IPM.
INSTALLATION
NOTE: Refer to the fuse and relay map on the inner
surface of the cover of the integrated power module
(IPM) for rear window defogger (EBL) relay identifi-
cation and location.
(1) Position the EBL relay into the proper recepta-
cle in the IPM.
(2) Align the EBL relay terminals with the termi-
nal cavities in the IPM receptacle.
(3) Push down firmly on the EBL relay until the
terminals are fully seated in the terminal cavities.
(4) Install the cover onto the IPM.
(5) Reconnect the negative battery cable.
REAR WINDOW DEFOGGER
SWITCH
DESCRIPTION
The switch for the EBL system is integrated into
the A/C-heater control located in the center of the
instrument panel (Fig. 5).
When the rear window defogger switch is turned to
the ON position, current is directed to the rear defog-
ger grid lines and the heated power mirrors (if
equipped). The heated grid lines heat the glass to
help clear the surface of fog or frost.
OPERATION
Depressing the rear window defogger switch ener-
gizes the A/C-heater control module which then
requests the front control module (FCM) to activate
the rear window defogger (EBL) relay via the com-
munication bus. The EBL relay controls the current
to flow to the grids of the rear window defogger and
the heated power side view mirrors. The EBL relay
will be on for approximately 10 minutes or until the
control switch or ignition is turned off. An amber
indicator lamp in the defogger switch illuminates to
indicate when the EBL system is On.
The rear window defogger switch and indicator
lamp cannot be repaired and, if faulty or damaged,
the entire A/C-heater control must be replaced.
Fig. 4 Rear Window Defogger (EBL) Relay
1 - INTEGRATED POWER MODULE (IPM)
2 - REAR WINDOW DEFOGGER (EBL) RELAY
3 - FRONT CONTROL MODULE (FCM)
Fig. 5 A/C-Heater Control - Typical
1 - TRIM BEZEL
2 - INFRARED TEMPERATURE SENSOR
3 - A/C REQUEST SWITCH
4 - EBL/HEATED MIRROR SWITCH
5 - FRONT WINDOW DEFROSTER SELECTOR
8G - 4 HEATED GLASSRS
REAR WINDOW DEFOGGER RELAY (Continued)
HEATED SEAT SYSTEM
TABLE OF CONTENTS
page page
HEATED SEAT SYSTEM
DESCRIPTION..........................7
OPERATION............................8
DIAGNOSIS AND TESTING
HEATED SEAT SYSTEM.................8
HEATED SEAT SWITCH
DESCRIPTION..........................8
OPERATION............................9
DIAGNOSIS AND TESTING
DRIVER HEATED SEAT SWITCH..........9
REMOVAL.............................10
INSTALLATION.........................10HEATED SEAT ELEMENTS
DESCRIPTION.........................11
OPERATION...........................11
DIAGNOSIS AND TESTING
HEATED SEAT ELEMENTS..............11
REMOVAL.............................12
INSTALLATION.........................12
HEATED SEAT SENSOR
DESCRIPTION.........................13
OPERATION...........................13
DIAGNOSIS AND TESTING
HEATED SEAT SENSOR................13
HEATED SEAT SYSTEM
DESCRIPTION
Vehicles with the heated seat option can be visu-
ally identified by the two separate heated seat
switches located in the instrument panel center
stack, just above the radio (Fig. 1). The heated seat
system allows the front seat driver and passenger to
select from two different levels of supplemental elec-
trical seat heating (HI/LO), or no seat heating to suit
their individual comfort requirements. The heated
seat system for this vehicle includes the following
major components:
²Heated Seat Elements- Four heated seat ele-
ments are used per vehicle, two for each front seat.
One heated seat element is integral to each front
seat trim cover, one in the seat back and one in the
seat bottom (cushion). Service replacement heating
elements are available, (Refer to 8 - ELECTRICAL/
HEATED SEATS/HEATED SEAT ELEMENT -
DESCRIPTION) for additional information.
²Heated Seat Modules- Two heated seat mod-
ules are used per vehicle. One module is mounted to
each of the seat cushion pans, located under the for-
ward edge of each front seat. (Refer to 8 - ELECTRI-
CAL/ELECTRONIC CONTROL MODULES/
MEMORY HEATED SEAT/MIRROR MODULE -
DESCRIPTION) for additional information.
²Heated Seat Sensors- Two heated seat sen-
sors are used per vehicle, one for each front seat. The
heated seat sensors are integral to each of the heated
seat bottoms (cushions).
²Heated Seat Switch- Two heated seat
switches are used per vehicle, one for the driver and
one for the passenger side front seats. The switches
are mounted in the instrument panel center stack.
(Refer to 8 - ELECTRICAL/HEATED SEATS/
DRIVER HEATED SEAT SWITCH - DESCRIPTION)
for additional information.
Fig. 1 HEATED SEAT SWITCH LOCATIONS
1 - HEATED SEAT SWITCHES
RSHEATED SEAT SYSTEM8G-7
Hard wired circuitry connects the heated seat sys-
tem components to each other through the electrical
system of the vehicle. These circuits may be con-
nected to each other, to the vehicle electrical system
and to the heated seat system components through
the use of a combination of soldered splices and
splice block connectors. Refer to the appropriate wir-
ing information for complete circuit schematic or con-
nector pin-out information.
OPERATION
The heated seat system components operate on
battery current received through a fuse in the Inte-
grated Power Module (IPM) on a fused ignition
switch output (run) circuit from the Body Control
Module (BCM). The system will only operate when
the ignition switch is in the On position. The heated
seat system will be turned Off automatically when-
ever the ignition switch is turned to any position
except On. Also, the heated seat system will not oper-
ate when the surface temperature of the seat cushion
cover at either heated seat sensor is above the
designed temperature set points of the system.
DIAGNOSIS AND TESTING
HEATED SEAT SYSTEM
The most efficient means of diagnosing the heated
seat system is by individual component. For diagno-
sis of a specific component refer to the following:
²Heated seat module, (Refer to 8 - ELECTRICAL/
ELECTRONIC CONTROL MODULES/MEMORY
HEATED SEAT/MIRROR MODULE - DIAGNOSIS
AND TESTING).
²Heated seat elements, (Refer to 8 - ELECTRI-
CAL/HEATED SEATS/HEATED SEAT ELEMENT -
DIAGNOSIS AND TESTING).
²Heated seat switch, (Refer to 8 - ELECTRICAL/
HEATED SEATS/DRIVER HEATED SEAT SWITCH
- DIAGNOSIS AND TESTING).
²Heated seat sensor, (Refer to 8 - ELECTRICAL/
HEATED SEATS/HEATED SEAT SENSOR - DIAG-
NOSIS AND TESTING).
Refer to the appropriate wiring information for
complete circuit schematic or connector pin-out infor-
mation.
HEATED SEAT SWITCH
DESCRIPTION
The heated seat switches are mounted in the
instrument panel center bezel (Fig. 2). The two three-
position rocker-type switches, one switch for each
front seat, are incorporated into one large switch
assembly that also includes the hazard, rear window
wiper and washer switches. Each heated seat switch
provides a resistor multiplexed signal to its respec-
tive Heated Seat Module (HSM) through separate
hard wired circuits. Each switch has an Off, Low,
and High position so that both the driver and the
front seat passenger can select a preferred seat heat-
ing mode. Each switch has two Light-Emitting
Diodes (LED) which light to indicate that the heater
for the seat is turned on.
The heated seat switches and their LEDs cannot
be repaired. If either switch or LED is faulty or dam-
aged, the entire switch assembly must be replaced.
Fig. 2 HEATED SEAT SWITCH LOCATION
1 - HEATED SEAT SWITCHES
8G - 8 HEATED SEAT SYSTEMRS
HEATED SEAT SYSTEM (Continued)