1&4). There should be continuity. If OK, (Refer to 8 -
ELECTRICAL/ELECTRONIC CONTROL MOD-
ULES/MEMORY HEATED SEAT/MIRROR MOD-
ULE - DIAGNOSIS AND TESTING) for complete
system testing procedures. If not OK, install a
replacement heated seat cushion element, (Refer to 8
- ELECTRICAL/HEATED SEATS/HEATED SEAT
ELEMENT - INSTALLATION).
SEAT BACK ELEMENT
(1) From under the vehicle, remove the appropri-
ate seats four retaining nuts.
(2) From inside the vehicle, pull the seat up and
off the mounting studs and lay it back, up against
one of the rear seats.
(3) Locate the heated seat module, attached to the
bottom of the seat cushion pan. Remove the heated
seat module from the seat cushion pan. Do not dis-
connect the electrical connectors at this time.
(4) Locate and disconnect the gray 2-way electrical
connector, connected to the heated seat module.
(5) Check for continuity between the two circuit
cavities of the 2-way wire harness connector. There
should be continuity. If OK, (Refer to 8 - ELECTRI-
CAL/ELECTRONIC CONTROL MODULES/MEM-
ORY HEATED SEAT/MIRROR MODULE -
DIAGNOSIS AND TESTING) for complete system
testing procedures. If not OK, install a replacement
heated seat back element, (Refer to 8 - ELECTRI-
CAL/HEATED SEATS/HEATED SEAT ELEMENT -
INSTALLATION).
REMOVAL
NOTE: Do not remove the factory installed heating
elements from the seat or seat back cushions. The
original element is permanently attached and can-
not be removed without permanent damage. The
replacement heating element is designed to be
applied directly on top of the factory installed heat-
ing element.
(1) Disconnect and isolate the battery negative
cable.
(2) Remove the appropriate seat cushion or seat
back trim cover.
(3) Disconnect the inoperative heated seat cushion
or seat back element electrical connectors (Fig. 6).
(4) Locate the wires leading from the inoperative
heating element and cut them off flush with the edge
of the original heating element.
INSTALLATION
(1) Peel off the adhesive backing on the back of the
replacement heating element and stick directly on
top of the factory installed heating element (Fig. 7).CAUTION: During the installation of the replace-
ment heating element, be careful not to fold or
crease the element assembly. Folds or creases will
cause premature failure.
Fig. 6 HEATING ELEMENT INSTALLED - TYPICAL
1 - SEAT BACK WIRE HARNESS
2 - HEATED SEAT WIRE HARNESS CONNECTOR
3 - HEATED SEAT CUSHION ELEMENT
Fig. 7 HEATING ELEMENT INSTALLATION
1 - ORIGINAL (INOPERATIVE) HEATING ELEMENT
2 - REPLACEMENT HEATING ELEMENT
8G - 12 HEATED SEAT SYSTEMRS
HEATED SEAT ELEMENTS (Continued)
(2) Connect the new heating element electrical
connectors (Fig. 8).Passenger seat shown, driver
seat similar.
(3) Connect the battery negative cable.
(4) Verify heated seat system operation.
(5) Install the appropriate seat cushion or seat
back trim cover.
NOTE: Make certain the seat wire harness is cor-
rectly routed through the seat and seat back. The
excess wire between the cushion and back ele-
ments should be securely tucked between the rear
of the cushion foam and the rear carpet flap of the
trim cover.HEATED SEAT SENSOR
DESCRIPTION
Two heated seat sensors are used per vehicle, one
in each front seat cushion heating element. The
heated seat temperature sensor is a Negative Tem-
perature Coefficient (NTC) thermistor.
The heated seat sensors cannot be repaired or
adjusted and if found to be faulty, the complete
heated seat cushion element must be replaced.
OPERATION
The temperature sensor is a Negative Temperature
Coefficient (NTC) thermistor. When the temperature
of the seat cushion cover rises, the resistance of the
sensor decreases. The heated seat module supplies a
five-volt current to one side of each sensor, and mon-
itors the voltage drop through the sensor on a return
circuit. The heated seat module uses this tempera-
ture sensor input to monitor the temperature of the
seat, and regulates the current flow to the seat heat-
ing elements accordingly.
DIAGNOSIS AND TESTING
HEATED SEAT SENSOR
Refer to the appropriate wiring information for
complete circuit schematic or connector pin-out infor-
mation.
(1) Disconnect and isolate the battery negative
cable. Disconnect the green 4-way heated seat mod-
ule wire harness connector.
(2) Using an ohmmeter, check the resistance
between cavities 2 and 3. The sensor resistance
should be between 50 kilohms at 15É C (60É F) and 2
kilohms at 30É C (85É F). If not OK, replace the
faulty seat element and sensor assembly.
Fig. 8 HEATED SEAT WIRE HARNESS ROUTING
1 - SEAT BACK HEATED SEAT WIRE HARNESS
2 - PASSENGER SEAT BACK
3 - SEAT BACK ELEMENT CONNECTOR
4 - SEAT CUSHION ELEMENT CONNECTOR
RSHEATED SEAT SYSTEM8G-13
HEATED SEAT ELEMENTS (Continued)
HORN
TABLE OF CONTENTS
page page
HORN SYSTEM
DESCRIPTION..........................1
OPERATION............................1
DIAGNOSIS AND TESTING
HORN SYSTEM........................1
HORN
DIAGNOSIS AND TESTING
HORN...............................3REMOVAL.............................4
INSTALLATION..........................4
HORN SWITCH
DESCRIPTION..........................4
HORN SYSTEM
DESCRIPTION
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAG, REFER TO ELECTRICAL, RESTRAINTS FOR
SAFETY PRECAUTIONS. DISCONNECT THE NEGA-
TIVE CABLE FROM THE BATTERY BEFORE SER-
VICING COMPONENTS INVOLVING THE AIRBAG
SYSTEM. ACCIDENTAL DEPLOYMENT OF AIRBAG
AND PERSONAL INJURY CAN RESULT.
The horn circuit consists of a horn switch, clock-
spring, horn relay, horns and Integrated Power Mod-
ule (IPM). The horn switch is a membrane switch
located in the airbag trim cover. The horns are
located forward of the left front wheel behind the
bumper fascia.
OPERATION
The horn relay plugs into the Integrated Power
Module (IPM) which is located in the engine com-
partment. For circuit information and component
locations, refer to the appropriate wiring information.
The wiring information includes wiring diagrams,
proper wire and connector repair procedures, details
of wire harness routing and retention, connector pin-
out information and location views for the various
wire harness connectors, splices and grounds.
The horns will not function if the switch is
ªCLOSEDº for more than 30 seconds. Once the
switch is ªOPENº, a 20±30 second delay will occur
before the horns are functional again.
DIAGNOSIS AND TESTING
HORN SYSTEM
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, REFER TO ELECTRICAL, RESTRAINTS
BEFORE ATTEMPTING ANY STEERING WHEEL,
STEERING COLUMN, OR INSTRUMENT PANEL
COMPONENT DIAGNOSIS OR SERVICE. FAILURE
TO TAKE THE PROPER PRECAUTIONS COULD
RESULT IN ACCIDENTAL AIRBAG DEPLOYMENT
AND POSSIBLE PERSONAL INJURY.
Refer to Horn System Test below. If the horn does
not sound, check horn fuse located in the Integrated
Power Module (IPM). If the fuse is blown, replace
with the correct fuse. If the horns fail to sound and
the new fuse blows when depressing the horn switch,
a short circuit in the horn or the horn wiring
between the fuse terminal and the horn is responsi-
ble, or a defective horn switch allowed the horn to
burn out is responsible.
If the fuse is OK, test horn relay.
If the relay is OK, test horn.
CAUTION: Continuous sounding of horn may
cause horn failure.
Should the horn sound continuously, unplug the
horn relay from IPM.
Refer to the appropriate wiring information.
RSHORN8H-1
CONDITION POSSIBLE CAUSE CORRECTION
(6) CLOCKSPRING
INOPERATIVE.(6) REPLACE CLOCKSPRING.
(7) FRONT CONTROL
MODULE INOPERATIVE.(7) REFER TO ELECTRONIC CONTROL
MODULES/FRONT CONTROL MODULE.
FUSE BLOWS WHEN HORN SOUNDS (1) SHORT CIRCUIT IN
HORN OR HORN WIRING.(1) REMOVE HORN RELAY, CHECK
FOR SHORTED HORN OR HORN
WIRING. DISCONNECT HORN WIRE
HARNESS TO ISOLATE SHORT AND
REPAIR AS NECESSARY.
(2) CLOCKSPRING
INOPERATIVE.(2) REPLACE CLOCKSPRING.
FUSE BLOWS WITHOUT BLOWING
HORN(1) SHORT CIRCUIT. (1) REMOVE RELAY, INSTALL NEW
FUSE, IF FUSE DOES NOT BLOW
REPLACE HORN RELAY. IF FUSE
BLOWS WITH RELAY REMOVED,
CHECK FOR SHORT TO GROUND
WITH OHMMETER ON CIRCUIT
BETWEEN TERMINALS 30 & 86 AND
THE FUSE TERMINAL. REPAIR AS
NECESSARY.
(2) CLOCKSPRING
INOPERATIVE.(2) REPLACE CLOCKSPRING.
HORN
DIAGNOSIS AND TESTING
HORN
HORN
(1) Disconnect wire connector at horn.
(2) Using a voltmeter, connect one lead to ground
terminal and the other lead to the positive wire ter-
minal (Fig. 1).
(3) Depress the horn switch, battery voltage
should be present.
(4) If no voltage, refer toHORNS WILL NOT
SOUND. If voltage is OK, go to step Step 5.
(5) Using ohmmeter, test ground wire for continu-
ity to ground.
(6) If no ground repair as necessary.
(7) If wires test OK and horn does not sound,
replace horn.
HORNS SOUND CONTINUOUSLY
CAUTION: Continuous sounding of horns may
cause relay to fail.
The horn switch (membrane) sometimes can be the
cause without the switch being depressed.(1) Remove the horn relay from the intelligent
power module.
(2)
Using a continuity tester, test continuity from the
X3 cavity of the horn relay to ground. Refer to the
appropriate wiring information. The wiring information
includes wiring diagrams, proper wire and connector
repair procedures, details of wire harness routing and
retention, connector pin-out information and location
views for the various wire harness connectors, splices
and grounds.
(a)If continuity is detected, proceed to step Step 3.
(b) If NO continuity, replace the horn relay.
(3) Remove the airbag trim cover from the steering
wheel and disengage horn connector.
(4) Install horn relay into Integrated Power Mod-
ule (IPM).
(a)
If horn does not sound, replace airbag trim
cover.
(b) If horn sounds, repair grounded X3 circuit
from IPM to clockspring in the steering column.
HORNS WILL NOT SOUND
Check horn fuse#8intheIPM. If fuse is blown,
check for a shorted switch in the airbag module. and
refer to FUSE BLOWN section. If fuse is OK, refer to
FUSE OK section.
FUSE BLOWN
(1) Verify condition of battery terminals and volt-
age, (Refer to 8 - ELECTRICAL/BATTERY SYSTEM
RSHORN8H-3
HORN SYSTEM (Continued)
- DIAGNOSIS AND TESTING). If battery connec-
tions and battery charge is OK proceed to Step 2.
(2) Using a voltmeter, test for battery voltage at
both sides of horn fuse 7. If voltage is OK, on both
sides of fuse, proceed to Fuse OK. If voltage is OK,
on one side of fuse, the fuse is blown, proceed to Step
3.
(3) Using a suitable ammeter in place of the fuse,
test amperage draw of the horn circuit. If amperage
draw is greater than 20 amps without the horn
switch depressed, a grounded circuit exists between
the fuse and the horn relay. Proceed to Step 4. If
amperage draw is greater than 20 amps with the
horn switch depressed, a grounded circuit exists
between the horn relay and the horn. Proceed to step
Step 5.
(4) Remove the horn relay from the IPM. If the
amperage draw drops to 0 amps, the horn switch or
circuit is shorted. If the amperage draw does not
drop to 0 amps, repair short at the IPM.
(5) Disengage a wire connector from one of the
horns. If amperage drops and the connected horn
sounds, replace the faulty horn. If amperage does not
drop with both horns disconnected and the horn
switch depressed, proceed to Step 6.
(6) Using a continuity tester, with the horns dis-
connected test continuity of the X2 cavity of the horn
relay to ground. If continuity is detected, the circuit
is grounded between the Junction Block and the
horns. Locate and repair pinched harness.
FUSE OK
(1) Remove the horn relay from the intelligent
power module.
(2) Using a continuity tester, Depress horn switch
and test continuity from the X3 cavity of the horn
relay to ground.
(a) If continuity is detected, proceed to Step 3.
(b) If NO continuity, proceed to Step 4.
(3) Using a suitable jumper wire, jump across the
fuse F62 cavity and the X2 cavity of the horn relay in
the Junction Block.
(a) If the horn sounds, replace the horn relay.
(b) If the horn does not sound, proceed to Step 4.
(4) Remove airbag trim cover from steering wheel.
Refer to ELECTRICAL, RESTRAINTS.
(5) Test continuity across horn switch connectors
with horn switch depressed.
(a) If continuity is detected, repair open circuit
between the relay and the horn switch.
(b) If NO continuity, replace airbag trim cover.
(6) Install horn relay into intelligent power mod-
ule.
(7) Disengage wire connectors from horns.(8) Using a voltmeter, with the horn switch
depressed test voltage across horn connector termi-
nals of the wire harness (Fig. 1).
(a) If voltage is detected, replace horns.
(b) If NO voltage, proceed to step Step 9.
(9) With the horn switch depressed, test for volt-
age between the X2 circuit and ground.
(a) If voltage OK, repair system ground at right
cowl area.
(b) If NO voltage, repair open X2 circuit between
the relay and the horns.
REMOVAL
(1) Disconnect and isolate the battery negative
cable.
(2) Hoist and support the front of the vehicle on
safety stands.
(3) From behind the front fascia and forward of
the left front wheel, disconnect the wire connectors
from horn.
(4) Remove the mounting bracket attaching nut
from the bottom of radiator closure panel. Do not
remove the horn from mounting bracket.
(5) Separate the horn(s) from vehicle.
INSTALLATION
(1) Install the horns to the vehicle.
(2) Install the mounting bracket fastener.
(3) Reconnect the wire connectors to the horns.
(4) Lower the vehicle.
(5) Reconnect the battery negative cable.
HORN SWITCH
DESCRIPTION
The horn switch is molded into the airbag trim
cover. The horn switch can not be serviced separately.
For service procedures (Refer to 8 - ELECTRICAL/
RESTRAINTS/AIRBAG COVER - REMOVAL).
Fig. 1 Horn Connector
8H - 4 HORNRS
HORN (Continued)
FIRING ORDERAUTO SHUT DOWN RELAY
DESCRIPTION
The relay is located in the Power Distribution Cen-
ter (PDC). For the location of the relay within the
PDC, refer to the PDC cover for location. Check elec-
trical terminals for corrosion and repair as necessary
OPERATION
The engine switched battery (NGC vehicles)
informs the PCM when the ASD relay energizes. A 12
volt signal at this input indicates to the PCM that
the ASD has been activated. This input is also used
to power certain drivers on NGC vehicles.
When energized, the ASD relay on NGC vehicles
provides power to operate the injectors, ignition coil,
generator field, O2 sensor heaters (both upstream
and downstream), evaporative purge solenoid, EGR
solenoid (if equipped) wastegate solenoid (if
equipped), and NVLD solenoid (if equipped).
The ASD relay also provides a sense circuit to the
PCM for diagnostic purposes. If the PCM does not
receive 12 volts from this input after grounding the
control side of the ASD relay, it sets a Diagnostic
Trouble Code (DTC). The PCM energizes the ASD
any time there is an engine speed that exceeds a pre-
determined value (typically about 50 rpm). The ASD
relay can also be energized after the engine has been
turned off to perform an O2 sensor heater test, if
vehicle is equipped with OBD II diagnostics.
As mentioned earlier, the PCM energizes the ASD
relay during an O2 sensor heater test. On NGC vehi-
cles it checks the O2 heater upon vehicle start. The
PCM still operates internally to perform several
checks, including monitoring the O2 sensor heaters.
FIRING ORDER 2.4L
Firing Order 1-2-3-4-5-6 3.3/3.8L
1 - Electrical Connector
RSIGNITION CONTROL8I-3
IGNITION CONTROL (Continued)
REMOVAL
REMOVAL - 2.4L
The camshaft position sensor is mounted to the
rear of the cylinder head.
(1) Remove the negative battery cable.
(2) Disconnect electrical connectors from the cam-
shaft position sensor (Fig. 3).
(3) Remove camshaft position sensor mounting
screws. Remove sensor.
(4) Loosen screw attaching target magnet to rear
of camshaft and remove magnet (Fig. 4).
REMOVAL - 3.3/3.8L
(1) Disconnect the negative battery cable.
(2) Remove the air box cover and inlet tube (Fig.
5).
(3) Disconnect camshaft position sensor electrical
connector from the wiring harness connector (Fig. 6).
(4) Remove bolt holding sensor.
(5) Rotate sensor away from block.
Fig. 3 EGR/CAM SENSOR 2.4L
Fig. 4 Target Magnet Removal/Installation
1 - TARGET MAGNET
2 - MOUNTING BOLT
3 - REAR OF CYLINDER HEAD
Fig. 5 AIR BOX COVER
Fig. 6 CAMSHAFT POSITION SENSOR
RSIGNITION CONTROL8I-5
CAMSHAFT POSITION SENSOR (Continued)
(6) Pull sensor up out of the chain case cover.Do
not pull on the sensor wiring.There is an O-ring
on the body of the sensor. The O-ring may make
removal difficult. A light tap to top of sensor prior to
removal may reduce force needed for removal.
INSTALLATION
INSTALLATION - 2.4L
The target magnet has locating dowels that fit into
machined locating holes in the end of the camshaft
(Fig. 7).
(1) Install target magnet in end of camshaft.
Tighten mounting screw to 3 N´m (30 in. lbs.) torque.
Over torqueing could cause cracks in magnet. If mag-
net cracks replace it.
(2) Install camshaft position sensor. Tighten sensor
mounting screws to 12.9 N´m (115 in. lbs.) torque.
(3) Carefully attach electrical connector to cam-
shaft position sensor.
(4) Connect the negative battery cable.
INSTALLATION - 3.3/3.8L
If the removed sensor is reinstalled, clean off
the old spacer on the sensor face. A NEW
SPACER must be attached to the face before
installation.Inspect O-ring for damage, replace if
necessary. If the sensor is being replaced, confirm
that the paper spacer is attached to the face and
O-ring is positioned in groove of the new sensor (Fig.
8).
(1) Apply a couple drops of clean engine oil to the
O-ring prior to installation.
(2) Install sensor in the chain case cover and
rotate into position.(3) Push sensor down until contact is made with
the camshaft gear. While holding the sensor in this
position, install and tighten the retaining bolt 14
N´m (125 in. lbs.) torque.
(4) Connect camshaft position sensor electrical
connector to harness connector.
(5) Install the air box cover and inlet hose (Fig. 5).
(6) Connect the negative battery cable.
IGNITION COIL
DESCRIPTION
The ignition coil assembly consists of 2 or 3 inde-
pendent coils molded together (Fig. 9) or (Fig. 10).
The coil assembly for the 3.3/3.8L is mounted on the
intake manifold. The coil assembly for the 2.4L is
mounted on the cylinder head cover. Spark plug
cables route to each cylinder from the coil.
OPERATION
The coil fires two spark plugs every power stroke.
One plug is the cylinder under compression, the
other cylinder fires on the exhaust stroke. The Pow-
ertrain Control Module (PCM) determines which of
the coils to charge and fire at the correct time.
The Auto Shutdown (ASD) relay provides battery
voltage to the ignition coil. The PCM provides a
ground contact (circuit) for energizing the coil. When
the PCM breaks the contact, the magnetic energy in
the coil transfers to the secondary causing the spark.
The PCM will de-energize the ASD relay if it does
not receive the crankshaft position sensor and cam-
shaft position sensor inputs. Refer to Auto Shutdown
(ASD) RelayÐPCM Output, in this section for relay
operation.
Fig. 7 Target Magnet Installation
1 - LOCATING DOWELS
2 - LOCATING HOLES (2)
Fig. 8 Camshaft Position Sensor and Spacer
1 - ELECTRICAL CONNECTOR
2 - O-RING
3 - PAPER SPACER
8I - 6 IGNITION CONTROLRS
CAMSHAFT POSITION SENSOR (Continued)