
3.2.2 ECM OPERATING MODES
As input signals to the ECM change, the ECM
adjusts its response to the output devices. For
example, the ECM must calculate a different fuel
quantity and fuel timing for engine idle condition
than it would for a wide open throttle condition.
There are several different modes of operation that
determine how the ECM responds to the various
input signals.
Ignition Switch On (Engine Off)
When the ignition is turned on the ECM activates
the glow plug relay for a time period that is deter-
mined by engine coolant temperature, intake air
temperature and battery voltage.
Engine Start-Up Mode
The ECM uses the intake air temperature sensor,
engine temperature sensor and the crankshaft po-
sition sensor (engine speed) inputs to determine
fuel injection quantity.
Normal Driving Modes
Engine idle, warm-up, acceleration, deceleration
and wide open throttle modes are controlled based
on all of the sensor inputs to the ECM. The ECM
uses these sensor inputs to adjust fuel quantity and
fuel injector timing. EGR valve control is performed
using feedback from the oxygen sensor. An oxygen
sensor is located in the exhaust manifold to sample
oxygen content exiting the engine cylinders. The
ECM uses the O2 sensor, along with other sensor
inputs, to govern the amount of exhaust gas recir-
culation to reduce HC (HydroCarbons) and CO
(Carbon Monoxide). Engine coolant is routed
through the base of the EGR valve to provide
additional cooling of the exhaust gas, which further
helps the reductions of emissions. The EGR valve
has a self-cleaning function. When the engine is
shut off, the EGR valve rotates twice to reduce
carbon deposits at the valve seat.
Overheat Production Mode
If the engine temperature is above 105ÉC (221ÉF)
and vehicle speed is above 40 km/h (25 MPH) the
ECM will limit fuel quantity for engine protection.
Limp-In Mode
The ECM utilizes different degrees of engine
limp-in. The ECM is able to limit engine rpm,
engine power output (turbo boost reduction), acti-
vate engine cooling fan or all of these functions
based on the type of fault that is detected. Critical
engine performance faults such as accelerator pedal
position sensor fault will result in a fixed idle speed
of approximately 680 rpm regardless of actual pedalposition. Other less critical faults will result in
power reduction throughout the full range of driv-
ing conditions.
Overspeed Detection Mode
If the ECM detects engine RPM that exceeds
5200 RPM, the ECM will set a DTC in memory,
limit engine RPM to no more than 2500 RPM, and
illuminate the MIL until the DTC is cleared.
After-Run Mode
The ECM transfers RAM information to ROM
and performs an Input/Output state check.
3.2.3 MONITORED CIRCUITS
The ECM is able to monitor and identify most
driveability related trouble conditions. Some cir-
cuits are directly monitored through ECM feedback
circuitry. In addition, the ECM monitors the voltage
state of some circuits and compares those states
with expected values. Other systems are monitored
indirectly when the ECM conducts a rationality test
to identify problems.
Although most subsystems of the engine control
module are either directly or indirectly monitored,
there may be occasions when diagnostic trouble
codes are not immediately identified. For a trouble
code to set, a specific set of conditions must occur
and unless these conditions occur, a DTC will not
set.
3.2.4 SKREEM OVERVIEW
The sentry key remote entry module system
(SKREEM) is designed to prevent unauthorized
vehicle operation. The system consists of a sentry
key remote entry module (SKREEM), ignition
key(s) equipped with a transponder chip and the
ECM. When the ignition switch is turned on, the
SKREEM interrogates the ignition key. If the igni-
tion key is Valid or Invalid, the SKREEM sends a
message to the ECM indicating ignition key status.
Upon receiving this message the ECM will termi-
nate engine operation or allow the engine to con-
tinue to operate.
3.2.5 SKREEM ON-BOARD DIAGNOSTICS
The SKREEM has been programmed to transmit
and monitor many different coded messages as well
as CAN Bus messages. This monitoring is called
On-Board Diagnostics. Certain criteria must be met
for a DTC to be entered into SKREEM memory. The
criteria may be a range of; input voltage, CAN Bus
message or coded messages to the SKREEM. If all
the criteria for monitoring a circuit or function are
met and a fault is detected, a DTC will be stored in
the SKREEM memory and the START ERROR indi-
cator will be turned on in the instrument cluster.
2
GENERAL INFORMATION

INSTALLATION
(1) Install the battery hold down brackets.
(2) Install the two nuts that secure the battery
hold down brackets to the battery tray. Tighten to 70
in. lbs.
BATTERY CABLES
DESCRIPTION
The battery cables are large gauge, stranded cop-
per wires sheathed within a heavy plastic or syn-
thetic rubber insulating jacket. The wire used in the
battery cables combines excellent flexibility and reli-
ability with high electrical current carrying capacity.
The battery cables cannot be repaired and, if dam-
aged or faulty they must be replaced. Both the bat-
tery positive and negative cables are available for
service replacement only as a unit with the battery
positive cable wire harness or the battery negative
cable wire harness, which may include portions of
the wiring circuits for the generator and other com-
ponents on some models.
The battery cables feature a stamped brass clamp-
ing type female battery terminal crimped onto one
end of the battery cable wire and then solder-dipped.
A square headed pinch-bolt and hex nut are installed
at the open end of the female battery terminal clamp.
The battery positive cable also includes a red molded
rubber protective cover for the female battery termi-
nal clamp. Large eyelet type terminals are crimped
onto the opposite end of the battery cable wire and
then solder-dipped. The battery positive cable wires
have a red insulating jacket to provide visual identi-
fication and feature a larger female battery terminal
clamp to allow connection to the larger battery posi-
tive terminal post. The battery negative cable wires
have a black insulating jacket and a smaller female
battery terminal clamp.
OPERATION
The battery cables connect the battery terminal
posts to the vehicle electrical system. These cables
also provide a return path for electrical current gen-
erated by the charging system for restoring the volt-
age potential of the battery. The female battery
terminal clamps on the ends of the battery cable
wires provide a strong and reliable connection of the
battery cable to the battery terminal posts. The ter-
minal pinch bolts allow the female terminal clamps
to be tightened around the male terminal posts on
the top of the battery. The eyelet terminals secured
to the ends of the battery cable wires opposite the
female battery terminal clamps provide secure and
reliable connection of the battery to the vehicle elec-
trical system.
DIAGNOSIS AND TESTING - BATTERY CABLES
A voltage drop test will determine if there is exces-
sive resistance in the battery cable terminal connec-
tions or the battery cables. If excessive resistance is
found in the battery cable connections, the connec-
tion point should be disassembled, cleaned of all cor-
rosion or foreign material, then reassembled.
Following reassembly, check the voltage drop for the
battery cable connection and the battery cable again
to confirm repair.
When performing the voltage drop test, it is impor-
tant to remember that the voltage drop is giving an
indication of the resistance between the two points at
which the voltmeter probes are attached.EXAM-
PLE:When testing the resistance of the battery pos-
itive cable, touch the voltmeter leads to the battery
positive cable terminal clamp and to the battery pos-
itive cable eyelet terminal at the starter solenoid
B(+) terminal stud. If you probe the battery positive
terminal post and the battery positive cable eyelet
terminal at the starter solenoid B(+) terminal stud,
you are reading the combined voltage drop in the
battery positive cable terminal clamp-to-terminal
post connection and the battery positive cable.
VOLTAGE DROP TEST
WARNING: IF THE BATTERY SHOWS SIGNS OF
FREEZING, LEAKING, LOOSE POSTS, OR LOW
ELECTROLYTE LEVEL, DO NOT TEST, ASSIST-
BOOST, OR CHARGE. THE BATTERY MAY ARC
INTERNALLY AND EXPLODE. PERSONAL INJURY
AND/OR VEHICLE DAMAGE MAY RESULT.
WARNING: EXPLOSIVE HYDROGEN GAS FORMS IN
AND AROUND THE BATTERY. DO NOT SMOKE,
USE FLAME, OR CREATE SPARKS NEAR THE BAT-
TERY. PERSONAL INJURY AND/OR VEHICLE DAM-
AGE MAY RESULT.
WARNING: THE BATTERY CONTAINS SULFURIC
ACID, WHICH IS POISONOUS AND CAUSTIC. AVOID
CONTACT WITH THE SKIN, EYES, OR CLOTHING.
IN THE EVENT OF CONTACT, FLUSH WITH WATER
AND CALL A PHYSICIAN IMMEDIATELY. KEEP OUT
OF THE REACH OF CHILDREN.
WARNING: IF THE BATTERY IS EQUIPPED WITH
REMOVABLE CELL CAPS, BE CERTAIN THAT EACH
OF THE CELL CAPS IS IN PLACE AND TIGHT
BEFORE THE BATTERY IS RETURNED TO SER-
VICE. PERSONAL INJURY AND/OR VEHICLE DAM-
AGE MAY RESULT FROM LOOSE OR MISSING
CELL CAPS.
8F - 14 BATTERY SYSTEMVA

The airbag used in this model is a Next Genera-
tion-type that complies with revised federal airbag
standards to deploy with less force than those used
in some prior models. A radial deploying fabric cush-
ion with internal tethers is used. The airbag inflator
is a solid fuel, pyrotechnic-type unit with four studs
and is secured by four hex nuts to four studs on the
airbag cushion retainer ring to the back of the
stamped metal airbag housing. A keyed connector
receptacle on the driver airbag inflator connects the
inflator initiator to the vehicle electrical system
through a yellow-jacketed, two-wire pigtail harness of
the clockspring.
The driver airbag and trim cover unit cannot be
repaired, and must be replaced if deployed, faulty, or
in any way damaged.
OPERATION
The driver airbag is deployed by electrical signals
generated by the Airbag Control Module (ACM)
through the driver airbag squib circuit to the initia-
tor in the airbag inflator (Fig. 20). When the ACM
sends the proper electrical signal to the initiator the
electrical energy generates enough heat to initiate a
small pyrotechnic charge which, in turn, ignites
chemical pellets within the inflator. Once ignited,
these chemical pellets burn rapidly and produce a
large quantity of inert gas. The inflator is sealed to
the back of the airbag housing and a diffuser in the
inflator directs all of the inert gas into the airbag
cushion, causing the cushion to inflate. As the cush-
ion inflates, the driver airbag trim cover will split at
predetermined breakout lines, then fold back out of
the way. Following an airbag deployment, the airbag
cushion quickly deflates by venting the inert gas
towards the instrument panel through filtered vents
within the fabric used to construct the back (steering
wheel side) panel of the airbag cushion.
Some of the chemicals used to create the inert gas
may be considered hazardous while in their solid
state before they are burned, but they are securely
Fig. 19 Driver Airbag Housing
1 - HOUSING
2 - INFLATOR
3 - CONNECTOR RECEPTACLE
4 - TRIM COVER
Fig. 20 Driver Airbag Operation
1 - TRIM COVER
2 - INFLATOR
3 - INITIATOR
4 - CUSHION (FOLDED)
5 - STEERING WHEEL
VARESTRAINTS 8O - 17

(3) If the vehicle is so equipped, snap the plastic
cover over the screw that secures the front seat belt
buckle lower anchor to the inboard side of the seat
frame.
(4) On the driver side only, reconnect the seat belt
switch pigtail wire to the vehicle wire harness and
push the joined connectors through the clearance
hole in the seat riser cover.
(5) On the driver side only, route and secure the
seat belt switch pigtail wire to the seat frame with
wire ties.
PASSENGER AIRBAG
DESCRIPTION
The rearward facing surface of the injection
molded, thermoplastic passenger airbag door is the
most visible part of the optional passenger airbag
(Fig. 27). The passenger airbag door is located above
the glove box opening in front of the front seat pas-
senger seating position on the instrument panel. The
upper and lower edges of the airbag door are secured
by a snap-fit to molded plastic clips. The two clips at
the top are each secured by a screw to the instru-
ment panel base trim, while the clips at the bottom
are integral to the panel that surrounds the passen-
ger airbag door opening in the instrument panel base
trim. The airbag door is also secured to the airbag
housing by two wide woven straps that serve as
hinges for the door upon an airbag deployment.
Located behind the passenger airbag door is the
passenger airbag unit (Fig. 28). The airbag housing
is constructed of a long U-shaped aluminum extru-
sion with two stamped steel end plates. A stepped
flange that extends from the back of the extrusion
serves as the airbag mounting flange. This mountingflange is secured with screws to a stamped steel air-
bag mounting bracket that is secured with screws to
the tubular steel instrument panel structural support
above the glove box opening. The end plates are
secured to each side of the passenger airbag housing
with screws.
The passenger airbag unit used in this model is a
Next Generation-type that complies with revised fed-
eral airbag standards to deploy with less force than
those used in some prior models. The airbag housing
contains the folded airbag cushion, the airbag
retainer, and the airbag inflator. The airbag is a rect-
angular fabric cushion. The airbag inflator is a solid
fuel, pyrotechnic-type unit that is secured to and
sealed within the airbag housing along with the
folded airbag cushion. The inflator initiator connector
receptacle is connected to the vehicle electrical sys-
tem through a dedicated take out of the vehicle wire
harness with a yellow connector insulator.
The passenger airbag and airbag door unit cannot
be repaired, and must be replaced if deployed, faulty
or in any way damaged.
OPERATION
The passenger airbag is deployed by an electrical
signal generated by the Airbag Control Module
(ACM) through the passenger airbag squib circuits to
the initiator in the airbag inflator. When the ACM
sends the proper electrical signal to the initiator the
electrical energy generates enough heat to initiate a
small pyrotechnic charge which, in turn, ignites
chemical pellets within the inflator. Once ignited,
these chemical pellets burn rapidly and produce a
large quantity of inert gas. The inflator is sealed to
the back of the airbag housing and a diffuser in the
Fig. 27 Passenger Airbag Door
1 - INSTRUMENT PANEL TRAY
2 - PASSENGER AIRBAG DOOR
3 - GLOVE BOX DOOR
Fig. 28 Passenger Airbag Unit
1 - DOOR
2 - CLIP (2)
3 - HOUSING
4 - CONNECTOR RECEPTACLE
5 - END PLATE (2)
8O - 24 RESTRAINTSVA

in any way damaged. Once a side curtain airbag has
been deployed, the complete airbag unit and all other
visibly damaged components must be replaced.
OPERATION
Each side curtain airbag is deployed individually
by an electrical signal generated by the Airbag Con-
trol Module (ACM) to which it is connected through
left or right curtain airbag line 1 and line 2 (or
squib) circuits. The hybrid-type inflator assembly for
each airbag contains a small canister of highly com-
pressed inert gas. When the ACM sends the proper
electrical signal to the airbag inflator, the electrical
energy creates enough heat to ignite chemical pellets
within the inflator. Once ignited, these chemicals
burn rapidly and produce the pressure necessary to
rupture a containment disk in the inert gas canister.
The inflator and inert gas canister are sealed and
connected to a tubular manifold so that all of the
released gas is directed into the folded side curtain
airbag cushion, causing the cushion to inflate.
As the airbag cushion inflates it will split the gar-
nish molding at a predetermined breakout line and
drop down from the roof rail along the side glass and
body pillars to form a curtain-like cushion to protect
the vehicle occupants during a side impact collision.
The front tether keeps the front portion of the side
curtain bag taut, thus ensuring that the bag will
deploy in the proper position. Following the airbag
deployment, the airbag cushion quickly deflates by
venting the inert gas through the loose weave of the
cushion fabric, and the deflated cushion hangs down
loosely from the roof rail.
REMOVAL
The following procedure is for replacement of a
faulty or damaged side curtain airbag. If the airbag
is faulty or damaged, but not deployed, review the
recommended procedures for handling non-deployed
supplemental restraints. (Refer to 8 - ELECTRICAL/
RESTRAINTS - STANDARD PROCEDURE - HAN-
DLING NON-DEPLOYED SUPPLEMENTAL
RESTRAINTS). If the side curtain airbag has been
deployed, review the recommended procedures for
service after a supplemental restraint deployment
before removing the airbag from the vehicle. (Refer to
8 - ELECTRICAL/RESTRAINTS - STANDARD PRO-
CEDURE - SERVICE AFTER A SUPPLEMENTAL
RESTRAINT DEPLOYMENT).
WARNING: To avoid personal injury or death, on
vehicles equipped with airbags, disable the supple-
mental restraint system before attempting any
steering wheel, steering column, airbag, seat belt
tensioner, impact sensor, or instrument panel com-
ponent diagnosis or service. Disconnect and isolate
the battery negative (ground) cable, then wait two
minutes for the system capacitor to dischargebefore performing further diagnosis or service. This
is the only sure way to disable the supplemental
restraint system. Failure to take the proper precau-
tions could result in accidental airbag deployment.
WARNING: To avoid personal injury or death, when
removing a deployed airbag, rubber gloves, eye
protection, and a long-sleeved shirt should be
worn. There may be deposits on the airbag unit and
other interior surfaces. In large doses, these depos-
its may cause irritation to the skin and eyes.
WARNING: To avoid personal injury or death, use
extreme care to prevent any foreign material from
entering the side curtain airbag, or becoming
entrapped between the side curtain airbag cushion
and the roof rail garnish molding. Failure to
observe this warning could result in occupant inju-
ries upon airbag deployment.
(1) Disconnect and isolate the battery negative
cable. Wait two minutes for the system capacitor to
discharge before further service.
(2) Remove the pinch welt from the front door
opening of the vehicle as needed to access the side
curtain airbag (Fig. 44).
(3) Remove the trim from the inside of the B-pillar.
(Refer to 23 - BODY/INTERIOR/B-PILLAR TRIM -
REMOVAL).
(4) Remove the grab handle from the headliner.
(Refer to 23 - BODY/INTERIOR/ASSIST HANDLE -
REMOVAL).
Fig. 44 Pinch Welt
1 - GRAB HANDLE
2 - B-PILLAR TRIM
3 - PINCH WELT
8O - 36 RESTRAINTSVA

INSTALLATION
(1) Position the MAF sensor to air cleaner housing
and install the retaining screws (Fig. 24).
(2) Connect the air intake hose to the MAF sensor
and tighten clamp.
(3) connect the MAF wiring harness connector.
(4) Connect negative battery cable.
O2 SENSOR
DESCRIPTION
The wide band oxygen sensor measures the oxygen
content in the exhaust gas to monitor EGR. The sen-
sor is mounted in the exhaust pipe at a 30 degree
angle to prevent the collection of moisture between
the sensor housing and element. The sensor is
located close to the turbocharger for a quicker
response time.
The oxygen sensor has five wires (heater power
and ground, reference voltage, and 2 wires for a
pump cell). The oxygen sensor connects to a six wire
harness connector. A non serviceable trimming resis-
tor is built into the sensor connector. The resistance
is dependent on the over all length and type of sen-
sor.
OPERATION
The O2 sensor is a planar zirconium dioxide (ZrO2)
dual cell limiting current probe with a integralheater. The term wide ban, refers to the ability of the
O2 sensor to generate a clear signal over a wide air-
fuel ratio measuring range. As a dual sensor, it incor-
porates a second O2 chamber (oxygen pump cell),
which requires a separate voltage supply.
The sensor element combines a sensor cell (8) and
an oxygen pump cell (9). Both cells are made of zir-
conium-dioxide (ZrO2) and are coated with porous
platinum electrodes. The sensor cell operates just
like a typical O2 sensor. The oxygen pump cell trans-
port oxygen ions when voltage is applied.
A gas sample chamber (5) is sandwiched between
the oxygen pump cell and the sensor cell. A pump
electrode and sensor cell electrode are located in the
sample chamber. A sample passage (10) connects the
sample chamber to the surrounding exhaust gas. A
sensor cell electrode is located in the reference air
channel (6), which connects to the outside air (Fig.
25).
Fig. 24 MANIFOLD AIR FLOW SENSOR
1 - WIRING HARNESS
2 - AIR INTAKE HOSE
3 - CLAMP
4 - MAF SENSOR
5 - AIR CLEANER HOUSING
VAFUEL INJECTION 14 - 45

(3) Install the Torxtsocket bolts (3) (Fig. 144) and
torque to 8 N´m (71 in.lbs.).
(4) Install a new oil filter (4) (Fig. 144).
(5) Install oil pan (5) (Fig. 144) and torque the oil
pan bolts to 8 N´m (71 in.lbs.).
(6) Install the oil drain plug (8) (Fig. 144) with a
new drain plug gasket (9). Torque the drain plug to
20 N´m (177 in.lbs.).
(7) Install the guide bushing (2) (Fig. 144) into the
transmission housing and install the bolt (11) to hold
the guide bushing in place.(8) Check O-ring on plug connector (1) (Fig. 145),
and replace if necessary.
(9) Install the plug connector (1) into the guide
bushing (2). Turn bayonet lock of guide bushing (2)
clockwise to connect plug connector (1).
(10) Position the heat shield (2) (Fig. 146) onto the
transmission housing and install the screw (1) and
bolt (3) to hold the shield in place.
(11) Fill the transmission with the correct oil
(Refer to LUBRICATION & MAINTENANCE/FLUID
TYPES - DESCRIPTION) using the standard proce-
dure (Refer to 21 - TRANSMISSION/AUTOMATIC -
NAG1/FLUID AND FILTER - STANDARD PROCE-
DURE - TRANSMISSION FILL).
Fig. 144 Install Electrohydraulic Unit
1 - HEAT SHIELD
2 - ELECTROHYDRAULIC UNIT
3 - BOLT
4 - OIL FILTER
5 - OIL PAN
6 - CLAMPING ELEMENT
7 - BOLT
8 - DRAIN PLUG
9 - DRAIN PLUG GASKET
10 - 13-PIN PLUG CONNECTOR
11 - BOLT
12 - GUIDE BUSHING
Fig. 145 Install Wiring Connector Plug
1 - PLUG CONNECTOR
2 - GUIDE BUSHING
Fig. 146 Install Heat Shield
1 - SCREW
2 - HEAT SHIELD
3 - BOLT
21 - 130 AUTOMATIC TRANSMISSION NAG1 - SERVICE INFORMATIONVA

To avoid overfilling transmission after a fluid
change or overhaul, perform the following procedure:
(1) Verify that the vehicle is parked on a level sur-
face.
(2) Remove locking pin (1) (Fig. 152). Remove the
plate of the locking pin with a suitable tool and press
out the pin remaining in the cap downwards.
(3) Remove cap (2).
(4) Add following initial quantity of required fluid
(Refer to LUBRICATION & MAINTENANCE/FLUID
TYPES - DESCRIPTION) to transmission:
(a) If only fluid and filter were changed, add7.4
L (14.8 pts.)of transmission fluid to transmission.
(b) If transmission was completely overhauled,
torque converter was replaced or drained, and
cooler was flushed, add7.7 L (16.3 pts.)of trans-
mission fluid to transmission.
(5) Check the transmission fluid (Refer to 21 -
TRANSMISSION/AUTOMATIC - NAG1/FLUID AND
FLUID - STANDARD PROCEDURE - CHECK OIL
LEVEL) and adjust as required.
FLUID / FILTER SERVICE
(1) Run the engine until the transmission oil
reaches operating temperature.
(2) Raise and support vehicle.
(3) Remove the torque converter drain plug access
plug from the bottom of the torque converter hous-
ing.
(4) Rotate the engine clockwise until the torque
converter drain plug (8) (Fig. 153) is aligned with the
access hole.
NOTE: Clean the area around the drain plug to pre-
vent dirt from entering the torque converter.
(5) Using a suitable drain pan to catch the fluid,
remove the torque converter drain plug (8) and allow
the torque converter to drain completely.
(6) Inspect the torque converter drain plug seal (9)
(Fig. 153). Replace the seal if necessary.
(7) Install the torque converter drain plug (8).
Tighten the drain plug to 14 N´m (10 ft.lbs.).
(8) Install the torque converter drain plug access
plug into the bottom of the torque converter housing.
(9) Using a suitable drain pan to catch the fluid,
remove the transmission oil pan drain plug (6) (Fig.
153) and allow the oil pan to drain completely.
(10) Inspect the transmission oil pan drain plug
seal (7). Replace the seal if necessary.
(11) Install the transmission oil pan drain plug (6).
Tighten the drain plug to 20 N´m (15 ft.lbs.).
(12) Remove the bolts (5) and retainers (4) (Fig.
153) holding the oil pan to the transmission.
(13) Remove the transmission oil pan (3) and gas-
ket (2) from the transmission.
Fig. 152 Remove Dipstick Tube Cap Lock
1 - LOCKING PIN
2 - TUBE CAP
3 - DIPSTICK TUBE
Fig. 153 Fluid/Filter Service Points
1 - OIL FILTER
2 - OIL PAN GASKET
3 - OIL PAN
4 - RETAINER
5 - BOLT
6 - OIL PAN DRAIN PLUG
7 - SEAL
8 - TORQUE CONVERTER DRAIN PLUG
9 - SEAL
21 - 134 AUTOMATIC TRANSMISSION NAG1 - SERVICE INFORMATIONVA