
SEAT BELT CHIME
The seat belt chime will sound for 4 to 8 seconds,
when the ignition is turned on and the driver's seat
belt is not buckled (seat belt switch is closed to
ground). This is a reminder to the driver to buckle
the seat belt. The seat belt lamp is controlled by the
mechanical instrument cluster. The cluster will also
illuminate the seat belt warning lamp for 6 seconds.
Buckling the driver's seat belt before the time out
has expired will cause the chime to stop immediately.
Chime rate: 38 to 62 chimes per minute.
To test the seat belt warning system, the ignition
switch must be in the OFF position for 1 minute
before starting the test. Turn the ignition switch to
the on position with the driver's seat belt not buck-
led. The seat belt warning lamp should light and the
chime should sound 4 to 8 seconds.
SEAT BELT LAMP
The seat belt lamp in the instrument cluster sig-
nals the vehicle passengers to fasten their seat belts.
The seat belt lamp is illuminated directly by the
instrument cluster for 6 seconds after the instrument
cluster receives the message from the Body Control
Module. The seat belt lamp is therefore illuminated
for 6 seconds whenever the ignition switch is moved
to run/start position.
(1) While ignition is off, the seat belt lamp will not
be illuminated.
(2) The ignition power feed status will be updated
every 250 milliseconds or on change.
(3) This lamp will be checked by the instrument
cluster for 6 seconds with every run/start cycle of the
ignition switch.
TURN SIGNAL ON CHIME
The turn signal on chime will warn the driver that
the turn signals have been left on. When the Body
Control Module receives a turn signal input for 1.6
km (1.0 miles), vehicle speed is greater than 24 km/h
(15 mph), the chime will sound continuously until the
turn signal is turned OFF. If vehicle speed drops
below 24 km/h (15 mph) prior to the warning being
activated, the accumulated distance traveled will be
reset. The turn signal chime is not activated whenthe emergency flashers are turned on. This feature
can also be disabled in EEPROM. Chime rate: 38 to
62 chimes per minute.
For the turn signal warning system to operate:
²Must have input from either the right or left
turn signal lamps. Creates a voltage change between
0 and battery voltage.
²The vehicle speed sensor sends a message to the
Powertrain Control Module that vehicle has exceeded
24 km/h (15 mph) for 1.6 km (1.0 miles).
²When the above two conditions are met, the
chime will sound. The chime will stop when no fur-
ther voltage change is detected.
²If hazard warning signals are pulsing, no chime
will sound.
²If speed drops below 24 km/h (15 mph) before
the warning is issued, the warning will not be issued
and the distance counter will be reset.
²If turn signal lamps are not working properly,
the chime will not sound.
²When using the scan tool, refer to the proper
Body Diagnostic Manual for the procedure.
WARNING LAMP ANNOUNCEMENT CHIME
The warning lamp announcement chime will warn
the driver to scan the instrument cluster to observe
which warning lamp is illuminated. Whenever the
volts, low fuel, low washer fluid, coolant level (gas/
diesel), low coolant level, engine temperature high
(diesel only), door ajar or gate ajar lamps are first
illuminated, the chime will sound one tone. The door/
liftgate ajar warning lamp announcement chime
sounds only if the vehicle speed is above 2 m.p.h.
Two seconds after ignition switch is turned ON or
until the seat belt warning chime ends, all warning
announcement chimes will be consolidated into one
warning announcement. This will occur 2 seconds
after the seat belt warning chime ends. If a warning
announcement should occur while another warning
chime in progress (turn signal, low oil pressure or
high speed warnings), no additional chimes will
sound after the chime in progress ends. All associ-
ated lamps will be illuminated, and the active chime
will be the warning announcement.
NS/GSCHIME WARNING/REMINDER SYSTEM 8U - 3
DIAGNOSIS AND TESTING (Continued)

²Stores transmitter data in permanent memory -
retraining is not required even if the battery dies or
is disconnected.
To operate, simply press the appropriate button on
the Universal Transmitter. The red LED will light up
while the signal is being transmitted.
NOTE: For security reasons, you are able to erase
the trained frequencies.
DIAGNOSIS AND TESTING
READING/DOME LAMP DIAGNOSIS
The dome lamps operate in conjunction with the
Remote Keyless Entry system. Refer to the Wiring
Diagrams group of this manual for component loca-
tions and circuit information. For additional diagnos-
tic information on lamp operation controlled by Body
Control Module (BCM) refer to the Body Diagnostic
Procedures Manual. For diagnosis of the reading
lamps and switches refer to (Fig. 3).
TRAVELER MESSAGES
Traveler data is obtained from the Body Control
Module (BCM) on the CCD bus wires. The CMTC
will not display information for any of the screens forwhich it did not receive the bus messages. The label
corresponding to the missing information will be lit.
If no traveler data is displayed, check the CCD com-
munications and the BCM. If the brightness level is
improper check the CCD bus. One general method
for checking the CCD bus communications between
CMTC and the BCM is refer to the following proce-
dure.
(1) STEP the CMTC to the Elapsed Time (ET).
(2) Press and release the reset button to reset the
module.
(3) If the elapsed time clock does not reset, or fails
to update, check the CCD wires and the BCM. The
DRB is recommended for checking the CCD and the
BCM.
(4) Perform the CMTC self diagnosis before replac-
ing the module.
UNIVERSAL TRANSMITTER
Before proceeding in diagnosis, check the transmit-
ter for battery voltage and a good ground at the
transmitter harness connector.
²The unit may not have been trained correctly,
try retraining the transmitter.
²The batteries in the hand-held transmitter may
be dead.
Fig. 3 Reading/Dome Lamp Diagnosis
NSOVERHEAD CONSOLE 8V - 3
DESCRIPTION AND OPERATION (Continued)

²Rotate your hand-held transmitter end-over-end
and train again. For best results, place the end oppo-
site from the battery compartment against the uni-
versal transmitter while training.
²The frequency of the hand-held transmitter may
not be in the desired frequencies between 286MHz
and 399MHz set by FCC.
SERVICE PROCEDURES
COMPASS CALIBRATION PROCEDURE
Variance is the difference between magnetic North
and geographic North (Fig. 4). To adjust the compass
variance set the CMTC to Compass/Temperature
mode and press RESET buttons for 5 seconds. The
symbol VAR and the current variance zone number
will be displayed. Press the STEP button to select
the proper variance zone as shown in (Fig. 4). Press
the US/Metric button to save the new variance zone
and normal CMTC operation. If both buttons are
held for 10 seconds instead 5 seconds the CMTC will
set variance to 8 and enter the fast calibration mode.
COMPASS CALIBRATION PROCEDURE (FAST
METHOD)
When the compass is subjected to excessive mag-
netic fields, the CMTC automatically enters a fast
calibration mode where is tries to compensate for the
large magnetic shifts.If the compass is inaccurate, appears to be inaccu-
rate and the CAL is not illuminated the fast calibra-
tion mode may be manually entered by using the
following procedure.
(1) Set the CMTC to Compass/Temperature mode
and press the reset button for 10 continuous seconds.
Manual activation of the fast calibration is generally
not required.
(2) Compass variance sets to the default of 8 after
the fast calibration is manually activated.
(3) Complete the compass variance setting proce-
dure by referring to the Compass Variance Procedure
in this section
(4) Drive the vehicle in three 360É turns in an area
free from large metal objects. If the CAL symbol
remains lit after completing this step, the roof panel
may need demagnetizing
DEMAGNETIZING PROCEDURE
A magnetic field can adversely affect the compass.
Magnetic interference can magnetize the roof panel.
Magnetizing can be caused by placing a permanent
magnet in contact with the roof panel. Example:
²Magnetic Base Antenna
²Magnetic screwdriver
²Audio speakers
²Refrigerator magnets.
²Pizza Signs
²Bubble gum flasher lights
Fig. 4 Variance Settings
8V - 4 OVERHEAD CONSOLENS
DIAGNOSIS AND TESTING (Continued)

kit 6680. Pull on the wire to remove the terminal
from the connector (Fig. 14) (Fig. 15).
(5) Reset the terminal locking tang, if it has one.
(6) Insert the removed wire in the same cavity on
the repair connector.
(7) Repeat steps four through six for each wire in
the connector, being sure that all wires are inserted
into the proper cavities. For additional connector pin-
out identification, refer to the wiring diagrams.
(8) Insert the connector locking wedge into the
repaired connector, if required.
(9)
Connect connector to its mating half/component.
(10) Connect battery and test all affected systems.
CONNECTOR AND TERMINAL REPLACEMENT
(1) Disconnect battery.
(2) Disconnect the connector (that is to be
repaired) from its mating half/component.
(3) Cut off the existing wire connector directly
behind the insulator. Remove six inches of tape from
the harness.
(4) Stagger cut all wires on the harness side at
1/2 inch intervals (Fig. 16).(5) Remove 1 inch of insulation from each wire on
the harness side.
(6) Stagger cut the matching wires on the repair
connector assembly in the opposite order as was done
on the harness side of the repair. Allow extra length
for soldered connections. Check that the overall
length is the same as the original (Fig. 16).
(7) Remove 1 inch of insulation from each wire.
(8) Place a piece of heat shrink tubing over one
side of the wire. Be sure the tubing will be long
enough to cover and seal the entire repair area.
(9) Spread the strands of the wire apart on each
part of the exposed wires.
(10) Push the two ends of wire together until the
strands of wire are close to the insulation.
(11) Twist the wires together.
(12) Solder the connection together using rosin
core type solder only.Do not use acid core solder.
(13) Center the heat shrink tubing over the joint
and heat using a heat gun. Heat the joint until the
tubing is tightly sealed and sealant comes out of both
ends of the tubing
(14) Repeat steps 8 through 13 for each wire.
(15) Re-tape the wire harness starting 1-1/2 inches
behind the connector and 2 inches past the repair.
(16) Re-connect the repaired connector.
(17) Connect the battery, and test all affected sys-
tems.
TERMINAL/CONNECTOR REPAIR- AUGAT
CONNECTORS
(1) Disconnect battery.
(2) Disconnect the connector from its mating half/
component.
(3) Push down on the yellow connector locking tab
to release the terminals (Fig. 17).
(4) Using special tool 6932, push the terminal to
remove it from the connector (Fig. 18).
Fig. 14 Terminal Removal
Fig. 15 Terminal Removal Using Special Tool
Fig. 16 Stagger Cutting Wires
8W - 01 - 12 8W-01 GENERAL INFORMATIONNS/GS
SERVICE PROCEDURES (Continued)

THROTTLE BODY....................... 64
THROTTLE POSITION SENSOR............ 65
UPSTREAM OXYGEN SENSOR............. 68
SPECIFICATIONS
TORQUE.............................. 72SPECIAL TOOLS
FUEL................................. 72
GENERAL INFORMATION
INTRODUCTION
All engines used in this section have a sequential
Multi-Port Electronic Fuel Injection system. The MPI
system is computer regulated and provides precise
air/fuel ratios for all driving conditions. The Power-
train Control Module (PCM) operates the fuel injec-
tion system.
The PCM regulates:
²Ignition timing
²Air/fuel ratio
²Emission control devices
²Cooling fan
²Charging system
²Idle speed
²Vehicle speed control
Various sensors provide the inputs necessary for
the PCM to correctly operate these systems. In addi-
tion to the sensors, various switches also provide
inputs to the PCM.
All inputs to the PCM are converted into signals.
The PCM can adapt its programming to meet chang-
ing operating conditions.
Fuel is injected into the intake port above the
intake valve in precise metered amounts through
electrically operated injectors. The PCM fires the
injectors in a specific sequence. Under most operat-
ing conditions, the PCM maintains an air fuel ratio
of 14.7 parts air to 1 part fuel by constantly adjust-
ing injector pulse width. Injector pulse width is the
length of time the injector is open.
The PCM adjusts injector pulse width by opening
and closing the ground path to the injector. Engine
RPM (speed) and manifold absolute pressure (air
density) are the primary inputs that determine injec-
tor pulse width.
MODES OF OPERATION
As input signals to the PCM change, the PCM
adjusts its response to output devices. For example,
the PCM must calculate a different injector pulse
width and ignition timing for idle than it does for
Wide Open Throttle (WOT). There are several differ-
ent modes of operation that determine how the PCM
responds to the various input signals.
There are two different areas of operation, OPEN
LOOP and CLOSED LOOP.
During OPEN LOOP modes the PCM receives
input signals and responds according to preset PCMprogramming. Input from the oxygen (O2S) sensor is
not monitored during OPEN LOOP modes.
During CLOSED LOOP modes the PCM does mon-
itor the O2S sensor input. This input indicates to the
PCM whether or not the calculated injector pulse
width results in the ideal air/fuel ratio of 14.7 parts
air to 1 part fuel. By monitoring the exhaust oxygen
content through the O2S sensor, the PCM can fine
tune the injector pulse width. Fine tuning injector
pulse width allows the PCM to achieve optimum fuel
economy combined with low emissions.
The multi-port fuel injection system has the follow-
ing modes of operation:
²Ignition switch ON (zero RPM)
²Engine start-up
²Engine warm-up
²Cruise (Idle)
²Acceleration
²Deceleration
²Wide Open Throttle
²Ignition switch OFF
The engine start-up (crank), engine warm-up, and
wide open throttle modes are OPEN LOOP modes.
Under most operating conditions, the acceleration,
deceleration, and cruise modes,with the engine at
operating temperatureare CLOSED LOOP modes.
IGNITION SWITCH ON (ZERO RPM) MODE
When the multi-port fuel injection system is acti-
vated by the ignition switch, the following actions
occur:
²The PCM determines atmospheric air pressure
from the MAP sensor input to determine basic fuel
strategy.
²The PCM monitors the coolant temperature sen-
sor and throttle position sensor input. The PCM mod-
ifies fuel strategy based on this input.
When the key is in the ON position and the engine
is not running (zero rpm), the Automatic Shutdown
(ASD) relay and fuel pump relay are not energized.
Therefore battery voltage is not supplied to the fuel
pump, ignition coil, fuel injectors or oxygen sensor
heating element.
ENGINE START-UP MODE
This is an OPEN LOOP mode. The following
actions occur when the starter motor is engaged.
If the PCM receives the camshaft position sensor
and crankshaft position sensor signals, it energizes
the ASD relay and fuel pump relay. These relays sup-
ply battery voltage to the fuel pump, fuel injectors,
14 - 30 FUEL SYSTEMNS
SPECIFICATIONS (Continued)

For periodic draining of water from the bowl, refer
to Fuel Filter/Water Separator Removal/Installation
in this group.
FUEL SHUTDOWN SOLENOID
The fuel shutdown solenoid is controlled and
operated by the PCM.
The fuel shutdown (shut-off) solenoid is used to
electrically shut off the diesel fuel supply to the high-
pressure fuel injection pump. The solenoid is
mounted to the rear of the injection pump (Fig. 4).
The solenoid controls starting and stopping of the
engine regardless of the position of the accelerator
pedal. When the ignition (key) switch is OFF, the
solenoid is shut off and fuel flow is not allowed to the
fuel injection pump. When the key is placed in the
ON or START positions, fuel supply is allowed at the
injection pump.
FUEL INJECTION PUMP
The fuel injection pump is a mechanical distribu-
tor±type, Bosch VP36 series (Fig. 5). A gear on the
end of the injection pump shaft meshes with the
drive gear at the front of engine. The pump is
mechanically timed, relative to the position of the
cam and crankshaft. The PCM can make adjust-
ments to the timing of the injection pump.
The injection pump contains the fuel shutdown
solenoid, fuel temperature sensor, control sleeve sen-
sor, fuel quantity actuator and the fuel timing sole-
noid (Fig. 5).In the electronically controlled injection pump, the
pump plunger works the same as the pump plunger
in a mechanically controlled injection pump, but the
amount of fuel and the time the fuel is injected is
controlled by the vehicle's PCM, instead of by a
mechanical governor assembly. A solenoid controlled
by the PCM is used in place of the mechanical gov-
ernor assembly, and it moves a control sleeve inside
the pump that regulates the amount of fuel being
injected. There is no mechanical connection between
the accelerator pedal and the electronically controlled
injection pump. Instead, a sensor connected to the
accelerator pedal sends a signal to the PCM that rep-
resents the actual position of the accelerator pedal.
The PCM uses this input, along with input from
other sensors to move the control sleeve to deliver
the appropriate amount of fuel. This system is known
as ªDrive-By-Wireº
The actual time that the fuel is delivered is very
important to the diesel combustion process. The PCM
monitors outputs from the engine speed sensor (fly-
wheel position in degrees), and the fuel injector sen-
sor (mechanical movement within the #1 cylinder
fuel injector). Outputs from the Accelerator Pedal
Position sensor, engine speed sensor (engine rpm)
and engine coolant temperature sensor are also used.
The PCM will then compare its set values to these
outputs to electrically adjust the amount of fuel tim-
ing (amount of advance) within the injection pump.
This is referred to as ªClosed Loopº operation. The
PCM monitors fuel timing by comparing its set value
to when the injector #1 opens. If the value is greater
than a preset value a fault will be set.
Fig. 4 Fuel Shutdown Solenoid and Overflow Valve
Location
Fig. 5 Fuel Injection Pump
NS/GSFUEL SYSTEMÐ2.5L DIESEL ENGINE/2.0L GAS ENGINE 14 - 5
DESCRIPTION AND OPERATION (Continued)

Actual electric fuel timing (amount of advance) is
accomplished by the fuel timing solenoid mounted to
the bottom of the injection pump (Fig. 5). Fuel timing
will be adjusted by the PCM, which controls the fuel
timing solenoid.
An overflow valve is attached into the fuel return
line at the rear of the fuel injection pump (Fig. 4).
This valve serves two purposes. One is to ensure that
a certain amount of residual pressure is maintained
within the pump when the engine is switched off.
This will prevent the fuel timing mechanism within
the injection pump from returning to its zero posi-
tion. The other purpose is to allow excess fuel to be
returned to the fuel tank through the fuel return
line. The pressure values within this valve are preset
and can not be adjusted.
The fuel injection pump supplies high±pressure
fuel of approximately 45,000 kPa (6526 psi) to each
injector in precise metered amounts at the correct
time.
For mechanical injection pump timing, refer to
Fuel Injection Pump Timing in the Service Proce-
dures section of this group.
FUEL INJECTORS
Fuel drain tubes (Fig. 6) are used to route excess
fuel back to the overflow valve (Fig. 4) at the rear of
the injection pump. This excess fuel is then returned
to the fuel tank through the fuel return line.
The injectors are connected to the fuel injection
pump by the high± pressure fuel lines. A separate
injector is used for each of the four cylinders. An
injector containing a sensor (Fig. 7) is used on thecylinder number one injector. This injector is called
instrumented injector #1 or needle movement sensor.
It is used to tell the PCM when the #1 injector's
internal spring-loaded valve seat has been forced
open by pressurized fuel being delivered to the cylin-
der, which is at the end of its compression stroke.
When the instrumented injector's valve seat is force
open, it sends a small voltage spike pulse to the
PCM. This tells the PCM that the engine is at TDC
on the number one cylinder. It is not used with the
other three injectors.
Fuel enters the injector at the fuel inlet (top of
injector) and is routed to the needle valve bore. When
fuel pressure rises to approximately 15,000±15,800
kPa (2175±2291 psi), the needle valve spring tension
is overcome. The needle valve rises and fuel flows
through the spray holes in the nozzle tip into the
combustion chamber. The pressure required to lift
the needle valve is the injector opening pressure set-
ting. This is referred to as the ªpop-offº pressure set-
ting.
Fuel pressure in the injector circuit decreases after
injection. The injector needle valve is immediately
closed by the needle valve spring and fuel flow into
the combustion chamber is stopped. Exhaust gases
are prevented from entering the injector nozzle by
the needle valve.
A copper washer (gasket) is used at the base of
each injector (Fig. 7) to prevent combustion gases
from escaping.
Fuel injector firing sequence is 1±3±4±2.
FUEL TUBES/LINES/HOSES AND CLAMPSÐLOW-
PRESSURE TYPE
Also refer to the proceeding section on Quick±Con-
nect Fittings.
Inspect all hose connections such as clamps, cou-
plings and fittings to make sure they are secure andFig. 6 Fuel Injectors and Drain Tubes
Fig. 7 Fuel Injector Sensor
14 - 6 FUEL SYSTEMÐ2.5L DIESEL ENGINE/2.0L GAS ENGINENS/GS
DESCRIPTION AND OPERATION (Continued)

leaks are not present. The component should be
replaced immediately if there is any evidence of deg-
radation that could result in failure.
Never attempt to repair a plastic fuel line/tube or a
quick±connect fitting. Replace complete line/tube as
necessary.
Avoid contact of any fuel tubes/hoses with other
vehicle components that could cause abrasions or
scuffing. Be sure that the fuel lines/tubes are prop-
erly routed to prevent pinching and to avoid heat
sources.
The lines/tubes/hoses are of a special construction.
If it is necessary to replace these lines/tubes/hoses,
use only original equipment type.
The hose clamps used to secure the rubber hoses
are of a special rolled edge construction. This con-
struction is used to prevent the edge of the clamp
from cutting into the hose. Only these rolled edge
type clamps may be used in this system. All other
types of clamps may cut into the hoses and cause
fuel leaks.
Where a rubber hose is joined to a metal tube
(staked), do not attempt to repair. Replace entire
line/tube assembly.
Use new original equipment type hose clamps.
Tighten hose clamps to 2 N´m (20 in. lbs.) torque.
QUICK-CONNECT FITTINGSÐLOW PRESSURE
TYPE
Different types of quick-connect fittings are used to
attach various fuel system components. These are: a
single-tab type, a two-tab type or a plastic retainer
ring type (Fig. 8). Refer to Quick-Connect Fittings in
the Removal/Installation section for more informa-
tion.
CAUTION: The interior components (o-rings, spac-
ers) of quick-connect fitting are not serviced sepa-
rately, but new pull tabs are available for some
types. Do not attempt to repair damaged fittings or
fuel lines/tubes. If repair is necessary, replace the
complete fuel tube assembly.
HIGH-PRESSURE FUEL LINES
CAUTION: The high±pressure fuel lines must be
held securely in place in their holders. The lines
cannot contact each other or other components. Do
not attempt to weld high±pressure fuel lines or to
repair lines that are damaged. Only use the recom-
mended lines when replacement of high±pressure
fuel line is necessary.
High±pressure fuel lines deliver fuel under pres-
sure of up to approximately 45,000 kPa (6526 PSI)
from the injection pump to the fuel injectors. Thelines expand and contract from the high±pressure
fuel pulses generated during the injection process. All
high±pressure fuel lines are of the same length and
inside diameter. Correct high±pressure fuel line
usage and installation is critical to smooth engine
operation.
WARNING: USE EXTREME CAUTION WHEN
INSPECTING FOR HIGH±PRESSURE FUEL LEAKS.
INSPECT FOR HIGH±PRESSURE FUEL LEAKS WITH
A SHEET OF CARDBOARD. HIGH FUEL INJECTION
PRESSURE CAN CAUSE PERSONAL INJURY IF
CONTACT IS MADE WITH THE SKIN.
FUEL DRAIN TUBES
These rubber tubes are low±pressure type.
Some excess fuel is continually vented from the
fuel injection pump. During injection, a small amount
of fuel flows past the injector nozzle and is not
injected into the combustion chamber. This fuel
drains into the fuel drain tubes (Fig. 9) and back to
the tee banjo fitting, which is connected to the same
line as the overflow valve, which allows a variable
quantity to return to the fuel tank. The overflow
valve is calibrated to open at a preset pressure.
Excess fuel not required by the pump to maintain the
minimum pump cavity pressure is then returned
through the overflow valve and on to the fuel tank
through the fuel return line.
Fig. 8 Plastic Retainer Ring-Type Fitting
NS/GSFUEL SYSTEMÐ2.5L DIESEL ENGINE/2.0L GAS ENGINE 14 - 7
DESCRIPTION AND OPERATION (Continued)