2004 CHRYSLER VOYAGER key

INSTALLATION
(1) Place hood in position on vehicle. With assis-
tance from a helper at the opposite side of the vehicle
to support the hood, install bottom bolts attaching
hood to hinge finger tight.
(2) Install top bolts attaching hood to hinge finger
tight.
(3) Position bolts at marks and tighten. Tighten
bolts to 13.5 N´m (120 in. lbs.) torque. The hood
should be aligned to 4 mm (0.160 in.) gap to the front
fenders and flush across the top surfaces along fend-
ers.
(4) Verify hood operation and alignment.
LATCH
REMOVAL
(1) Release hood latch and open hood.
(2) Remove bolts attaching hood latch to radiator
closure panel crossmember (Fig. 3).
(3) Remove hood latch from crossmember.
(4) Disconnect hood release cable from hood latch
(Fig. 4).
(5) Remove hood latch from vehicle.
INSTALLATION
(1) Position hood latch on vehicle.
(2) Connect hood release cable from hood latch.
(3) Position hood latch on crossmember.
(4) Align hood latch by placing latch over net
pierced tabs. If alignment is required, flatten or
grind tabs.
(5) Verify hood operation and alignment. Adjust as
necessary.(6) Tighten attaching bolts to 13.5 N´m (10 ft. lbs.)
torque.
LATCH RELEASE CABLE
REMOVAL
(1) Remove hood latch.
(2) Disengage cable end from hood latch locking
mechanism.
(3) Slide cable case end sideways in keyhole slot of
hood latch while pinching barb on cable case closed.
(4) Remove cable from latch (Fig. 4).
(5) Remove hood release handle from instrument
panel.
(6) Disengage rubber grommet cable insulator
from hole in dash panel.
(7) Attach a suitable length of mechanic's wire to
latch end of cable to assist cable installation.
Fig. 2 HOOD
1 - HOOD
2 - HOOD LATCH STRIKER
3 - HOOD HALF OF HOOD HINGE
Fig. 3 HOOD LATCH
1 - HOOD RELEASE CABLE
2 - HOOD LATCH
3 - RADIATOR CLOSURE PANEL CROSSMEMBER
Fig. 4 HOOD
1 - RELEASE CABLE CASE
2 - HOOD LATCH
3 - RELEASE CABLE END
RSHOOD23-61
HOOD (Continued)

(8) Route cable back from latch through engine
compartment toward dash panel near power brake
booster (Fig. 5).
(9) Remove attaching clips from cable case.
(10) From inside vehicle, pull cable through dash
panel until mechanic's wire is exposed.
(11) Disconnect cable from mechanic's wire.
(12) Remove hood release cable from vehicle.
INSTALLATION
(1) Place hood release cable in position under
instrument panel.
(2) Attach latch end of hood release cable to
mechanic's wire protruding through dash panel.
(3) Route cable forward through engine compart-
ment toward latch by pulling on mechanic's wire
(Fig. 5).(4) Disconnect mechanic's wire from cable.
(5) Engage rubber grommet cable insulator into
hole in dash panel.
(6) Install hood release handle into instrument
panel.
(7) Place cable in position on latch.
(8) Slide cable case end sideways into keyhole slot
of hood latch.
(9) Engage cable end into hood latch locking mech-
anism.
(10) Install hood latch.
(11) Install attaching clips to cable case and install
clips into original holes in strut tower, fender, head-
lamp area, and radiator closure panel crossmember.
LATCH STRIKER
REMOVAL
(1) Release hood latch and open hood.
(2) Remove bolts attaching striker to inside of
hood.
(3) Remove hood latch striker from vehicle.
INSTALLATION
(1) Position hood latch striker on vehicle.
(2) Install bolts attaching hood latch striker to
hood.
(3) Align hood latch striker to engage smoothly
into hood latch.
(4) Verify hood operation and alignment. Adjust as
necessary.
(5) Tighten attaching bolts to 13.5 N´m (10 ft. lbs.)
torque.Fig. 5 HOOD RELEASE CABLE ROUTING
1 - GROMMET
2 - HOOD RELEASE CABLE
3 - RADIATOR CLOSURE PANEL CROSSMEMBER
23 - 62 HOODRS
LATCH RELEASE CABLE (Continued)

SUNROOF
TABLE OF CONTENTS
page page
SUNROOF
DESCRIPTION........................116
DIAGNOSIS AND TESTING - SUNROOF.....116
DRAIN TUBE
REMOVAL............................119
INSTALLATION........................120
GLASS PANEL
REMOVAL............................120
INSTALLATION........................120
ADJUSTMENTS
SUNROOF GLASS PANEL ADJUSTMENT . . 120
SUNROOF ASSEMBLY
REMOVAL............................120
INSTALLATION........................120
SUNSHADE
REMOVAL............................120INSTALLATION........................121
WIND DEFLECTOR
REMOVAL............................121
INSTALLATION........................121
WATER CHANNEL
REMOVAL............................121
INSTALLATION........................121
SUNROOF MOTOR
REMOVAL............................121
INSTALLATION........................121
ADJUSTMENTS
ADJUSTMENT.......................122
SUNROOF SWITCH
REMOVAL............................123
INSTALLATION........................123
SUNROOF
DESCRIPTION
WARNING: Keep fingers and other body parts out
of sunroof opening at all times.
The sun roof features consists of: (Fig. 1)
²Sun roof glass
²Sun roof sun shade
The sunroof power sliding glass panel and sun-
shade can be positioned anywhere along its travel,
rearward of glass panel front edge.
The sunroof is electrically operated from a switch
located in the overhead console. To operate the sun-
roof the ignition switch must be in the Accessory or
On/Run position. Both switchs are a rocker style
design that open or close the sunroof. When pressing
and releasing the open button once, the sunroof will
express open to the comfort stop and the wind deflec-
tor will raise. If the button is pressed a second time,
the sunroof will continue to open to full travel unless
the button is released, at which time it will stop in
that position. Pressing and holding the close button
will close the sunroof. If the close button is released
before the glass fully closes, the sunroof will stop in
that position. The vent switch operates in a similar
manor. The sunroof will also operate for up to fifteenminutes after the ignition key is turned off for cus-
tomer comfort and convenance while parking.
DIAGNOSIS AND TESTING - SUNROOF
Refer to Sunroof Diagnostic Chart for possible
causes. Before beginning sunroof diagnostics verify
that all other power accessories are in proper operat-
ing condition. If not, a common electrical problem
may exist. Refer to Wiring Diagrams, in this publica-
tion for circuit, splice and component descriptions.
Check the condition of the circuit protection (20 amp
circuit breaker in the Junction Block). Inspect all
wiring connector pins for proper engagement and
continuity. Check for battery voltage at the power
sunroof controller, refer to Wiring Diagrams, for cir-
cuit information. If battery voltage of more than 10
volts is detected at the controller, proceed with the
following tests (the controller will not operate at less
than 10 volts).
Before beginning diagnosis for wind noise or water
leaks, verify that the problem was not caused by
releasing the control switch before the sunroof was
fully closed. The sunroof module has a water-man-
agement system. If however, the sunroof glass is in a
partial closed position, high pressure water may be
forced beyond the water management system bound-
aries and onto the headlining.
23 - 116 SUNROOFRS

OPERATION - DUAL ZONE
²The two slide controls enable continuously vari-
able proportioning of the conditioned air.
²The mode control knob enables continuously
variable proportioning of air flow between modes and
has detents adjacent to each icon.
²The blower control provides four separate speeds
and an Off position.
²When the heater-A/C system is off, the HVAC
computer closes the recirculation door to prevent out-
side air from entering the passenger compartment.
²Interior air may be recirculated to speed up
heating or cooling in all modes except defrost and
mix by pressing the Recirculate button on the A/C-
heater control.
²To reduce humidity for rapid defogging, the A/C
compressor runs automatically in modes from ªmixº
to full defrost when outside temperatures are above
freezing.
²Air conditioning is available in any mode by
pressing the snowflake, A/C on/off button.
OPERATION - MANUAL THREE ZONE
FRONT CONTROL PANEL
²Primary control of the rear heater-A/C system is
on the instrument panel. This control allows the
driver to set the rear compartment fan speed, to turn
the rear heater-A/C system off, or to give control to
the intermediate seat occupants by switching to the
Rear position. When the rear heater-A/C system is
controlled from the instrument panel, rear air tem-
perature is based on the driver-side temperature con-
trol position, and the mode (floor or overhead air) is
based on the front control's mode position.
²The mode control knob enables continuously
variable proportioning of air flow between modes but
has detents adjacent to each icon.
²The blower control provides four separate speeds
and an Off position. When the heater-A/C system is
off, the HVAC computer closes the recirculation door
to prevent outside air from entering the passenger
compartment.
²Interior air may be recirculated to speed up
heating or cooling in all modes except defrost and
mix by pressing the Recirculate button on the control
panel.
²To reduce humidity for rapid defogging the A/C
compressor runs automatically in modes from ªmix'
to full defrost when outside temperatures are above
freezing.
²Air conditioning is available in any mode by
pressing the snowflake, A/C on/off, button.
REAR CONTROL PANEL
With the rear control active, temperature selection
dictates the air distribution mode (floor or overhead
air) of the rear unit: a cool temperature setting
directs flow to the overhead outlets and a warm tem-
perature setting to the floor.
OPERATION - THREE ZONE ATC
Comfort temperature or perceived temperature is
affected by air flow, sun levels on exposed skin, etc. The
air temperature may be higher or lower than the com-
fort temperature. Two infrared sensors in the instru-
ment panel center stack measure the temperature of
the occupants to determine their comfort level relative
to the selected comfort temperature. The integral
HVAC computer adjusts temperature and air flow rates
to maintain the customer-perceived comfort tempera-
ture. The air temperature in the passenger compart-
ment may be slightly higher or lower than the comfort
temperature at any time. For instance, on sunny sum-
mer days the air flow will probably be cooler than the
comfort temperature; on cold or cloudy days and at
night it will probably be slightly warmer. Infrared
Three-Zone Temperature Control provides side-to-side
and front-to-rear variations in comfort temperature set-
tings. The Infrared Three-Zone Automatic Temperature
Control fan provides a continuously variable air flow
rate to meet occupant comfort requirements.
FRONT CONTROL PANEL
²AUTO HI/LO± This system features two sets of
automatic control logic that allow either a rapid cool-
down rate or a somewhat slower cool-down rate with
less fan noise. HI-AUTO controls the system to reach
its assigned temperature quickly with a higher fan
speed. LO-AUTO controls the system to reach its
assigned temperature somewhat slower with less fan
noise. Both modes will automatically engage auto
recirculation.
²DE-FROST± The defrost function is active
when the rear window defogger function is active or
when the defog/defrost mode is selected.
²RECIRC± The RECIRC button will close the
air inlet door. If the system is in auto recirc (indica-
tor being displayed automatically), pressing the man-
ual recirc button will disable the auto recirc function
until one of the auto keys are pressed or the ignition
is cycled. If Auto HI/LO is pressed while manual
recirc is active, manual recirc will be deactivated.
²REAR WINDOW DEFOGGER± Pushing the
button sends a PCI bus message to the Intelligent
Power Module which controls the Rear Window
Defogger and side view mirror (if equipped) circuitry.
The defogger function will be active for 10 minutes
and can be turned off by a switch press. The defogger
will function while the control is in the ON mode.
RSHEATING & AIR CONDITIONING24-5
HEATING & AIR CONDITIONING (Continued)

A/C COMPRESSOR CLUTCH/
COIL
DESCRIPTION
The A/C compressor clutch assembly consists of a
stationary electromagnetic A/C clutch field coil with a
zener diode, a pulley bearing and pulley assembly,
and a clutch plate (Fig. 1). A/C clutch field coil and
the pulley bearing and pulley assembly are each
retained on the nose of the compressor front housing
with snap rings. The clutch plate is keyed or splined
to the compressor shaft, and secured with a nut or
bolt (depending on application). These components
provide the means to engage and disengage the com-
pressor from the engine serpentine accessory drive
belt.
The A/C compressor clutch and coil are available
for separate service replacement. The clutch coil
zener diode is integral to the clutch coil pigtail wire
and connector and, if faulty or damaged, the clutch
electromagnetic coil must be replaced.
OPERATION
The compressor clutch components provide the
means to engage and disengage the compressor from
the engine serpentine accessory drive belt. When the
clutch coil is energized, it magnetically draws the
clutch plate into contact with the clutch pulley and
drives the compressor shaft. When the coil is not
energized, the pulley freewheels on the clutch hub
bearing, which is part of the pulley.
A zener diode is connected in parallel with the
clutch electromagnetic coil. This diode controls the
dissipation of voltage induced into the coil windingsby the collapsing of the electromagnetic fields that
occurs when the compressor clutch is disengaged.
The zener diode dissipates this induced voltage by
regulating a current path to ground. This arrange-
ment serves to protect other circuits and components
from potentially damaging voltage spikes in the vehi-
cle electrical system that might occur if the voltage
induced in the clutch coil windings could not be dis-
sipated.
The compressor clutch engagement is controlled by
several components: the heater-A/C controls in the
passenger compartment, the A/C pressure transducer
on the liquid line, the evaporator temperature sensor
on the expansion valve for automatic temperature
control (ATC) system or on the HVAC housing for
manual temperature control (MTC) system, the Pow-
ertrain Control Module (PCM) in the engine compart-
ment, and the compressor clutch relay in the
Integrated Power Module (IPM). The PCM may delay
compressor clutch engagement for up to thirty sec-
onds (Refer to 8 - ELECTRICAL/ELECTRONIC
CONTROL MODULES/POWERTRAIN CONTROL
MODULE - DESCRIPTION - PCM OPERATION).
DIAGNOSIS AND TESTING - A/C COMPRESSOR
CLUTCH COIL
The air conditioning compressor clutch coil electri-
cal circuit is controlled by the powertrain control
module (PCM) through the A/C compressor clutch
relay, which is located in the integrated power mod-
ule (IPM) in the engine compartment. Begin testing
of a suspected compressor clutch coil problem by per-
forming the preliminary checks.
PRELIMINARY CHECKS
(1) If the compressor clutch will not engage, verify
the refrigerant charge level (Refer to 24 - HEATING
& AIR CONDITIONING/PLUMBING - FRONT/RE-
FRIGERANT - DIAGNOSIS AND TESTING -
REFRIGERANT CHARGE LEVEL). If the refriger-
ant charge level is OK, go to Step 2. If the refriger-
ant charge level is not OK, adjust the refrigerant
charge as required.
(2) If the A/C compressor clutch still will not
engage, disconnect the wire harness connector for the
A/C pressure transducer and check for battery cur-
rent at the connector with the engine running and
the A/C-heater control set to the A/C mode. If OK, go
to TESTS. If not OK, refer to Body Diagnostic Proce-
dures to perform further diagnosis.
TESTS
(1) Verify the battery state of charge (Refer to 8 -
ELECTRICAL/BATTERY SYSTEM/BATTERY -
DIAGNOSIS AND TESTING).
Fig. 1 Compressor Clutch - Typical
1 - CLUTCH PLATE
2 - SHAFT KEY (SOME MODELS)
3 - PULLEY AND BEARING
4 - CLUTCH COIL
5 - CLUTCH SHIMS
6 - SNAP RING
7 - SNAP RING
RSCONTROLS - FRONT24-15

INSTALLATION
WARNING: DO NOT OPERATE THE DIESEL SUP-
PLEMENTAL CABIN HEATER IN AN ENCLOSED
AREA SUCH AS A GARAGE THAT DOES NOT HAVE
EXHAUST VENTILATION FACILITIES. ALWAYS VENT
THE CABIN HEATER EXHAUST WHEN OPERATING
THE CABIN HEATER. ALLOW THE DIESEL SUPPLE-
MENTAL CABIN HEATER TO COOL BEFORE PER-
FORMING ANY SERVICE PROCEDURES TO THE
CABIN HEATER. VERIFY THAT ALL DIESEL SUP-
PLEMENTAL CABIN HEATER FUEL LINES ARE
SECURELY FASTENED TO THEIR RESPECTIVE
COMPONENTS BEFORE PERFORMING ANY SER-
VICE PROCEDURES TO THE CABIN HEATER. FAIL-
URE TO FOLLOW THESE INSTRUCTION MAY
RESULT IN PERSONAL INJURY OR DEATH.
NOTE: Verify that there is more than 1/8 of a tank of
fuel in the vehicle's fuel tank before performing this
procedure. Add fuel, if necessary.
(1) Install the cabin heater fuel supply line into
vehicle and fuel line retainers.
(2) Install the fuel line connection at the fuel tank
and tighten the connection securely.
(3) Install the fuel line at the dosing pump and
tighten the connection securely.
(4) Lower the vehicle.
NOTE: Failure to prime the dosing pump after drain-
ing the supplemental cabin fuel line will prevent
cabin heater activation during the first attempt to
start the cabin heater. This will also set a diagnostic
trouble code (DTC) in the cabin heater control's
memory. Do not perform the Dosing Pump Priming
procedure if an attempt was made to start the cabin
heater without priming the dosing pump first. This
will put excess fuel in the cabin heater and cause
smoke to emit from the cabin heater exhaust pipe
when cabin heater activation occurs.
(5) Connect the DRBIIItscan tool to the diagnos-
tic link connector.
(6) Turn the ignition to the ON position.
NOTE: Do not activate the dosing pump prime more
than one time. This will put excess fuel in the sup-
plemental cabin heater and cause smoke to emit
from the cabin heater exhaust pipe when cabin
heater activation occurs.
NOTE: A clicking noise heard coming from the dos-
ing pump indicates that the pump is operational.(7) With the DRBIIItscan tool in Cabin Heater,
select System Tests and Dosing Pump Prime. Allow
the dosing pump to run for the full 45 second cycle
time. When the 45 second cycle is complete, press
Page Back on the DRBIIItscan tool key pad to exit
the Dosing Pump Prime. The Dosing Pump Priming
procedure is now complete.
HEATER UNIT
REMOVAL
WARNING: DO NOT OPERATE THE DIESEL SUP-
PLEMENTAL CABIN HEATER IN AN ENCLOSED
AREA SUCH AS A GARAGE THAT DOES NOT HAVE
EXHAUST VENTILATION FACILITIES. ALWAYS VENT
THE CABIN HEATER EXHAUST WHEN OPERATING
THE CABIN HEATER. ALLOW THE DIESEL SUPPLE-
MENTAL CABIN HEATER TO COOL BEFORE PER-
FORMING ANY SERVICE PROCEDURES TO THE
CABIN HEATER. VERIFY THAT ALL DIESEL SUP-
PLEMENTAL CABIN HEATER FUEL LINES ARE
SECURELY FASTENED TO THEIR RESPECTIVE
COMPONENTS BEFORE PERFORMING ANY SER-
VICE PROCEDURES TO THE CABIN HEATER. FAIL-
URE TO FOLLOW THESE INSTRUCTION MAY
RESULT IN PERSONAL INJURY OR DEATH.
(1) Raise and support the vehicle. Take note of the
location of the flexible section of the cabin heater
exhaust tube.
(2) Drain the engine cooling system (Refer to 7 -
COOLING - STANDARD PROCEDURE).
(3) Carefully open one hose to the underbody tube
assembly and drain the remaining coolant. A salvage
hose is a good idea to control the residual coolant, as
flow will occur from both the cabin heater and the
hose and tube assemblies.
(4) Remove the second hose from the underbody
hose and tube assembly.
(5) Loosen the hose and tube assembly from the
toe-board crossmember at two locations.
(6) Disconnect the electrical connector from the
body harness near the toe-board crossmember and
rail.
(7) Remove the wiring harness from the toe-board
crossmember (Refer to 24 - HEATING & AIR CON-
DITIONING/CABIN HEATER/HEATER UNIT -
REMOVAL).
(8) Open the fuel filler cap. Disconnect the rubber
fuel hose between the body tube assembly and the
fuel pump nipple at the body tube joint. A minimal
amount of fuel may flow from the open port.
NOTE: Utilize an approved fuel storage container to
catch any residual fuel.
24 - 118 CABIN HEATERRS
FUEL LINE (Continued)

OPERATIONÐThe Oxygen Sensor Heater Moni-
tor begins after the ignition has been turned OFF.
The PCM sends a 5 volt bias to the oxygen sensor
every 1.6 seconds. The PCM keeps it biased for 35
ms each time. As the sensor cools down, the resis-
tance increases and the PCM reads the increase in
voltage. Once voltage has increased to a predeter-
mined amount, higher than when the test started,
the oxygen sensor is cool enough to test heater oper-
ation.
When the oxygen sensor is cool enough, the PCM
energizes the ASD relay. Voltage to the O2 sensor
begins to increase the temperature. As the sensor
temperature increases, the internal resistance
decreases. The PCM continues biasing the 5 volt sig-
nal to the sensor. Each time the signal is biased, the
PCM reads a voltage decrease. When the PCM
detects a voltage decrease of a predetermined value
for several biased pulses, the test passes.
The heater elements are tested each time the
engine is turned OFF if all the enabling conditions
are met. If the monitor fails, the PCM stores a
maturing fault and a Freeze Frame is entered. If two
consecutive tests fail, a DTC is stored. Because the
ignition is OFF, the MIL is illuminated at the begin-
ning of the next key cycle.
Enabling ConditionsÐThe following conditions
must be met for the PCM to run the oxygen sensor
heater test:
²Engine run time of at least 3 minutes
²Engine run time at a predetermined speed
and throttle opening.
²Key OFF power down
²Battery voltage of at least 10 volts
²Sufficient Oxygen Sensor cool down
Pending ConditionsÐThere are not conditions or
situations that prompt conflict or suspension of test-
ing. The oxygen sensor heater test is not run pending
resolution of MIL illumination due to oxygen sensor
failure.
SuspendÐThere are no conditions which exist for
suspending the Heater Monitor.
CATALYST MONITOR
To comply with clean air regulations, vehicles are
equipped with catalytic converters. These converters
reduce the emission of hydrocarbons, oxides of nitro-
gen and carbon monoxide.
Normal vehicle miles or engine misfire can cause a
catalyst to decay. A meltdown of the ceramic core can
cause a reduction of the exhaust passage. This can
increase vehicle emissions and deteriorate engine
performance, driveability and fuel economy.
The catalyst monitor uses dual oxygen sensors
(O2S's) to monitor the efficiency of the converter. The
dual O2S strategy is based on the fact that as a cat-alyst deteriorates, its oxygen storage capacity and its
efficiency are both reduced. By monitoring the oxy-
gen storage capacity of a catalyst, its efficiency can
be indirectly calculated. The upstream O2S is used to
detect the amount of oxygen in the exhaust gas
before the gas enters the catalytic converter. The
PCM calculates the A/F mixture from the output of
the O2S. A low voltage indicates high oxygen content
(lean mixture). A high voltage indicates a low content
of oxygen (rich mixture).
When the upstream O2S detects a lean condition,
there is an abundance of oxygen in the exhaust gas.
A functioning converter would store this oxygen so it
can use it for the oxidation of HC and CO. As the
converter absorbs the oxygen, there will be a lack of
oxygen downstream of the converter. The output of
the downstream O2S will indicate limited activity in
this condition.
As the converter loses the ability to store oxygen,
the condition can be detected from the behavior of
the downstream O2S. When the efficiency drops, no
chemical reaction takes place. This means the con-
centration of oxygen will be the same downstream as
upstream. The output voltage of the downstream
O2S copies the voltage of the upstream sensor. The
only difference is a time lag (seen by the PCM)
between the switching of the O2S's.
To monitor the system, the number of lean-to-rich
switches of upstream and downstream O2S's is
counted. The ratio of downstream switches to
upstream switches is used to determine whether the
catalyst is operating properly. An effective catalyst
will have fewer downstream switches than it has
upstream switches i.e., a ratio closer to zero. For a
totally ineffective catalyst, this ratio will be one-to-
one, indicating that no oxidation occurs in the device.
The system must be monitored so that when cata-
lyst efficiency deteriorates and exhaust emissions
increase to over the legal limit, the MIL (check
engine lamp) will be illuminated.
Monitor OperationÐTo monitor catalyst effi-
ciency, the PCM expands the rich and lean switch
points of the heated oxygen sensor. With extended
switch points, the air/fuel mixture runs richer and
leaner to overburden the catalytic converter. Once
the test is started, the air/fuel mixture runs rich and
lean and the O2 switches are counted. A switch is
counted when an oxygen sensor signal goes from
below the lean threshold to above the rich threshold.
The number of Rear O2 sensor switches is divided by
the number of Front O2 sensor switches to determine
the switching ratio.
The test runs for 20 seconds. As catalyst efficiency
deteriorated over the life of the vehicle, the switch
rate at the downstream sensor approaches that of the
upstream sensor. If at any point during the test
25 - 4 EMISSIONS CONTROLRS
EMISSIONS CONTROL (Continued)

The Task Manager Screen shows both a Requested
MIL state and an Actual MIL state. When the MIL is
illuminated upon completion of a test for a good trip,
the Requested MIL state changes to OFF. However,
the MIL remains illuminated until the next key
cycle. (On some vehicles, the MIL will actually turn
OFF during the thirdgood trip) During the key cycle
for the third good trip, the Requested MIL state is
OFF, while the Actual MIL state is ON. After the
next key cycle, the MIL is not illuminated and both
MIL states read OFF.
Diagnostic Trouble Codes (DTCs)
With OBD II, different DTC faults have different
priorities according to regulations. As a result, the
priorities determine MIL illumination and DTC era-
sure. DTCs are entered according to individual prior-
ity. DTCs with a higher priority overwrite lower
priority DTCs.
Priorities
²Priority 0 ÐNon-emissions related trouble codes.
²Priority 1 Ð One trip failure of a two trip fault
for non-fuel system and non-misfire. (MIL Off)
²Priority 2 Ð One trip failure of a two trip fault
for fuel system (rich/lean) or misfire. (MIL Off)
²Priority3ÐTwotrip failure for a non-fuel sys-
tem and non-misfire or matured one trip comprehen-
sive component fault. (MIL On)
²Priority4ÐTwotrip failure or matured fault
for fuel system (rich/lean) and misfire or one trip cat-
alyst damaging misfire. Catalyst damage misfire is a
2 trip MIL. The MIL flashes on the first trip when
catalyst damage misfire levels are present. (MIL On)
Non-emissions related failures have no priority.
One trip failures of two trip faults have low priority.
Two trip failures or matured faults have higher pri-
ority. One and two trip failures of fuel system and
misfire monitor take precedence over non-fuel system
and non-misfire failures.
DTC Self Erasure
With one trip components or systems, the MIL is
illuminated upon test failure and DTCs are stored.
Two trip monitors are components requiring failure
in two consecutive trips for MIL illumination. Upon
failure of the first test, the Task Manager enters a
maturing code. If the component fails the test for a
second time the code matures and a DTC is set.
After three good trips the MIL is extinguished and
the Task Manager automatically switches the trip
counter to a warm-up cycle counter. DTCs are auto-
matically erased following 40 warm-up cycles if the
component does not fail again.
For misfire and fuel system monitors, the compo-
nent must pass the test under a Similar Conditions
Window in order to record a good trip. A Similar Con-ditions Window is when engine RPM is within  375
RPM and load is within  20% of when the fault
occurred.
NOTE: It is important to understand that a compo-
nent does not have to fail under a similar window of
operation to mature. It must pass the test under a
Similar Conditions Window when it failed to record
a Good Trip for DTC erasure for misfire and fuel
system monitors.
DTCs can be erased anytime with a DRBIIIt.
Erasing the DTC with the DRBIIIterases all OBD II
information. The DRBIIItautomatically displays a
warning that erasing the DTC will also erase all
OBD II monitor data. This includes all counter infor-
mation for warm-up cycles, trips and Freeze Frame.
Trip Indicator
TheTripis essential for running monitors and
extinguishing the MIL. In OBD II terms, a trip is a
set of vehicle operating conditions that must be met
for a specific monitor to run. All trips begin with a
key cycle.
Good Trip
The Good Trip counters are as follows:
²Global Good Trip
²Fuel System Good Trip
²Misfire Good Trip
²Alternate Good Trip (appears as a Global Good
Trip on DRBIIIt)
²Comprehensive Components
²Major Monitor
²Warm-Up Cycles
Global Good Trip
To increment a Global Good Trip, the Oxygen sen-
sor and Catalyst efficiency monitors must have run
and passed, and 2 minutes of engine run time.
Fuel System Good Trip
To count a good trip (three required) and turn off
the MIL, the following conditions must occur:
²Engine in closed loop
²Operating in Similar Conditions Window
²Short Term multiplied by Long Term less than
threshold
²Less than threshold for a predetermined time
If all of the previous criteria are met, the PCM will
count a good trip (three required) and turn off the
MIL.
Misfire Good Trip
If the following conditions are met the PCM will
count one good trip (three required) in order to turn
off the MIL:
²Operating in Similar Condition Window
²1000 engine revolutions with no misfire
RSON-BOARD DIAGNOSTICS25-25
TASK MANAGER (Continued)