2004 CHRYSLER VOYAGER Power system

blower motor to regulate the blower motor ground
path it provides. The blower motor and wheel are
used to control the velocity of air moving through the
HVAC housing by spinning the blower wheel within
the housing at the selected speed or, in the ATC sys-
tem, at the selected or programmed speed.
DIAGNOSIS AND TESTING - BLOWER MOTOR
BLOWER MOTOR INOPERATIVE
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, DISABLE THE AIRBAG SYSTEM BEFORE
ATTEMPTING ANY STEERING WHEEL, STEERING
COLUMN, OR INSTRUMENT PANEL COMPONENT
DIAGNOSIS OR SERVICE. DISCONNECT AND ISO-
LATE THE BATTERY NEGATIVE (GROUND) CABLE,
THEN WAIT TWO MINUTES FOR THE AIRBAG SYS-
TEM CAPACITOR TO DISCHARGE BEFORE PER-
FORMING FURTHER DIAGNOSIS OR SERVICE. THIS
IS THE ONLY SURE WAY TO DISABLE THE AIRBAG
SYSTEM. FAILURE TO TAKE THE PROPER PRE-
CAUTIONS COULD RESULT IN ACCIDENTAL AIR-
BAG DEPLOYMENT AND POSSIBLE PERSONAL
INJURY.
For circuit descriptions and diagrams, refer to the
appropriate wiring information. The wiring informa-
tion includes wiring, diagrams, proper wire and con-
nector repair procedures, further details on wire
harness routing and retention, as well as pin-out and
location views for the various wire harness connec-
tors, splices and grounds.
BLOWER MOTOR ELECTRICAL DIAGNOSIS
(1) Check the fuse (Fuse 10 - 40 ampere) in the
Integrated Power Module (IPM). If OK, go to Step 2.
If not OK, repair the shorted circuit or component as
required and replace the faulty fuse.
(2) Turn the ignition switch to the On position. Be
certain that the A/C-heater control power is turned
on. Check for battery voltage at the fuse (Fuse 10 -
40 ampere) in the IPM. If OK, go to Step 3. If not
OK, check the front blower motor relay.
(3) Turn the ignition switch to the Off position.
Disconnect and isolate the battery negative cable.
Disconnect the front HVAC wire harness connector
for the front blower motor resistor block (Manual
Temperature Control) or the front blower motor
power module (Automatic Temperature Control) from
the resistor or module connector receptacle. Recon-
nect the battery negative cable. Turn the ignition
switch to the On position. Be certain that the A/C-
heater control power is turned on. Check for battery
voltage at the fused front blower motor relay output
circuit cavity of the front HVAC wire harness connec-
tor for the front blower motor resistor block (MTC) orthe front blower motor power module (ATC). If OK,
go to Step 4. If not OK, repair the open fused front
blower motor relay output circuit to the IPM as
required.
(4) Turn the ignition switch to the Off position.
Disconnect and isolate the battery negative cable.
Disconnect the front blower motor pigtail wire con-
nector from the connector receptacle of the front
blower motor resistor block (MTC) or the front
blower motor power module (ATC). Use jumper wires
to connect a battery and ground feeds to the blower
motor pigtail wire connector. The blower motor
should operate. If OK with MTC, proceed to diagno-
sis of the front blower motor resistor block (Refer to
24 - HEATING & AIR CONDITIONING/CONTROLS
- FRONT/BLOWER MOTOR RESISTOR - DIAGNO-
SIS AND TESTING). If OK with ATC, use a DRBIII
scan tool to diagnose the front blower motor power
module. Refer to Body Diagnostic information. If not
OK with MTC or ATC, replace the faulty front blower
motor.
BLOWER MOTOR NOISE OR VIBRATION
Refer to the Blower Motor Noise/Vibration Diagno-
sis chart for basic checks of the blower motor when a
vibration or noise is present (Fig. 7).
REMOVAL
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, DISABLE THE AIRBAG SYSTEM BEFORE
ATTEMPTING ANY STEERING WHEEL, STEERING
COLUMN, OR INSTRUMENT PANEL COMPONENT
DIAGNOSIS OR SERVICE. DISCONNECT AND ISO-
LATE THE BATTERY NEGATIVE (GROUND) CABLE,
THEN WAIT TWO MINUTES FOR THE AIRBAG SYS-
TEM CAPACITOR TO DISCHARGE BEFORE PER-
FORMING FURTHER DIAGNOSIS OR SERVICE. THIS
IS THE ONLY SURE WAY TO DISABLE THE AIRBAG
SYSTEM. FAILURE TO TAKE THE PROPER PRE-
CAUTIONS COULD RESULT IN AN ACCIDENTAL
AIRBAG DEPLOYMENT AND POSSIBLE PERSONAL
INJURY.
NOTE: The blower motor is located on the passen-
ger side of the vehicle under the instrument panel.
The blower motor can be removed from the vehicle
without having to remove the HVAC housing.
(1) Disconnect and isolate the battery negative
cable.
(2) Remove the passenger side door sill plate and
cowl panel.
(3) Pull back the carpet to access the front lower
air intake screw.
RSDISTRIBUTION - FRONT24-47
BLOWER MOTOR (Continued)

(6) Install the four screws (from the bottom) that
secure the lower air inlet housing to the lower HVAC
housing. Tighten the screws to 2 N´m (17 in. lbs.).
(7) Install the one screw (from the top) that
secures the lower air inlet housing to the upper air
intake housing. Tighten the screws to 2 N´m (17 in.
lbs.).
(8) Connect the blower motor pigtail harness con-
nector to the blower motor resistor block or power
module, depending how vehicle is equipped.
(9) Install the recirculation door actuator (Refer to
24 - HEATING & AIR CONDITIONING/CONTROLS/
RECIRCULATION DOOR ACTUATOR - INSTALLA-
TION).
(10) Install the recirculation door actuator wire
harness lead into the routing clip on the lower air
inlet housing.
(11) Reinstall the carpet.
(12) Install the passenger side door sill plate and
cowl panel.
(13) Reconnect the battery negative cable.
(14) Perform the heater-A/C control calibration
procedure (Refer to 24 - HEATING & AIR CONDI-
TIONING/CONTROLS - FRONT/A/C-HEATER CON-
TROL - STANDARD PROCEDURE - HEATER-A/C
CONTROL CALIBRATION).
DEFROSTER DUCT
REMOVAL
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, DISABLE THE AIRBAG SYSTEM BEFORE
ATTEMPTING ANY STEERING WHEEL, STEERING
COLUMN, OR INSTRUMENT PANEL COMPONENT
DIAGNOSIS OR SERVICE. DISCONNECT AND ISO-
LATE THE BATTERY NEGATIVE (GROUND) CABLE,
THEN WAIT TWO MINUTES FOR THE AIRBAG SYS-
TEM CAPACITOR TO DISCHARGE BEFORE PER-
FORMING FURTHER DIAGNOSIS OR SERVICE. THIS
IS THE ONLY SURE WAY TO DISABLE THE AIRBAG
SYSTEM. FAILURE TO TAKE THE PROPER PRE-
CAUTIONS COULD RESULT IN ACCIDENTAL AIR-
BAG DEPLOYMENT AND POSSIBLE PERSONAL
INJURY.
(1) Disconnect and isolate the battery negative
cable.
(2) Remove the instrument panel from the vehicle.
(Refer to 23 - BODY/INSTRUMENT PANEL/IN-
STRUMENT PANEL ASSEMBLY - REMOVAL).
(3) Place the instrument panel face down on a
suitable work surface. Be certain to take the proper
precautions to protect the face of the instrument
panel from cosmetic damage.(4) Remove the fasteners that secure the defroster
duct to the instrument panel armature.
(5) Remove the defroster duct from the instrument
panel.
INSTALLATION
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, DISABLE THE AIRBAG SYSTEM BEFORE
ATTEMPTING ANY STEERING WHEEL, STEERING
COLUMN, OR INSTRUMENT PANEL COMPONENT
DIAGNOSIS OR SERVICE. DISCONNECT AND ISO-
LATE THE BATTERY NEGATIVE (GROUND) CABLE,
THEN WAIT TWO MINUTES FOR THE AIRBAG SYS-
TEM CAPACITOR TO DISCHARGE BEFORE PER-
FORMING FURTHER DIAGNOSIS OR SERVICE. THIS
IS THE ONLY SURE WAY TO DISABLE THE AIRBAG
SYSTEM. FAILURE TO TAKE THE PROPER PRE-
CAUTIONS COULD RESULT IN ACCIDENTAL AIR-
BAG DEPLOYMENT AND POSSIBLE PERSONAL
INJURY.
(1) Position the defroster duct to the instrument
panel.
(2) Install the fasteners that secure the defroster
duct to the instrument panel armature.
(3) Reinstall the instrument panel in the vehicle.
(Refer to 23 - BODY/INSTRUMENT PANEL/IN-
STRUMENT PANEL ASSEMBLY - INSTALLA-
TION).
(4) Reconnect the battery negative cable.
FLOOR DISTRIBUTION DUCTS
REMOVAL
(1) Roll back the carpet on the front floor from
under the instrument panel toward the rear of the
vehicle (Refer to 23 - BODY/INTERIOR/CARPETS
AND FLOOR MATS - REMOVAL).
(2) Lift the center floor distribution duct upward
far enough to disengage its locator hole from the
weld stud on the front floor panel (Fig. 11).
(3) Pull the center floor distribution duct rearward
far enough to disengage it from the floor outlet of the
HVAC housing.
(4) Disassemble the right and/or left floor distribu-
tion ducts from the center floor distribution duct as
required.
INSTALLATION
(1) Assemble the right and/or left floor distribution
ducts onto the center floor distribution duct as
required.
(2) Slide the center floor distribution duct under
the instrument panel center stack far enough to
engage it to the floor outlet of the HVAC housing.
24 - 50 DISTRIBUTION - FRONTRS
BLOWER MOTOR (Continued)

DISTRIBUTION DUCT
REMOVAL
(1) Remove the trim from the right quarter inner
panel and the right D pillaR (Refer to 23 - BODY/IN-
TERIOR/RIGHT QUARTER TRIM PANEL -
REMOVAL).
(2) Slide the rear distribution duct upwards far
enough to disengage it from the outlet at the top of
the rear HVAC housing (Fig. 2).
(3) While pulling the lower end of the rear distri-
bution duct away from the rear HVAC housing out-
let, disengage the upper end of the distribution duct
from the headliner duct.
(4) Remove the rea distribution duct from the
vehicle.
INSTALLATION
(1) Align the upper end of the rear distribution
duct to the headliner duct.
(2) Slide the upper end of the rear distribution
duct onto the headliner duct far enough to align the
lower end of the duct with the outlet at the top of the
rear HVAC housing.
(3) Slide the rear distribution duct downwards far
enough to engage it onto the outlet at the top of the
rear HVAC housing.
(4) Reinstall the trim onto the right quarter inner
panel and the right D pillar (Refer to 23 - BODY/IN-
TERIOR/RIGHT QUARTER TRIM PANEL -
INSTALLATION).
BLOWER MOTOR
DESCRIPTION
The blower motor is a 12-volt, Direct Current (DC)
motor with a squirrel cage-type blower wheel that is
secured to the blower motor shaft. The blower motor
and wheel are located near the top of the rear HVAC
housing in the passenger compartment behind the
right rear wheel house. The rear HVAC housing must
be removed from the vehicle to access the blower
motor for service. The blower motor and blower
motor wheel are a factory balanced unit and cannot
be adjusted or repaired. If faulty or damaged, the
blower motor and blower wheel must be replaced as
a unit.
OPERATION
On models equipped with the Manual Temperature
Control (MTC) system, the rear blower motor will
operate only whenever the ignition switch is in the
On position, the front blower control switch is in any
position except Off and the rear blower control switch
on the front A/C-heater control is in any position
except Off. On models equipped with the Automatic
Temperature Control (ATC) system, the blower motor
will operate whenever the ignition switch is in the
On position, the A/C-heater control power is turned
on and the rear blower control switch on the front
A/C-heater control is in any position except Off. The
rear blower motor can only be turned off by turning
off the rear system at the front A/C-heater control.
The rear blower motor receives battery current
whenever the rear blower motor relay is energized.
The rear blower motor relay output circuit is pro-
tected by a fuse in the Integrated Power Module
(IPM) located in the engine compartment near the
battery. In the MTC system, the rear blower motor
speed is controlled by regulating the path to ground
through the blower control switch and the blower
motor resistor. In the ATC system, the rear blower
motor speed is controlled by an electronic blower
motor power module, which uses a pulse width mod-
ulated input from the ATC control module and feed-
back from the rear blower motor to regulate the
blower motor ground path it provides. The rear
blower motor and wheel are used to control the veloc-
ity of air moving through the rear HVAC housing.
The rear blower motor controls the velocity of the air
flowing through the rear HVAC housing by spinning
the blower wheel within the housing at the selected
speed or, in the ATC system, at the selected or pro-
grammed speed.
Fig. 2 Rear Distribution Duct
1 - HEADLINER DUCT
2 - REAR DISTRIBUTION DUCT
3 - REAR HVAC HOUSING OUTLET
RSDISTRIBUTION - REAR24-57

DIAGNOSIS AND TESTING - REAR BLOWER
MOTOR
BLOWER MOTOR INOPERATIVE
For circuit descriptions and diagrams, refer to the
appropriate wiring information. The wiring informa-
tion includes wiring, diagrams, proper wire and con-
nector repair procedures, further details on wire
harness routing and retention, as well as pin-out and
location views for the various wire harness connec-
tors, splices and grounds.
BLOWER MOTOR ELECTRICAL DIAGNOSIS
(1) Check the fuse (Fuse 12 - 25 ampere) in the
Integrated Power Module (IPM). If OK, go to Step 2.
If not OK, repair the shorted circuit or component as
required and replace the faulty fuse.
(2) Turn the ignition switch to the On position. Be
certain that the rear A/C-heater control power is
turned on. Check for battery voltage at the fuse
(Fuse 12 - 25 ampere) in the IPM. If OK, go to Step
3. If not OK, check the rear blower motor relay.
(3) Turn the ignition switch to the Off position.
Disconnect and isolate the battery negative cable.
Disconnect the rear HVAC wire harness connector
from the rear blower motor resistor block (Manual
Temperature Control) or the rear blower motor power
module (Automatic Temperature Control). Reconnect
the battery negative cable. Turn the ignition switch
to the On position. Be certain that the rear A/C-
heater control power is turned on. Check for battery
voltage at the fused rear blower motor relay output
circuit cavity of the rear HVAC wire harness connec-
tor for the rear blower motor resistor block (MTC) or
the rear blower motor power module (ATC). If OK, go
to Step 4. If not OK, repair the open fused front
blower motor relay output circuit to the IPM as
required.
(4) Turn the ignition switch to the Off position.
Disconnect and isolate the battery negative cable.
Disconnect the rear blower motor pigtail wire connec-
tor from the rear HVAC wire harness (MTC) or the
rear blower power module (ATC). Use jumper wires
to connect a battery and ground feeds to the blower
motor pigtail wire connector. The rear blower motor
should operate. If OK with MTC, proceed to diagno-
sis of the rear blower motor resistor block (Refer to
24 - HEATING & AIR CONDITIONING/CONTROLS
- REAR/BLOWER MOTOR RESISTOR - DIAGNOSIS
AND TESTING). If OK with ATC, use a DRBIII scan
tool to diagnose the rear blower motor power module.
Refer to the appropriate diagnostic information. If
not OK with MTC or ATC, replace the faulty rear
blower motor.BLOWER MOTOR NOISE OR VIBRATION
Refer to the Blower Motor Noise/Vibration Diagno-
sis chart for basic checks of the blower motor when a
vibration or noise is present (Fig. 3).
REMOVAL
WARNING: REFER TO THE APPLICABLE WARN-
INGS AND CAUTIONS FOR THIS SYSTEM BEFORE
PERFORMING THE FOLLOWING OPERATION (Refer
to 24 - HEATING & AIR CONDITIONING/PLUMBING -
WARNING) and (Refer to 24 - HEATING & AIR CON-
DITIONING/PLUMBING - CAUTION).
(1) Remove the rear HVAC housing from the vehi-
cle (Refer to 24 - HEATING & AIR CONDITIONING/
DISTRIBUTION/HVAC HOUSING - REMOVAL).
(2) Disconnect the rear blower motor pigtail wire
connector.
NOTE: With the Manual Temperature Control sys-
tem, the blower motor pigtail wire is connected to a
take out and connector of the rear HVAC wire har-
ness. With the Automatic Temperature Control sys-
tem , the blower pigtail wire is connected to a
receptacle on the blower motor power module.
(3) Remove the three screws that secure the rear
blower motor to the outboard side of the rear HVAC
housing (Fig. 4).
(4) Remove the rear blower motor from the rear
HVAC housing.
INSTALLATION
(1) Position the rear blower motor into the rear
HVAC housing.
(2) Install the three screws that secure the blower
motor to the rear HVAC housing. Tighten the screws
to 2 N´m (17 in. lbs.).
(3) Reconnect the rear blower motor pigtail wire
connector.
NOTE: With the Manual Temperature Control system
, the blower pigtail wire is connected to a take out
and connector of the rear HVAC wire harness. With
the Automatic Temperature Control system, the
blower pigtail wire is connected to a receptacle on
the blower motor power module.
24 - 58 DISTRIBUTION - REARRS
BLOWER MOTOR (Continued)

(9) Remove the heater core tubes and sealing plate
as a unit from beneath the instrument panel.
(10) Use absorbent toweling to clean up any
engine coolant spills from the preceding operation.
REMOVAL - HEATER CORE
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, DISABLE THE AIRBAG SYSTEM BEFORE
ATTEMPTING ANY STEERING WHEEL, STEERING
COLUMN, OR INSTRUMENT PANEL COMPONENT
DIAGNOSIS OR SERVICE. DISCONNECT AND ISO-
LATE THE BATTERY NEGATIVE (GROUND) CABLE,
THEN WAIT TWO MINUTES FOR THE AIRBAG SYS-
TEM CAPACITOR TO DISCHARGE BEFORE PER-
FORMING FURTHER DIAGNOSIS OR SERVICE. THIS
IS THE ONLY SURE WAY TO DISABLE THE AIRBAG
SYSTEM. FAILURE TO TAKE THE PROPER PRE-
CAUTIONS COULD RESULT IN ACCIDENTAL AIR-
BAG DEPLOYMENT AND POSSIBLE PERSONAL
INJURY.
(1) Remove the silencer boot fasteners located
around the base of the lower steering shaft from the
dash panel so that it may be pushed aside.
(2) Remove the brake lamp switch from its mount-
ing bracket (Refer to 8 - ELECTRICAL/LAMPS/
LIGHTING - EXTERIOR/BRAKE LAMP SWITCH -
REMOVAL).
(3) Disconnect the power brake booster input rod
(push rod) from the pin on the brake pedal arm
(Refer to 5 - BRAKES - ABS/HYDRAULIC/ME-CHANICAL/POWER BRAKE BOOSTER -
REMOVAL).
(4) Remove the heater core tubes (Refer to 24 -
HEATING & AIR CONDITIONING/PLUMBING/
HEATER CORE - REMOVAL).
(5) Remove the two screws that secure the heater
core mounting plate to the distribution housing.
(6) While pulling the accelerator pedal upward
(Fig. 15) and pushing the brake pedal downward
(Fig. 16) far enough for clearance, pull the heater
core out of the distribution housing.
(7) Use absorbent toweling to mop up any engine
coolant spills from the preceding operation. Also, if
the heater core was leaking, use absorbent toweling
and reach into the heater core opening to mop up
any residual engine coolant within the distribution
housing.
Fig. 14 Heater Core Tubes - LHD Shown, RHD
Typical
1 - SEAL
2 - HEATER CORE TUBES
3 - SCREW
4 - HEATER CORE
5 - DISTRIBUTION HOUSING
6 - SEALING PLATE
Fig. 15 Accelerator Pedal - LHD Shown, RHD Typical
1 - HEATER CORE
Fig. 16 Brake Pedal - LHD Shown, RHD Typical
1 - HEATER CORE
2 - BRAKE PEDAL
24 - 84 PLUMBING - FRONTRS
HEATER CORE (Continued)

INSTALLATION
INSTALLATION - HEATER CORE TUBES
(1) Remove the plugs or tape from both heater core
tube fittings and both heater core ports.
(2) Position the heater core tubes and sealing plate
as a unit beneath the instrument panel.
(3) Align the engine compartment ends of both
heater core tubes with the openings in the dash
panel seal and push them simultaneously forward
through the seal far enough to engage the heater
core ends of the tubes with the heater core supply
and return ports.
(4) Position both heater core tubes and the sealing
plate simultaneously to the heater core supply and
return ports.
NOTE: The heater core tubes each have a slot that
must be indexed to a location tab within each of the
heater core ports. Adjust the position of the tubes
as required so that the sealing plate fits flush
against the heater core supply and return ports,
which indicates that the tubes are properly indexed.
(5) Index both heater core tubes to the heater core
ports.
(6) Install the screw that secures the heater core
tube sealing plate to the heater core supply and
return ports. Tighten the screw to 3 N´m (27 in. lbs.).
(7) Install the silencer under the driver side end of
the instrument panel.
(8) Connect the heater hoses to the heater hose
tubes (Refer to 24 - HEATING & AIR CONDITION-
ING/PLUMBING/HEATER INLET HOSE - INSTAL-
LATION) and(Refer to 24 - HEATING & AIR
CONDITIONING/PLUMBING/HEATER RETURN
HOSE - INSTALLATION).
(9) Reconnect the battery negative cable.
(10) Refill the engine cooling system (Refer to 7 -
COOLING - STANDARD PROCEDURE - COOLING
SYSTEM REFILL).
INSTALLATION - HEATER CORE
(1) While pushing the brake pedal downward and
pulling the accelerator pedal upward far enough for
clearance, slide the heater core into the distribution
housing.
(2) Install the two screws that secure the heater
core mounting plate to the distribution housing.
Tighten the screws to 2 N´m (17 in. lbs.).
(3) Install the heater core tubes (Refer to 24 -
HEATING & AIR CONDITIONING/PLUMBING/
HEATER CORE - INSTALLATION).
(4) Reconnect the power brake booster input rod
(push rod) to the pin on the brake pedal arm (Referto 5 - BRAKES/HYDRAULIC/MECHANICAL/
POWER BRAKE BOOSTER - INSTALLATION).
(5) Reinstall the brake lamp switch into its mount-
ing bracket (Refer to 8 - ELECTRICAL/LAMPS/
LIGHTING - EXTERIOR/BRAKE LAMP SWITCH -
INSTALLATION).
(6) Reinstall the silencer boot around the base of
the lower steering shaft on the dash panel.
(7) Reconnect the battery negative cable.
(8) Refill the engine cooling system (Refer to 7 -
COOLING - STANDARD PROCEDURE - COOLING
SYSTEM REFILL).
(9) Operate system for two thermostat cycles to
assure the elimination of any air that may be
trapped within the cooling system.
HEATER INLET HOSE
REMOVAL
WARNING: REFER TO THE APPLICABLE WARN-
INGS AND CAUTIONS FOR THIS SYSTEM BEFORE
PERFORMING THE FOLLOWING OPERATION (Refer
to 24 - HEATING & AIR CONDITIONING/PLUMBING -
WARNING).
NOTE: The heater inlet hose is constructed from
formed steel tubing and rubber hoses. Depending
on application, the ends are secured to the heater
core, engine oil cooler or the engine by spring ten-
sion clamps.
(1) Drain the engine cooling system (Refer to 7 -
COOLING - STANDARD PROCEDURE - COOLING
SYSTEM DRAIN).
(2) Using spring tension clamp pliers, compress
and slide the clamps off of each end of the hose being
removed (Fig. 17), (Fig. 18) or (Fig. 19).
CAUTION:
DO NOT apply excessive pressure on heater tubes
or connections when removing heater hoses.
Excessive pressure may damage or deform the
tubes/heater core, causing an engine coolant leak.
(3) Disconnect each hose end by carefully twisting
the hose back and forth on the tube or nipple, while
gently pulling it away from the end of the tube or
nipple.
NOTE:
Replacement of the heater inlet hoses will be
required if the hose ends are cut for removal.
(4) If necessary, carefully cut the hose end and
peel the hose off of the tube or nipple.
RSPLUMBING - FRONT24-85
HEATER CORE (Continued)

EMISSIONS CONTROL
TABLE OF CONTENTS
page page
EMISSIONS CONTROL
DESCRIPTION
DESCRIPTION - VEHICLE EMISSION
CONTROL INFORMATION LABEL..........1
DESCRIPTION - TRIP DEFINITION.........1
DESCRIPTION - MONITORED COMPONENT . 1
OPERATION - NON-MONITORED CIRCUITS . . 5
DESCRIPTION - MONITORED SYSTEMS....6DESCRIPTION - HIGH AND LOW LIMITS....8
OPERATION
OPERATION - SYSTEM..................9
DRB IIITSTATE DISPLAY TEST MODE......9
EVAPORATIVE EMISSIONS................10
EXHAUST GAS RECIRCULATION...........21
ON-BOARD DIAGNOSTICS................24
EMISSIONS CONTROL
DESCRIPTION
DESCRIPTION - VEHICLE EMISSION CONTROL
INFORMATION LABEL
All models have a Vehicle Emission Control Infor-
mation (VECI) Label. Chrysler permanently attaches
the label in the engine compartment. It cannot be
removed without defacing information and destroying
the label.
The label contains the vehicle's emission specifica-
tions and vacuum hose routings. All hoses must be
connected and routed according to the label.
DESCRIPTION - TRIP DEFINITION
A ªTripº means vehicle operation (following an
engine-off period) of duration and driving mode such
that all components and systems are monitored at
least once by the diagnostic system. The monitors
must successfully pass before the PCM can verify
that a previously malfunctioning component is meet-
ing the normal operating conditions of that compo-
nent. For misfire or fuel system malfunction, the
MIL may be extinguished if the fault does not recur
when monitored during three subsequent sequential
driving cycles in which conditions are similar to
those under which the malfunction was first deter-
mined.
Anytime the MIL is illuminated, a DTC is stored.
The DTC can self erase only after the MIL has been
extinguished. Once the MIL is extinguished, the
PCM must pass the diagnostic test for the most
recent DTC for 40 warm-up cycles (80 warm-up
cycles for the Fuel System Monitor and the Misfire
Monitor). A warm-up cycle can best be described by
the following:
²The engine must be running²A rise of 40ÉF in engine temperature must occur
from the time when the engine was started
²Engine coolant temperature must crossover
160ÉF
²A ªdriving cycleº that consists of engine start up
and engine shut off.
Once the above conditions occur, the PCM is con-
sidered to have passed a warm-up cycle. Due to the
conditions required to extinguish the MIL and erase
the DTC, it is most important that after a repair has
been made, all DTC's be erased and the repair veri-
fied by running 1±good trip.
DESCRIPTION - MONITORED COMPONENT
There are several components that will affect vehi-
cle emissions if they malfunction. If one of these com-
ponents malfunctions the Malfunction Indicator
Lamp (Check Engine) will illuminate.
Some of the component monitors are checking for
proper operation of the part. Electrically operated
components now have input (rationality) and output
(functionality) checks. Previously, a component like
the Throttle Position sensor (TPS) was checked by
the PCM for an open or shorted circuit. If one of
these conditions occurred, a DTC was set. Now there
is a check to ensure that the component is working.
This is done by watching for a TPS indication of a
greater or lesser throttle opening than MAP and
engine rpm indicate. In the case of the TPS, if engine
vacuum is low and engine rpm is 1600 or greater and
the TPS indicates a small throttle opening, a DTC
will be set.
Any component that has an associated limp in will
set a fault after 1 trip with the malfunction present.
Refer to the Diagnostic Trouble Codes Description
Charts (Refer to 8 - ELECTRICAL/ELECTRONIC
CONTROL MODULES/POWERTRAIN CONTROL
MODULE - DESCRIPTION) and the appropriate
Powertrain Diagnostic Procedure Manual for diag-
nostic procedures.
RSEMISSIONS CONTROL25-1

The following is a list of the monitored compo-
nents:
²Comprehensive Components
²Oxygen Sensor Monitor
²Oxygen Sensor Heater Monitor
²Catalyst Monitor
COMPREHENSIVE COMPONENTS
Along with the major monitors, OBD II requires
that the diagnostic system monitor any component
that could affect emissions levels. In many cases,
these components were being tested under OBD I.
The OBD I requirements focused mainly on testing
emissions-related components for electrical opens and
shorts.
However, OBD II also requires that inputs from
powertrain components to the PCM be tested for
rationality, and that outputs to powertrain compo-
nents from the PCM be tested forfunctionality.
Methods for monitoring the various Comprehensive
Component monitoring include:
(1) Circuit Continuity
²Open
²Shorted high
²Shorted to ground
(2) Rationality or Proper Functioning
²Inputs tested for rationality
²Outputs tested for functionality
NOTE: Comprehensive component monitors are
continuous. Therefore, enabling conditions do not
apply.
Input RationalityÐWhile input signals to the
PCM are constantly being monitored for electrical
opens and shorts, they are also tested for rationality.
This means that the input signal is compared against
other inputs and information to see if it makes sense
under the current conditions.
PCM sensor inputs that are checked for rationality
include:
²Manifold Absolute Pressure (MAP) Sensor
²Oxygen Sensor (O2S)
²Engine Coolant Temperature (ECT) Sensor
²Camshaft Position (CMP) Sensor
²Vehicle Speed Sensor
²Crankshaft Position (CKP) Sensor
²Intake/inlet Air Temperature (IAT) Sensor
²Throttle Position (TPS) Sensor
²Ambient Temperature Sensors
²Power Steering Switch
²Oxygen Sensor Heater
²Brake Switch
²Leak Detection Pump Switch or NVLD switch (if
equipped)
²P/N SwitchOutput FunctionalityÐPCM outputs are tested
for functionality in addition to testing for opens and
shorts. When the PCM provides a voltage to an out-
put component, it can verify that the command was
carried out by monitoring specific input signals for
expected changes. For example, when the PCM com-
mands the Idle Air Control (IAC) Motor to a specific
position under certain operating conditions, it expects
to see a specific (target) idle speed (RPM). If it does
not, it stores a DTC.
PCM outputs monitored for functionality include:
²Fuel Injectors
²Ignition Coils
²Idle Air Control
²Purge Solenoid
²EGR Solenoid (if equipped)
²LDP Solenoid or NVLD solenoid (if equipped)
²Radiator Fan Control
²Trans Controls
OXYGEN SENSOR (O2S) MONITOR
DESCRIPTIONÐEffective control of exhaust
emissions is achieved by an oxygen feedback system.
The most important element of the feedback system
is the O2S. The O2S is located in the exhaust path.
Once it reaches operating temperature 300É to 350ÉC
(572É to 662ÉF), the sensor generates a voltage that
is inversely proportional to the amount of oxygen in
the exhaust. When there is a large amount of oxygen
in the exhaust caused by a lean condition, the sensor
produces a low voltage, below 450 mV. When the oxy-
gen content is lower, caused by a rich condition, the
sensor produces a higher voltage, above 450mV (volt-
ages are offset by 2.5 volts on NGC vehicles).
The information obtained by the sensor is used to
calculate the fuel injector pulse width. The PCM is
programmed to maintain the optimum air/fuel ratio.
At this mixture ratio, the catalyst works best to
remove hydrocarbons (HC), carbon monoxide (CO)
and nitrous oxide (NOx) from the exhaust.
The O2S is also the main sensing element for the
EGR (if equipped), Catalyst and Fuel Monitors.
The O2S may fail in any or all of the following
manners:
²Slow response rate (Big Slope)
²Reduced output voltage (Half Cycle)
²Heater Performance
Slow Response Rate (Big Slope)ÐResponse rate
is the time required for the sensor to switch from
lean to rich signal output once it is exposed to a
richer than optimum A/F mixture or vice versa. As
the PCM adjusts the air/fuel ratio, the sensor must
be able to rapidly detect the change. As the sensor
ages, it could take longer to detect the changes in the
oxygen content of the exhaust gas. The rate of
change that an oxygen sensor experiences is called
25 - 2 EMISSIONS CONTROLRS
EMISSIONS CONTROL (Continued)