ECU CHRYSLER CARAVAN 2003 Service Manual

INSTALLATION
NOTE: If the rear heater core or the rear heater-A/C
housing have been removed from the vehicle for
service, the rear heater core may be pre-filled with
the proper engine coolant mixture prior to recon-
necting the heater hoses to the heater core hose fit-
tings. (Refer to 24 - HEATING & AIR CONDITIONING/
PLUMBING - REAR/HEATER CORE - STANDARD
PROCEDURE - HEATER CORE FILLING).
(1) Carefully slide the heater core into the rear
heater-A/C unit housing.
(2) Using hand pressure, press firmly and evenly
on the heater core end plate until the four latch tabs
that secure the heater core in the rear heater-A/C
unit housing are fully engaged (Fig. 5).
(3) Remove the plugs or tape from the heater core
fittings and both heater hoses.
(4) Reconnect the heater hoses to the rear heater
core. (Refer to 24 - HEATING & AIR CONDITION-
ING/PLUMBING - REAR/HEATER HOSE - INSTAL-
LATION).
(5) Install and tighten the screw that secures the
front of the rear heater-A/C unit housing to the right
quarter inner panel. Tighten the screw to 11 N´m (97
in. lbs.).
(6) Install and tighten the screw that secures the
back of the rear heater-A/C unit housing to the right
D-pillar. Tighten the screw to 11 N´m (97 in. lbs.).
(7) Reinstall the rear heater distribution duct onto
the right quarter inner panel. (Refer to 24 - HEAT-
ING & AIR CONDITIONING/DISTRIBUTION -REAR/REAR HEATER DISTRIBUTION DUCT -
INSTALLATION).
(8) Remove the right quarter trim panel and right
D-pillar trim panel from the quarter inner panel.
(Refer to 23 - BODY/INTERIOR/QUARTER TRIM
PANEL - INSTALLATION).
(9) Drain the engine cooling system. (Refer to 7 -
COOLING - STANDARD PROCEDURE - COOLING
SYSTEM REFILL).
HEATER HOSE
REMOVAL
REFER TO THE APPLICABLE WARNINGS AND
CAUTIONS FOR THIS SYSTEM BEFORE PER-
FORMING THE FOLLOWING OPERATION. (Refer
to 24 - HEATING & AIR CONDITIONING/PLUMB-
ING FRONT - WARNING - HEATER PLUMBING).
(1) Partially drain engine cooling system. Refer to
Group 7, Engine Cooling.
(2) Loosen clamp at the front end of the hose
located at the right, outboard side of the underbody,
rearward of the front crossmember. (Fig. 6)
(3) Carefully rotate hose back and forth while tug-
ging slightly away from connector nipple. If the hose
will not come off, slice the hose at the connector nip-
ple and peel off heater hose. This method will require
heater hose replacement.
CAUTION:
When removing hoses from outlet nipples, do not
use excessive force. Outlet nipples may become
damaged and leak engine coolant.
Fig. 5 Heater Core
1 - REAR HEATER-A/C HOUSING OUTLET
2 - REAR HEATER-A/C UNIT HOUSING
3 - LATCH (4)
4 - HEATER CORE
5 - RIGHT REAR WHEEL HOUSE
6 - HEATER HOSES
Fig. 6 Underbody Connections
1 - SUCTION LINE EXTENSION
2 - LIQUID LINE EXTENSION
3 - TIE STRAP
4- HEATER LINE EXTENSIONS
5 - UNDERBODY LINES
24 - 100 PLUMBING - REARRS
HEATER CORE (Continued)
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(4) Compress insert in rear heater hose quick con-
nection and pull downward on hose.
(5) Remove (3) straps securing underbody lines.
(6) Separate and remove rear heater lines from
vehicle.
INSTALLATION
There are several heater core plumbing configura-
tions used on this model, depending upon the engine
size and other optional equipment. One plumbing
configuration is used for all 2.4L engines, while the
3.3L and 3.8L engines have unique heater return
plumbing on the engine for models with or without
an optional engine oil cooler. There are also unique
plumbing configurations at the heater core for mod-
els with or without the optional rear heater and air
conditioner. All models use a combination of formed
steel tubing and rubber hoses. In most cases, the
rubber hose is secured to the steel tubing with a
spring tension clamp.
WARNING: REFER TO THE APPLICABLE WARN-
INGS AND CAUTIONS FOR THIS SYSTEM BEFORE
PERFORMING THE FOLLOWING OPERATION.
(Refer to 24 - HEATING & AIR CONDITIONING/
PLUMBING FRONT - WARNING - HEATER PLUMB-
ING).
(1) Using spring tension clamp pliers, compress
and slide the clamps that secure each end of the
heater hose toward the center of the hose being
installed. Release the clamp when it is near the cen-
ter of the hose.
(2) Grasp one end of the heater hose being
installed firmly and carefully twist the hose back and
forth while pushing it over from the barbed end of
the nipple. Repeat this procedure at the opposite end
of the hose being installed.
(3) Using spring tension clamp pliers, compress
and slide the clamps that secure each end of the
heater hose over the tube or nipple. Release the
clamp when it is over the tube or nipple.
(4) Refill the engine cooling system. (Refer to 7 -
COOLING - STANDARD PROCEDURE - COOLING
SYSTEM REFILL).
SUCTION LINE
REMOVAL
The front air conditioner suction line includes the
low side service port on a section of tubing located
near the compressor. On models equipped with the
optional rear air conditioner, the front air conditioner
suction line also includes a suction line hose and
tube extension that connects the front suction line to
the suction line for the rear air conditioner.WARNING: REFER TO THE APPLICABLE WARN-
INGS AND CAUTIONS FOR THIS SYSTEM BEFORE
PERFORMING THE FOLLOWING OPERATION.
(Refer to 24 - HEATING & AIR CONDITIONING/
PLUMBING - FRONT - WARNING - A/C PLUMBING)
and (Refer to 24 - HEATING & AIR CONDITIONING/
PLUMBING - FRONT - CAUTION - A/C PLUMBING).
(1) Recover the refrigerant from the refrigerant
system. (Refer to 24 - HEATING & AIR CONDI-
TIONING/PLUMBING - FRONT/REFRIGERANT -
STANDARD PROCEDURE - REFRIGERANT
RECOVERY).
(2) Disconnect and isolate the battery negative
cable.
(3) Remove the air cleaner top cover and snorkel
from the air cleaner housing located on the right side
of the engine compartment.
(4) Disconnect the drain tube from the wiper mod-
ule drain on the right side of the engine compart-
ment.
(5) Remove the nut that secures the suction line
fitting to the top of the compressor.
(6) Disconnect the suction line fitting from the
compressor suction port.
(7) Remove the seal from the suction line fitting
and discard.
(8) Install plugs in, or tape over the opened suc-
tion line fitting and the compressor suction port.
(9) Disengage the retainer that secures the suction
line routing clip to the filter-drier mounting bracket
on the side of the right front strut tower in the
engine compartment (Fig. 7).
(10) Remove the nut that secures the suction line
and liquid line fittings to the expansion valve.
(11) Disconnect the suction line and liquid line fit-
tings from the expansion valve.
(12) Remove the seals from the suction line and
liquid line fittings and discard.
(13) Install plugs in, or tape over the opened suc-
tion line and liquid line fittings and both expansion
valve ports.
(14) If the vehicle is equipped with the optional
rear air conditioner, go to Step 15. If the vehicle does
not have the optional rear air conditioner, go to Step
21.
(15) Raise and support the vehicle.
(16) Cut the tie strap located just forward of the
connections between the underbody plumbing and
the engine compartment plumbing for the rear
heater and air conditioner (Fig. 8).
(17) Disconnect the suction line extension fitting
from the underbody suction line fitting for the rear
air conditioner.
(18) Remove the seal from the underbody suction
line fitting and discard.
RSPLUMBING - REAR24 - 101
HEATER HOSE (Continued)
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(19) Install plugs in, or tape over the opened suc-
tion line fittings.
(20) Lower the vehicle.
(21) Remove the suction line from the engine com-
partment.
INSTALLATION
The front air conditioner suction line includes the
low side service port on a section of tubing located
near the compressor. On models equipped with the
optional rear air conditioner, the front air conditioner
suction line also includes a suction line hose and
tube extension that connects the front suction line to
the suction line for the rear air conditioner.
WARNING: REFER TO THE APPLICABLE WARN-
INGS AND CAUTIONS FOR THIS SYSTEM BEFORE
PERFORMING THE FOLLOWING OPERATION.
(Refer to 24 - HEATING & AIR CONDITIONING/
PLUMBING - FRONT - WARNING - A/C PLUMBING)
and (Refer to 24 - HEATING & AIR CONDITIONING/
PLUMBING - FRONT - CAUTION - A/C PLUMBING).
(1) Position the suction line into the engine com-
partment.
(2) Remove the tape or plugs from the suction line
and liquid line fittings and both expansion valve
ports.
(3) Lubricate new rubber O-ring seals with clean
refrigerant oil and install them on the suction line
and liquid line fittings.
(4) Reconnect the liquid line and suction line fit-
tings to the expansion valve.
(5) Install and tighten the nut that secures the
suction line and liquid line fittings to the expansion
valve. Tighten the nut to 23 N´m (17 ft. lbs.).
(6) Engage the retainer that secures the suction
line routing clip to the filter-drier mounting bracket
on the side of the right front strut tower in the
engine compartment.
(7) Remove the tape or plugs from the compressor
suction port and the suction line fitting.
(8) Lubricate a new rubber O-ring seal with clean
refrigerant oil and install it on the suction line fit-
ting.
(9) Reconnect the suction line fitting to the com-
pressor suction port.
(10) Install and tighten the nut that secures the
suction line fitting to the compressor. Tighten the nut
to 23 N´m (17 ft. lbs.).
(11) Reconnect the drain tube to the wiper module
drain on the right side of the engine compartment.
(12) Reinstall the air cleaner top cover and snorkel
onto the air cleaner housing located on the right side
of the engine compartment.
(13) Reconnect the battery negative cable.
(14) If the vehicle is equipped with the optional
rear air conditioner, go to Step 15. If the vehicle does
not have the optional rear air conditioner, go to Step
21.
(15) Raise and support the vehicle.
Fig. 7 Suction Line
1 - EXPANSION VALVE
2 - SUCTION LINE EXTENSION (REAR A/C ONLY)
3 - NUT
4 - ROUTING CLIP (If Equipped)
5 - SUCTION LINE
Fig. 8 Underbody Connections
1 - SUCTION LINE EXTENSION
2 - LIQUID LINE EXTENSION
3 - TIE STRAP
4- HEATER LINE EXTENSIONS
5 - UNDERBODY LINES
24 - 102 PLUMBING - REARRS
SUCTION LINE (Continued)
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REMOVAL
REMOVAL - REAR HEATER LINES
(1) Raise and support vehicle.
(2) Pinch off rubber heater line hose.
(3) Disconnect quick connect fitting at C-pillar.
(4) Loosen one screw and remove the other screw
at each of the three brackets holding the front of the
line to the underbody.
(5) Lower rear of line and drain coolant into a
suitable container.
(6) Loosen hose clamps at front of line and remove
line from vehicle.
REMOVAL - REAR AIR CONDITIONING LINES
(1) Recover A/C system.
(2) Hoist and support vehicle.
(3) Loosen one screw and remove the other screw
at each of the three brackets holding the A/C lines to
the underbody (Fig. 9).
(4) Remove both A/C lines from the two rear
retaining clamps, behind rear wheel.
(5) Remove both compression fittings at front of
A/C lines (Fig. 10).
(6) Remove (1) bolt securing A/C lines to block
located at A/C housing, behind rear wheel, and sepa-
rate block (Fig. 13).
(7) Remove rear wheel.
(8) Separate ABS harness from flex hose clamps.
(9) Remove heater lines from underbody brackets.
(10) Pinch off rubber heater line hoses at front of
vehicle.
Fig. 10 Front Lines Connected to Rear Lines
Fig. 11 Rear Heater Hose Connection
1 - REAR HEATER HOSE
Fig. 12 Rear heater hose quick connects
1 - INSERT
2 - QUICK CONNECT
3 - COMPRESS INSERT FOR REMOVAL
Fig. 13 Rear A/C Block Connection
1 - CLEAN AREA AROUND BLOCK BEFORE REMOVAL
24 - 104 PLUMBING - REARRS
UNDERBODY LINES (Continued)
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DIESEL SUPPLEMENTAL HEATER - DCHA - EXPORT
TABLE OF CONTENTS
page page
DIESEL SUPPLEMENTAL HEATER - DCHA -
EXPORT
DESCRIPTION........................106
OPERATION
OPERATION........................106
OPERATION - TWO ZONE ATC..........106
DIAGNOSIS AND TESTING - DIESEL
SUPPLEMENTAL HEATER - DCHA.......107
EXHAUST TUBE
REMOVAL............................107
INSTALLATION........................107
FUEL DOSING PUMP
DESCRIPTION........................108
OPERATION..........................108
REMOVAL............................108INSTALLATION........................108
FUEL LINE
STANDARD PROCEDURE - CLEANING.....109
REMOVAL............................109
INSTALLATION........................110
HEATER UNIT
REMOVAL............................111
INSTALLATION........................111
SUPPLEMENTAL DIESEL HEATER WIRING
REMOVAL............................112
INSTALLATION........................112
AIR INTAKE PIPE
REMOVAL............................112
INSTALLATION........................113
DIESEL SUPPLEMENTAL
HEATER - DCHA - EXPORT
DESCRIPTION
Vehicles equipped with the optional diesel engine
are also equipped with a supplemental heater unit.
This unit is mounted under the vehicle and operates
similar to an oil fired furnace. The heater burns
small amounts of fuel to provide additional heat to
the coolant. Coolant is routed from the engine, to the
supplemental heater, and then to the front heater
core. This provides additional heat to the passenger
compartment. The system is interfaced to the vehi-
cles on-board computer systems and DRB-III diag-
nostics.
The supplemental heater unit has a electronic con-
trol unit that monitors the heat output of the heater.
The heater operates at full load (5 kW), half load or
idle mode (no additional heat) depending on collant
temperature.
OPERATION
OPERATION
The supplemental heater unit is activated via the
temperature slide control or knob on the vehicle
HVAC control unit. If the control slide or knob is
moved to or above the upper set point the heater is
activated. The unit can operate in a full or partial
load range as well as an idle mode all dependent on
the engine coolant temperature. The heater unit willalso turn off if the HVAC temperature control is low-
ered to less than the lower set point. The heater unit
can take up to three minutes to completely shut
down when either the heater temperature is set
below the lower set point or the vehicle ignition is
shut down.
The supplemental heater only operates when the
engine is running, the mileage exceeds 8 kilometer (5
mph) and the fuel tank volume exceeds 1/8 of a tank.
The heater should start if the collant temperature is
below 40 degrees celsius (104 degrees F).
NOTE: Do not apply a strong vacuum directly on
the supplemtal heater exhaust line. Place the vac-
uum within 75 mm (3 inches) of the exhaust port.
Too strong of a vacuum can prevent the heater from
starting. The heater ECU monitors the supplemental
blower speed and combustion during its start-up.
OPERATION - TWO ZONE ATC
The Two Zone ATC control head will activate the
Supplemental Heater based on engine coolant tem-
perature and interior component settings. The unit
can operate in a full or partial load range as well as
an idle mode all dependent on the engine coolant
temperature. The unit will also turn off if the HVAC
temperature control setting is lowered to less than
the lower set point. The unit can take up to three
minutes to completely shut down when either the
heater temperature is set below the lower set point of
the vehicle ignition is shut down.
24 - 106 DIESEL SUPPLEMENTAL HEATER - DCHA - EXPORTRS
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The supplemental heater only operates when the
engine is running, the mileage exceeds 8 kilometers
(5 mph) and the fuel tank volume exceeds 1/8 of a
tank. The heater should start if the coolant temper-
ature is below 40 degrees celsius (104 degrees F).
NOTE: Do not apply a strong vacuum directly on
the supplemental heater exhaust line. Place the vac-
uum within 75 mm (3 inches) of the exhaust outlet
port. Too strong of a vacuum can prevent the heaterfrom starting. The heater ECU monitors the supple-
mental blower speed and combustion during its
start-up.
DIAGNOSIS AND TESTING - DIESEL
SUPPLEMENTAL HEATER - DCHA
The following table lists possible fault symptoms of
diesel fueled heaters.
SYMPTOM POSSIBLE CAUSES
Smell of diesel fuel Check heater system integration in vehicle's fuel system. Check fuel
lines for leakage, kinks or obstructions. If OK, Inspect the inlet muffler,
drain as necessary. Re-test the unit and re-inspect. Inspect the
exhaust tube and heater unit for the presence of external fuel. If a
volume is observed on the unit or in the exhaust tube or after draining
and testing. Remove heater unit from vehicle and repair or replace
components as required.
Heater does not achieve full load
operation.Check heater operation with DRB-III and replace components as
required.
Continuous white smoke from heater
exhaust during combustion operation.Check heater operation with DRB-III and replace components as
required. White smoke is typical in extreme weather conditions.
Heater can not be switched off. Check heater operation with DRB-III and replace components as
required.
Heater does not operate. Diagnosis cabin heater ECU using the DRB-III and the procedures
listed in Vehicle Performance under Cabin Heater Diagnosis in Group
18.
Loss of coolant (Leakage) or heater
develops smoke during combustion
operation and exhaust has an
extremely sweet smell.Inspect coolant hoses for leakage, kinks or loose hose connection.
Inspect the exhaust tube assembly for continuous flow, if OK there is
an internal heater leak and unit should be inspected and components
should be replaced as required.
Loss of fuel (dripping). Check heater system integration in vehicles fuel system. Check fuel
line connection for leakage. If OK there is an internal leak and unit
should be inspected and replaced as required.
EXHAUST TUBE
REMOVAL
WARNING: THERE IS A POTENTIAL DANGER OF
SKIN BURNS AS THE HEATER AND ITS COMPO-
NENTS MAY BE VERY HOT. MAKE SURE THE
HEATER IS ALLOWED TO COOL DOWN BEFORE
ANY SERVICE WORK ON THE CABIN HEATER SYS-
TEM IS ATTEMPTED.
(1) Elevate vehicle on a lift taking note of the
exhaust tube flexible section.
(2) Remove the exhaust clamp at the flexible pipe
and steel pipe connection (Fig. 1).
(3) Remove the clamp at the flexible pipe connec-
tion and the heater unit housing (if required).(4) Remove the three screws holding the exhaust
pipe to the body.
(5) Remove the steel exhaust pipe from the vehi-
cle.
(6) Remove the flexible exhaust pipe from the
vehicle (if required).
INSTALLATION
(1) Install the flexible exhaust pipe to the heater
unit. Tighten mounting clamp.
(2) Position the steel exhaust pipe to the flexible
exhaust and install and tighten the mounting clamp.
(3) Install the three exhaust pipe screws, adjust
pipe placement as needed and tighten the screws.
(4) Install the clamp to connect the steel exhaust
pipe to the flexible exhaust pipe and tighten clamp.
RSDIESEL SUPPLEMENTAL HEATER - DCHA - EXPORT24 - 107
DIESEL SUPPLEMENTAL HEATER - DCHA - EXPORT (Continued)
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INSTALLATION
WARNING: DO NOT OPERATE THE DCHA IN AN
ENCLOSED AREA SUCH AS A GARAGE THAT
DOES NOT HAVE EXHAUST VENTILATION FACILI-
TIES. ALWAYS VENT THE DCHA'S EXHAUST WHEN
OPERATING THE DCHA. FAILURE TO FOLLOW
THESE INSTRUCTIONS MAY RESULT IN PERSONAL
INJURY OR DEATH.
WARNING: ALLOW THE DCHA ASSEMBLY TO
COOL BEFORE PERFORMING A COMPONENT
INSPECTION/REPAIR/REPLACEMENT. FAILURE TO
FOLLOW THESE INSTRUCTIONS MAY RESULT IN
PERSONAL INJURY.
WARNING: VERIFY THAT ALL DCHA FUEL LINES
ARE SECURELY FASTENED TO THEIR RESPECTIVE
COMPONENTS BEFORE PERFORMING THIS PRO-
CEDURE.
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 heater fuel supply line to vehicle and
install in fuel line retainers
(2) Install fuel line connection at fuel tank and
tighten connection.
(3) Install fuel line at Dosing Pump and tighten
connection.
(4) Lower vehicle from lift.
NOTE: Failure to prime the Dosing Pump after
draining the DCHA fuel line will prevent DCHA
heater activation during the first attempt to start the
heater. This will also set a Diagnostic Trouble Code
(DCT) in the DCHA Control's memory. Do not per-
form the Dosing Pump Priming procedure if an
attempt was made to start the DCHA without prim-
ing the Dosing Pump first. This will put excess fuel
in the DCHA Heater Module and cause smoke to
emit from the DCHA exhaust pipe when heater acti-
vation occurs.
(5) Connect the DRBIIItto the Diagnostic Link
Connector.
(6) Turn the ignition to the on position.
Fig. 3 Dosing Pump Fuel Line
1 - Fuel Line
2 - Retaining Clamps3 - Dosing Pump
4 - Heater Unit Air Intake Pipe
24 - 110 DIESEL SUPPLEMENTAL HEATER - DCHA - EXPORTRS
FUEL LINE (Continued)
ProCarManuals.com

NOTE: Do not activate the Dosing Pump Prime
more than one time. This will put excess fuel in the
DCHA Heater Module an cause smoke to emit from
the DCHA exhaust pipe when heater activation
occurs.
NOTE: A clicking noise heard coming from the Dos-
ing Pump indicates that the pump is operational.
(7) With the DRBIIItin Cabin Heater, select Sys-
tem 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 DRBIIItkey pad to exit the Dosing Pump Prime.
The Dosing Pump priming procedure is now com-
plete.
HEATER UNIT
REMOVAL
WARNING: ALLOW THE DCHA TO COOL BEFORE
PERFORMING A COMPONENT INSPECTION/REPAIR
OR REPLACEMENT. FAILURE TO FOLLOW THESE
INSTRUCTIONS MAY RESULT IN PERSONAL
INJURY.
WARNING: ALLOW THE EXHAUST SYSTEM TO
COOL BEFORE PERFORMING A COMPONENT
INSPECTION/REPAIR OR REPLACEMENT. FAILURE
TO FOLLOW THESE INSTRUCTION MAY RESULT IN
PERSONAL INJURY.
(1) Elevate the vehicle on a hoist/lift taking note of
heater exhaust tube flexible section.
(2) Drain 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 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 cross member at two locations.
(6) Disconnect the electrical connector from the
body harness near the toe board cross member and
rail.
(7) Remove the wiring harness from the toe board
cross member(Refer to 24 - HEATING & AIR CON-
DITIONING/CABIN HEATER/HEATER UNIT -
REMOVAL).
(8) Open the fuel fill cap. Disconnect the rubber
fuel hose between the body tube assembly and thefuel 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.
(9) Loosen the two M8 fasteners at the rail. Take
care to notice that the exhaust tube bracket tab is on
top of the heater bracket and that there are (2)
spacer washers installed between the rubber grom-
mets.
(10) Remove the heater exhaust tube flex section
from the exhaust tube by loosening the M6 bolt of
the clamp assembly. Remove the hose from the
exhaust tube. Removal of the rail tube assembly may
aid in this service operation.(Refer to 24 - HEATING
& AIR CONDITIONING/CABIN HEATER/EXHAUST
TUBE - REMOVAL).
(11) Remove seat hex nut at the heater mounting
flange to cross member.
(12) Loosen the remaining M6 and M8 fasteners
which mount the exhaust tube assembly to the vehi-
cle.
(a) Install a suitable cabin heater support device
under the cabin heater and secure the cabin heater
to the device.
(13) Loosen the remaining three M6 fasteners to
the cross members.
(14) Remove the loosened fasteners that support
the heater while supporting the weight of the heater.
(15) Swing the unit mounting bracket from
between the exhaust bracket and rail mounting loca-
tion. Drain any residual coolant from the heater unit.
(16) Lower the cabin heater and remove from the
supporting device and place on a suitable work area.
INSTALLATION
(1) Install the unit mounting bracket between the
exhaust bracket and the rail mounting location.
(2) Install the fasteners that support the heater
while supporting the weight of the heater.
(3) Install the three M6 fasteners to the cross
members. Tighten the M6 fasteners to 7 Nm (5 ft.
lbs.).
(4) Position the two spacer washers between the
body and the rubber grommets for the two M8
mounting points on the rail.
(5) Tighten the remaining M6 fasteners to 7 Nm (5
ft. lbs.) and the M8 fasteners to 23 Nm (17 ft. lbs.)
which mount the exhaust tube assembly to the vehi-
cle.
(6) Install the seat hex nut at the heater mounting
flange to the cross members. Tighten to 60 Nm (44 ft.
lbs.)
(7) Install the heater exhaust tube flex section to
the exhaust tube by tightening the M6 bolt of the
clamp assembly. Install the hose to the exhaust tube.
RSDIESEL SUPPLEMENTAL HEATER - DCHA - EXPORT24 - 111
FUEL LINE (Continued)
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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
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ªBig Slopeº. The PCM checks the oxygen sensor volt-
age in increments of a few milliseconds.
Reduced Output Voltage (Half Cycle)ÐThe
output voltage of the O2S ranges from 0 to 1 volt
(voltages are offset by 2.5 volts on NGC vehicles). A
good sensor can easily generate any output voltage in
this range as it is exposed to different concentrations
of oxygen. To detect a shift in the A/F mixture (lean
or rich), the output voltage has to change beyond a
threshold value. A malfunctioning sensor could have
difficulty changing beyond the threshold value. Each
time the voltage signal surpasses the threshold, a
counter is incremented by one. This is called the Half
Cycle Counter.
Heater PerformanceÐThe heater is tested by a
separate monitor. Refer to the Oxygen Sensor Heater
Monitor.
OPERATIONÐAs the Oxygen Sensor signal
switches, the PCM monitors the half cycle and big
slope signals from the oxygen sensor. If during the
test neither counter reaches a predetermined value, a
malfunction is entered and Freeze Frame data is
stored. Only one counter reaching its predetermined
value is needed for the monitor to pass.
The Oxygen Sensor Monitor is a two trip monitor
that is tested only once per trip. When the Oxygen
Sensor fails the test in two consecutive trips, the
MIL is illuminated and a DTC is set. The MIL is
extinguished when the Oxygen Sensor monitor
passes in three consecutive trips. The DTC is erased
from memory after 40 consecutive warm-up cycles
without test failure.
Enabling ConditionsÐThe following conditions
must typically be met for the PCM to run the oxygen
sensor monitor:
²Battery voltage
²Engine temperature
²Engine run time
²Engine run time at a predetermined speed
²Engine run time at a predetermined speed and
throttle opening
²Transmission in gear and brake depressed (auto-
matic only)
²Fuel system in Closed Loop
²Long Term Adaptive (within parameters)
²Power Steering Switch in low PSI (no load)
²Engine at idle
²Fuel level above 15%
²Ambient air temperature
²Barometric pressure
²Engine RPM within acceptable range of desired
idle
Pending ConditionsÐThe Task Manager typi-
cally does not run the Oxygen Sensor Monitor if over-
lapping monitors are running or the MIL is
illuminated for any of the following:²Misfire Monitor
²Front Oxygen Sensor and Heater Monitor
²MAP Sensor
²Vehicle Speed Sensor
²Engine Coolant Temperature Sensor
²Throttle Position Sensor
²Engine Controller Self Test Faults
²Cam or Crank Sensor
²Injector and Coil
²Idle Air Control Motor
²EVAP Electrical
²EGR Solenoid Electrical (if equipped)
²Intake/inlet Air Temperature
²5 Volt Feed
ConflictÐThe Task Manager does not run the
Oxygen Sensor Monitor if any of the following condi-
tions are present:
²A/C ON (A/C clutch cycling temporarily sus-
pends monitor)
²Purge flow in progress
²Ethanol content learn is taking place and the
ethanol used once flag is set (if equipped)
SuspendÐThe Task Manager suspends maturing
a fault for the Oxygen Sensor Monitor if any of the
following are present:
²Oxygen Sensor Heater Monitor, Priority 1
²Misfire Monitor, Priority 2
OXYGEN SENSOR HEATER MONITOR
DESCRIPTIONÐIf there is an oxygen sensor
(O2S) DTC as well as a O2S heater DTC, the O2S
fault MUST be repaired first. After the O2S fault is
repaired, verify that the heater circuit is operating
correctly.
The voltage readings taken from the O2S are very
temperature sensitive. The readings are not accurate
below a sensor temperature of 300ÉC. Heating of the
O2S is done to allow the engine controller to shift to
closed loop control as soon as possible. The heating
element used to heat the O2S must be tested to
ensure that it is heating the sensor properly.
The heater element itself is not tested. The sensor
output is used to test the heater by isolating the
effect of the heater element on the O2S output volt-
age from the other effects. The resistance is normally
between 100 ohms and 4.5 megaohms. When oxygen
sensor temperature increases, the resistance in the
internal circuit decreases. The PCM sends a 5 volts
biased signal through the oxygen sensors to ground
this monitoring circuit. As the temperature increases,
resistance decreases and the PCM detects a lower
voltage at the reference signal. Inversely, as the tem-
perature decreases, the resistance increases and the
PCM detects a higher voltage at the reference signal.
The O2S circuit is monitored for a drop in voltage.
RSEMISSIONS CONTROL25-3
EMISSIONS CONTROL (Continued)
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