REMOVAL - UNDERBODY REFRIGERANT LINES
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 CONDITION-
ING/PLUMBING - FRONT/REFRIGERANT - STAN-
DARD PROCEDURE - REFRIGERANT
RECOVERY).
(2) Hoist and support vehicle.
(3) Remove the underbody refrigerant lines from
the three retaining straps that secure the rear under-
body refrigerant lines to the vehicle underbody (Fig.
19).
(4) Remove the underbody refrigerant lines from
the two rear retaining clamps, behind rear wheel.
(5) Disconnect the front liquid line extension fit-
ting from the underbody liquid line fitting for the
rear air conditioner.
(6) Remove the O-ring seal from the underbody liq-
uid line fitting and discard.
(7) Install plugs in, or tape over the opened liquid
line fittings.
(8) Disconnect the front suction line extension fit-
ting from the underbody suction line fitting for the
rear air conditioner.
(9) Remove the O-ring seal from the underbody
suction line fitting and discard.(10) Install plugs in, or tape over the opened suc-
tion line fittings.
(11) Disconnect the underbody refrigerant line
sealing plate from the rear evaporator extension line
sealing plate that extends through the rear floor
panel behind the right rear wheel housing (Fig. 20).
(12) Remove the O-ring seal from the underbody
refrigerant line fittings and discard.
(13) Install plugs in, or tape over the opened
underbody refrigerant line fittings and the rear evap-
orator extension line sealing plate ports.
(14) Separate the ABS harness from the flex hose
clamps.
(15) Remove the underbody refrigerant lines from
the vehicle.
Fig. 18 Underbody Connections
1 - SUCTION LINE EXTENSION
2 - LIQUID LINE EXTENSION
3 - RETAINER STRAP (3)
4 - HEATER TUBES
5 - UNDERBODY REFRIGERANT LINES
Fig. 19 Underbody Refrigerant Line Connections
1 - SUCTION LINE EXTENSION
2 - LIQUID LINE EXTENSION
3 - RETAINER STRAP (3)
4 - HEATER TUBES
5 - UNDERBODY REFRIGERANT LINES
Fig. 20 Underbody Refrigerant Line Sealing Plate
1 - REFRIGERANT LINE SEALING PLATE
24 - 110 PLUMBING - REARRS
UNDERBODY LINES (Continued)
(16) Place the underbody refrigerant lines on a
workbench and remove the nylon wedge securing the
underbody refrigerant lines to the underbody refrig-
erant line sealing plate (Fig. 21).
INSTALLATION
INSTALLATION - REAR HEATER LINES
(1) Position the rear heater underbody tubes to the
vehicle.
CAUTION:
DO NOT apply excessive pressure on heater tubes
or connections when removing heater hoses.
Excessive pressure may damage or deform the
tubes, causing an engine coolant leak.
(2) Connect the front underbody heater inlet and
return hose by carefully twisting the hoses back and
forth on the underbody tubes, while gently pushing
them onto the end of the tubes.
(3) Using spring tension clamp pliers, compress
and slide the clamps that secure each end of the
heater hose over the tubes. Release the clamp when
it is over the tube.
(4) Install the three retaining straps that secure
the rear heater underbody tubes to the vehicle under-
body.
(5) Connect the rear underbody heater tube quick
connections to the rear heater core extension tubes.
(6) Lower the vehicle.
(7) Refill the engine cooling system (Refer to 7 -
COOLING - STANDARD PROCEDURE - COOLING
SYSTEM REFILL).(8) Lower vehicle.
(9) Fill cooling system (Refer to 7 - COOLING -
STANDARD PROCEDURE).
INSTALLATION - UNDERBODY REFRIGERANT
LINES
(1) Install the nylon wedges that secure the under-
body refrigerant lines to the underbody refrigerant
line sealing plate.
(2) Position the underbody refrigerant lines to the
vehicle underbody.
(3) Install the ABS harness into the flex hose
clamps.
(4) Remove the tape or plugs from the underbody
liquid line and suction line fittings and both ports in
the rear evaporator extension line sealing plate that
extends through the rear floor panel behind the right
rear wheel housing.
(5) Lubricate new rubber O-ring seals with clean
refrigerant oil and install them on the liquid line and
suction line fittings.
(6) Reconnect the underbody refrigerant line seal-
ing plate to the evaporator extension line sealing
plate.
(7) Install the bolt that secures the underbody
refrigerant line sealing plate to the evaporator exten-
sion line sealing plate. Tighten the bolt to 23 N´m (17
ft. lbs.).
(8) Remove the tape or plugs from the suction line
extension fitting and the underbody suction line fit-
ting.
(9) Lubricate a new rubber O-ring seal with clean
refrigerant oil and install it on the underbody suction
line fitting.
(10) Reconnect the suction line extension fitting to
the underbody suction line fitting. Tighten the fitting
to 23 N´m (17 ft. lbs.).
(11) Remove the tape or plugs from the liquid line
rear section extension fitting and the underbody liq-
uid line fitting.
(12) Lubricate a new rubber O-ring seal with clean
refrigerant oil and install it on the underbody liquid
line fitting.
(13) Reconnect the liquid line rear section exten-
sion fitting to the underbody liquid line fitting.
Tighten the fittings to 23 N´m (17 ft. lbs.).
(14) Lower the vehicle.
(15) Evacuate the refrigerant system (Refer to 24 -
HEATING & AIR CONDITIONING/PLUMBING -
FRONT/REFRIGERANT - STANDARD PROCE-
DURE - REFRIGERANT SYSTEM EVACUATE).
(16) Charge the refrigerant system (Refer to 24 -
HEATING & AIR CONDITIONING/PLUMBING -
FRONT/REFRIGERANT - STANDARD PROCE-
DURE - REFRIGERANT SYSTEM CHARGE).
Fig. 21 Underbody Line Wedges
1 - O-RING (2)
2 - LIQUID LINE
3 - NYLON WEDGE (2)
4 - SEALING PLATE
5 - VISE
6 - SUCTION LINE
RSPLUMBING - REAR24 - 111
UNDERBODY LINES (Continued)
point. The cabin heater can take up to three minutes
to completely shut down when either the heater tem-
perature is set below the lower set point or the vehi-
cle ignition is shut down.
NOTE: Do not apply a strong vacuum source such
as a garage ventilation system directly on the sup-
plemental cabin heater exhaust line. Too strong of a
vacuum can prevent the supplemental cabin heater
from starting. If required, place the vacuum source
at least 75 mm (3 in.) away from the exhaust line.
The supplemental cabin heater only operates when
the engine is running, the mileage exceeds 8 kilome-ter (5 mph) and the fuel tank volume exceeds 1/8 of a
tank. The supplemental heater control module moni-
tors blower speed and combustion during its start-up.
The cabin heater should operate if the coolant tem-
perature is below 40É C (104É F).
DIAGNOSIS AND TESTING - DIESEL
SUPPLEMENTAL CABIN HEATER
Refer to the Symptoms Diagnosis table for basic
checks of the diesel fueled supplemental cabin heater.
SYMPTOMS DIAGNOSIS
Symptom Possible Causes
Smell of diesel fuel. Check cabin 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 cabin heater and re-inspect.
Inspect the exhaust tube and cabin heater for the presence of external
fuel. If presence of external fuel is observed on the heater unit or in the
exhaust tube or after draining and testing. Remove the cabin heater
from vehicle and repair or replace components as required.
Heater does not achieve full load
operation.Check cabin heater operation with DRBIIITscan tool and replace
components as required.
Continuous white smoke from heater
exhaust during combustion operation.Check cabin heater operation with DRBIIITscan tool and replace
components as required. White smoke is typical in extreme weather
conditions.
Heater can not be switched off. Check cabin heater operation with DRBIIITscan tool and replace
components as required.
Heater does not operate. Diagnosis cabin heater control module using the DRBIIITscan tool 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 cabin heater should be inspected and
components should be replaced as required.
Loss of fuel (dripping). Check cabin heater system integration in vehicles fuel system. Check
fuel line connection for leakage. If OK there is an internal leak and
cabin heater should be inspected and replaced as required.
AIR INTAKE PIPE
REMOVAL
NOTE: The air intake tube for the supplemental
cabin heater is part of an assembly that includes
the heater cooling intake and return pipes. If the
cabin heater air intake tube requires removal or
replacement the entire cabin heater assembly will
require removal or replacement.(1) Drain the engine cooling system (Refer to 7 -
COOLING - STANDARD PROCEDURE).
(2) Remove clamps from the cabin heater tubes at
the lower heater port and the lower EGR connector
which are located under the hood.
(3) Remove the retaining clamp at the cabin
heater air intake muffler connection (Refer to 24 -
HEATING & AIR CONDITIONING/CABIN HEAT-
ER/INLET MUFFLER - REMOVAL).
(4) Remove the clamp at the flexible tube to steel
tube connection (Fig. 1).
RSCABIN HEATER24 - 113
CABIN HEATER (Continued)
INSTALLATION
(1) Install the flexible exhaust pipe to the cabin
heater. Tighten the mounting clamp securely.
(2) Position the steel exhaust pipe to the flexible
exhaust. Tighten the mounting clamp securely.
(3) Loosely install the three exhaust pipe screws
and adjust pipe placement as required. Tighten the
screws securely.
(4) Install the clamp that secures the steel exhaust
pipe to the flexible exhaust pipe. Tighten the clamp
securely.
(5) Check exhaust end placement of the exhaust
pipe and make any final adjustments.
(6) Lower the vehicle.
FUEL DOSING PUMP
DESCRIPTION
The dosing pump is a combined delivery, dosing
and shut-off system for the fuel supply to the supple-
mental cabin heater from the vehicle fuel tank.
OPERATION
The dosing pump is an electrically operated pump
that receives its operation instructions from the sup-
plemental cabin heater control module. The pump
supplies diesel fuel from the vehicle fuel tank to the
cabin heater.
REMOVAL
NOTE: The dosing pump is serviceable without
removing the component from the vehicle.
(1) Disconnect the rubber hose at the fuel line to
heater fuel pump. Leave the rubber hose on the fuel
line (Refer to 24 - HEATING & AIR CONDITION-
ING/CABIN HEATER/FUEL LINE - REMOVAL)
(Fig. 4).
(2) Disconnect the fuel line between the dosing
pump and the cabin heater unit.
NOTE: Position and retain the heater fuel line to
prevent fuel leakage while servicing the dosing
pump.
Fig. 3 Cabin Heater Exhaust System
1 - MOUNTING SCREWS (3)
2 - STEEL HEATER EXHAUST PIPE
3 - EXHAUST CLAMP (2)4 - FLEXIBLE HEATER EXHAUST PIPE
5 - CABIN HEATER AND SHIELD
6 - EXHAUST PIPE MOUNTING CLIPS (3) (IF EQUIPPED)
RSCABIN HEATER24 - 115
EXHAUST TUBE (Continued)
NOTE: Utilize an approved fuel storage container to
catch any residual fuel.
(3) Disconnect the wiring harness connector to the
fuel pump by depressing the integral spring and pull-
ing the connector away from the pump.
(4) Remove the dosing pump from the rubber iso-
lator.
INSTALLATION
(1) Install the dosing pump onto the rubber isola-
tor.
(2) Connect the fuel lines to the dosing pump and
the cabin heater unit.NOTE: The connectors should point towards the
cabin heater fuel line.
(3) Use aviation style clamps to attach the hose to
the fuel pump nipples (Refer to 24 - HEATING &
AIR CONDITIONING/CABIN HEATER/FUEL LINE
- INSTALLATION).
(4) Connect the wire harness connector to the fuel
pump by depressing the integral spring and pushing
the connector towards the dosing pump. Pull the con-
nector towards the cabin heater to verify the instal-
lation.
(5) Verify function of the supplemental cabin
heater.
Fig. 4 Cabin Heater Dosing Pump Fuel Line
1 - FUEL LINE
2 - RETAINING CLAMP3 - DOSING PUMP
4 - HEATER AIR INTAKE PIPE
24 - 116 CABIN HEATERRS
FUEL DOSING PUMP (Continued)
FUEL LINE
STANDARD PROCEDURE - CLEANING
(1) Remove the cabin heater fuel line (Refer to 24 -
HEATING & AIR CONDITIONING/CABIN HEAT-
ER/FUEL LINE - REMOVAL).
(2) With the cabin heater fuel line removed from
the vehicle, place a shop cloth on the fuel tank end of
the fuel line to catch any residue, then apply a small
amount of air pressure to the other end of the fuel
line.
(3) Check to see if air pressure is coming from the
tank end of the line. If pressure is flowing unre-
stricted the line is clean.
(4) If the fuel line shows any signs of being
restricted after air pressure is applied, the fuel line
should be replaced.
(5) Install the cabin heater fuel line (Refer to 24 -
HEATING & AIR CONDITIONING/CABIN HEAT-
ER/FUEL LINE - INSTALLATION).
(6) Verify function of the cabin heater.
REMOVAL
(1) Raise and support the vehicle. Take note of the
location of the flexible section of the cabin heater
exhaust tube.NOTE: Have an approved fuel holding device ready
to capture any diesel fuel that drains from the fuel
line or cabin heater unit.
(2) Remove clamps on dosing pump end of fuel line
and separate line from the pump (Fig. 5).
(3) Remove clamp from the fuel line at the fuel
tank connection and separate the line from the tank.
(4) Remove any retaining clips and remove the
fuel line from vehicle.
Fig. 5 Cabin Heater Dosing Pump Fuel Line
1 - FUEL LINE
2 - RETAINING CLAMP3 - DOSING PUMP
4 - HEATER AIR INTAKE PIPE
RSCABIN HEATER24 - 117
(9) Loosen the two 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 two spacer
washers installed between the rubber grommets.
(10) Remove the flexible section of the cabin
heater exhaust tube from the exhaust tube by loos-
ening the clamp. 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 crossmember.
(12) Loosen the remaining fasteners which mount
the exhaust tube assembly to the vehicle.
(a) Install a suitable support device under the
cabin heater and secure the cabin heater to the
support.
(13) Loosen the remaining three fasteners to the
crossmembers.
(14) Remove the loosened fasteners that support
the cabin heater while supporting the weight of the
heater.
(15) Swing the cabin heater mounting bracket
from between the exhaust bracket and rail mounting
location. Drain any residual coolant from the cabin
heater.
(16) Remove the cabin heater from the vehicle.
INSTALLATION
(1) Install the cabin heater mounting bracket
between the exhaust bracket and the rail mounting
location.
(2) Support the cabin heater and install the fasten-
ers that secure the cabin heater to the mounting
bracket.
(3) Install the three fasteners to the crossmem-
bers. Tighten the M6 fasteners to 7 N´m (62 in. lbs.).
(4) Position the two spacer washers between the
body and the rubber grommets for the two mounting
points on the rail.
(5) Tighten the remaining M6 fasteners to 7 N´m
(62 in. lbs.) and the M8 fasteners to 23 N´m (17 ft.
lbs.) which mount the exhaust tube assembly to the
vehicle.
(6) Install the seat hex nut at the heater mounting
flange to the crossmembers. Tighten the nut to 60
N´m (44 ft. lbs.)
(7) Install the flexible section of the cabin heater
exhaust tube to the exhaust tube. Tighten the M6
bolt of the clamp securley. Install the hose to the
exhaust tube.
(8) Tighten the two M8 fasteners at the rail to 23
N´m (17 ft. lbs.). Taking care so that the exhaust
tube bracket tab is on the top of the heater bracket.(9) Install the wiring harness (Refer to 24 - HEAT-
ING & AIR CONDITIONING/CABIN HEATER/
HEATER UNIT - INSTALLATION).
(10) Tighten the hose and tube assembly to the
toe-board crossmember at two locations.
(11) Install the second hose to the underbody hose
and tube assembly.
(12) Connect the rubber fuel hose between the
body tube assembly and the fuel pump nipple at the
body tube joint. Close the fuel fill cap.
(13) Remove the cabin heater support device from
under the vehicle.
(14) Lower the vehicle.
(15) Fill the engine cooling system (Refer to 7 -
COOLING - STANDARD PROCEDURE).
(16) Verify function of the cabin heater.
SUPPLEMENTAL DIESEL
HEATER WIRING
REMOVAL
(1) Elevate vehicle on a lift taking note of the
exhaust tube flexible section.
(2) Unplug connector from vehicle wiring harness
to cabin heater harness.
(3) Unplug connector from cabin heater harness to
dosing pump connector.
(4) Unplug two connectors from cabin heater har-
ness to cabin heater controller connectors.
(5) Remove two wiring harness connectors from
underbody.
(6) Remove two wiring harness connectors from
cabin heater shield.
(7) Carefully route the cabin heater harness to the
left side between the cabin heater unit and the cabin
heater shield.
INSTALLATION
(1) Carefully route the cabin heater harness from
the left side of the cabin heater between the cabin
heater unit and the cabin heater shield.
(2) Install the two wiring harness retaining con-
nectors to the cabin heater shield.
(3) Route the wiring harness along the underside
of the vehicle and install the two wiring harness
retaining connectors.
(4) Plug the two connectors from the cabin heater
harness to the cabin heater controller.
(5) Plug the connector to the cabin heater harness
to the dosing pump connector.
(6) Plug the connector from the vehicle wiring har-
ness to the cabin heater harness.
(7) Lower the vehicle.
(8) Verify function of the cabin heater.
RSCABIN HEATER24 - 119
HEATER UNIT (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