engine coolant CHRYSLER VOYAGER 2004 Service Manual

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)

(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. 20), (Fig. 21) or (Fig. 22).
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 return 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.
INSTALLATION
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).(1) Using spring tension clamp pliers, compress
and slide the clamp away from the end of the heater
return hose.
(2) Install each hose end by carefully twisting the
hose back and forth while gently pushing it onto the
tube.
(3) Using spring tension clamp pliers, compress
and slide the clamps onto each end of the heater
return hose.
(4) Refill the engine cooling system (Refer to 7 -
COOLING - STANDARD PROCEDURE).
Fig. 20 Heater Return Hose - 2.4L Shown, 2.5L
Typical
1 - ENGINE OUTLET NIPPLE
2 - HEATER INLET HOSE
3 - HEATER CORE OUTLET
4 - HEATER CORE INLET
5 - SCREW
6 - HEATER TUBE
7 - HEATER RETURN HOSE
8 - ENGINE INLET NIPPLE
Fig. 21 Heater Return Hose - 3.3L/3.8L W/O Rear
Heater
1 - ENGINE OUTLET NIPPLE
2 - HEATER CORE OUTLET
3 - HEATER CORE INLET
4 - HEATER RETURN TUBE (TYPICAL)
Fig. 22 HEATER HOSES - 3.3/3.8L With Rear Heater
1 - STUD
2 - HEATER CORE OUTLET
3 - HEATER CORE INLET
4 - TO ENGINE OUTLET NIPPLE
5 - TO UNDERBODY PLUMBING
6 - TO HEATER RETURN TUBE & HOSE
RSPLUMBING - FRONT24-87
HEATER RETURN HOSE (Continued)

(4) Install the two screws that secure the rear A/C
expansion valve to the evaporator tube sealing plate.
Tighten the screws to 11 N´m (97 in. lbs.).
(5) Install the rear evaporator line extension onto
the expansion valve (Refer to 24 - HEATING & AIR
CONDITIONING/PLUMBING - REAR/EVAPORA-
TOR - INSTALLATION - EVAPORATOR LINE
EXTENSION).
(6) Install the foam insulator wrap over the rear
expansion valve.
(7) Install the rear HVAC housing (Refer to 24 -
HEATING & AIR CONDITIONING/DISTRIBUTION/
HVAC HOUSING - INSTALLATION).
(8) Run the HVAC Cooldown Test to verify proper
operation.
HEATER CORE
DESCRIPTION
The rear heater core is located near the front of
the rear HVAC housing, behind the right rear wheel
house. It is a heat exchanger made of rows of tubes
and fins. One end of the core is fitted with a molded
plastic tank that includes integral heater core inlet
and outlet nipples. The rear heater core can be ser-
viced without removing the rear HVAC housing from
the vehicle.
OPERATION
Engine coolant is circulated through underbody
heater hoses to the rear heater core at all times. As
the coolant flows through the rear heater core, heat
removed from the engine is transferred to the heater
core fins and tubes. Air directed through the heater
core picks up the heat from the heater core fins. The
rear blend door allows control of the rear heater out-
put air temperature by controlling how much of the
air flowing through the rear HVAC housing is
directed through the heater core.
The rear heater core cannot be repaired and, if
faulty or damaged, it must be replaced.
STANDARD PROCEDURE - REAR HEATER
CORE FILLING
In its final installed position, the rear heater core
is positioned higher than the radiator fill cap. There-
fore, when the cooling system is drained and refilled,
gravity will not refill the heater core with coolant to
the proper level. This may result in two problems:1.
Insufficient coolant level in the engine cooling sys-
tem, which may result in engine overheating.2.Air
entrapped within the rear heater core, which may
result in insufficient rear heater performance. There
are two methods that may be employed to prevent
these problems:1.Pre-filling of the rear heater core.2.Thermal cycling of the engine cooling system. Fol-
lowing are descriptions of both prevention methods,
as well as a method to verify rear heater perfor-
mance.
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 PLUMBING).
PRE-FILLING
If the rear heater core or the rear HVAC 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 reconnecting the
heater hoses to the heater core hose fittings.
(1) The heater core should be installed in the rear
HVAC housing, and the rear HVAC housing should
be installed in the vehicle.
(2) Take the proper precautions to protect the car-
peting below the rear heater core from spilled engine
coolant and have absorbent toweling readily avail-
able to mop up any spills.
(3) Insert the small end of an appropriate funnel
into the upper hose fitting of the heater core (Fig. 4).
(4) Carefully pour the proper pre-mixed engine
coolant solution into the rear heater core through a
funnel until coolant begins to appear at the lower
hose fitting of the heater core.
(5) Use absorbent toweling to clean up any engine
coolant spills from the preceding operation.
(6) Reconnect the heater hoses to the rear heater
core (Refer to 24 - HEATING & AIR CONDITION-
ING/PLUMBING - REAR/HEATER HOSE - INSTAL-
LATION).
Fig. 4 Pre-Filling Heater Core - Typical
1 - REAR HEATER CORE
RSPLUMBING - REAR24 - 101
A/C EXPANSION VALVE (Continued)

(7) Refill the engine cooling system (Refer to 7 -
COOLING - STANDARD PROCEDURE - COOLING
SYSTEM REFILL).
THERMAL CYCLING
If the rear heater core was emptied and was not
pre-filled, it will be necessary to thermal cycle the
vehicle at least two times to ensure that the rear
heater core is properly filled.
(1) Refill the engine cooling system (Refer to 7 -
COOLING - STANDARD PROCEDURE - COOLING
SYSTEM REFILL).
(2) Start the engine and allow it to operate until
the thermostat opens.
(3) Turn the engine off and allow it to cool.
(4) With the engine cold and not running, check
and top off the engine coolant level as necessary
(Refer to 7 - COOLING - STANDARD PROCEDURE
- COOLANT LEVEL CHECK) and (Refer to 7 -
COOLING - STANDARD PROCEDURE - COOLANT
- ADDING).
(5) Start the engine and allow it to operate until
the thermostat opens again.
(6) Turn the engine off and allow it to cool down
again.
(7) With the engine cold and not running, check
and top off the engine coolant level as necessary
(Refer to 7 - COOLING - STANDARD PROCEDURE
- COOLANT LEVEL CHECK) and (Refer to 7 -
COOLING - STANDARD PROCEDURE - COOLANT
- ADDING).
(8) Check the performance of the rear heater.
Refer to REAR HEATER PERFORMANCE CHECK.
REAR HEATER PERFORMANCE CHECK
Successful completion of the rear heater perfor-
mance check will confirm that the rear heater core is
properly filled with engine coolant. If the check is not
successful, either there is still air trapped in the rear
heater core or the rear heater plumbing is restricted.
This check should be performed with the vehicle in a
shop where the ambient temperature is about 21É C
(70É F).
(1) Start the engine and allow it to idle until it
warms up to normal operating temperature.
(2) Adjust the heater-A/C controls so that the front
heater is turned Off, the rear heater is set for full
Heat, and the rear blower motor is at its highest
speed setting.
(3) Use an accurate test thermometer to measure
the temperature of the air being discharged from the
rear heater outlet located at the base of the right
C-pillar.
(4) Proper discharge air temperature readings
should be from 57É to 63É C (135É to 145É F).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
FRONT - WARNING - HEATER PLUMBING).
(1) Drain the engine cooling system (Refer to 7 -
COOLING - STANDARD PROCEDURE - COOLING
SYSTEM DRAIN).
(2) 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 - REMOVAL).
(3) Remove the rear heater distribution duct from
the right quarter inner panel (Refer to 24 - HEAT-
ING & AIR CONDITIONING/DISTRIBUTION -
REAR/REAR HEATER DISTRIBUTION DUCT -
REMOVAL).
(4) Remove the screw that secures the back of the
rear HVAC housing to the right D-pillar.
(5) Remove the screw that secures the front of the
rear HVAC housing to the right quarter inner panel.
(6) Take the proper precautions to protect the car-
peting below the rear heater core from spilled engine
coolant and have absorbent toweling readily avail-
able to mop up any spills.
(7) Disconnect the heater hoses at the rear heater
core (Refer to 24 - HEATING & AIR CONDITION-
ING/PLUMBING - REAR/HEATER HOSE -
REMOVAL).
(8) Install plugs in, or tape over the opened heater
core fittings and both heater hoses (Fig. 5).
Fig. 5 Rear Heater Core
1 - REAR HVAC HOUSING OUTLET
2 - REAR HVAC UNIT HOUSING
3 - LATCH (4)
4 - REAR HEATER CORE
5 - RIGHT REAR WHEEL HOUSE
6 - REAR HEATER HOSES
24 - 102 PLUMBING - REARRS
HEATER CORE (Continued)

(9) Use absorbent toweling to clean up any engine
coolant spills from the preceding operation.
(10) Release the four latch tabs that secure the
heater core into the rear HVAC housing.
(11) Carefully pull the heater core straight out of
the rear HVAC housing.
(12) Use absorbent toweling to clean up any
engine coolant spills from the preceding operation.
INSTALLATION
NOTE: If the rear heater core or the rear HVAC
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
HVAC 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 HVAC housing
are fully engaged.
(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 the screw that secures the front of the
rear HVAC housing to the right quarter inner panel.
Tighten the screw to 11 N´m (97 in. lbs.).
(6) Install the screw that secures the back of the
rear HVAC housing to the right D-pillar. Tighten the
screw to 11 N´m (97 in. lbs.).
(7) Install the rear heater distribution duct (Refer
to 24 - HEATING & AIR CONDITIONING/DISTRI-
BUTION - REAR/REAR HEATER DISTRIBUTION
DUCT - INSTALLATION).
(8) Install the right quarter trim panel and right
D-pillar trim panel (Refer to 23 - BODY/INTERIOR/
QUARTER TRIM PANEL - INSTALLATION).
(9) Refill the engine cooling system (Refer to 7 -
COOLING - STANDARD PROCEDURE - COOLING
SYSTEM REFILL).
HEATER HOSES
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).
(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.
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.
(3) Disconnect the front underbody heater inlet
and return hose by carefully twisting the hoses back
and forth on the underbody tubes, while gently pull-
ing them away from the end of the tubes (Fig. 6).
(4) If necessary, carefully cut the hose ends and
peel the hoses off of the tubes.
NOTE:
Replacement of the heater hoses will be required if
the hose ends are cut for removal.
Fig. 6 Underbody Heater Hose Connections - Front
1 - SUCTION LINE EXTENSION
2 - LIQUID LINE EXTENSION
3 - RETAINER STRAP (3)
4 - HEATER TUBES
5 - UNDERBODY LINES
RSPLUMBING - REAR24 - 103
HEATER CORE (Continued)

INSTALLATION
(1) Install the front underbody heater inlet and
return hoses by carefully twisting the hoses back and
forth on the underbody tubes, while gently pushing
them onto the end of the tubes.
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) 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.
(3) Refill the engine cooling system (Refer to 7 -
COOLING - STANDARD PROCEDURE - COOLING
SYSTEM REFILL).
LIQUID LINE
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 -
FRONT - WARNING - A/C PLUMBING) and (Refer to
24 - HEATING & AIR CONDITIONING/PLUMBING -
FRONT - CAUTION - A/C PLUMBING).
NOTE: On models equipped with the optional rear
A/C system, the rear section of the front air condi-
tioner liquid line also includes a liquid line hose
and tube extension that connects the front liquid
line to the underbody liquid line for the rear A/C
system.
(1) Recover the refrigerant from the refrigerant
system (Refer to 24 - HEATING & AIR CONDITION-
ING/PLUMBING - FRONT/REFRIGERANT - STAN-
DARD PROCEDURE - REFRIGERANT
RECOVERY).
(2) Disconnect and isolate the battery negative
cable.
(3) Remove the air cleaner housing from 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 A/C pressure transducer (Refer to
24 - HEATING & AIR CONDITIONING/CONTROLS
- FRONT/A/C PRESSURE TRANSDUCER -
REMOVAL).(6) If equipped, remove the nut that secures the
A/C ground strap to the weld stud on the top of the
right front strut tower (Fig. 7).
(7) If equipped, remove the A/C ground strap eye-
let terminal connector from the weld stud.
(8) Remove the bolt that secures the liquid line
rear section fitting to the top of the receiver/drier.
(9) Disconnect the liquid line fitting from the
receiver/drier outlet port.
(10) Remove the O-ring seal from the liquid line
fitting and discard.
(11) Install plugs in, or tape over the opened liquid
line fitting and the receiver/drier outlet port.
(12) Remove the nut that secures the suction line
and liquid line fittings to the expansion valve.
(13) Disconnect the suction line and liquid line fit-
tings from the expansion valve.
(14) Remove the seals from the suction line and
liquid line fittings and discard.
(15) Install plugs in, or tape over the opened suc-
tion line and liquid line fittings and both expansion
valve ports.
(16) Raise and support the vehicle.
Fig. 7 Liquid Line
1 - A/C GROUND STRAP (IF EQUIPPED)
2 - NUT (IF EQUIPPED)
3 - WELD STUD (IF EQUIPPED)
4 - A/C PRESSURE TRANSDUCER
5 - WELD STUD (2)
6 - EXPANSION VALVE
7 - FRONT LIQUID LINE REAR SECTION
8 - LIQUID LINE EXTENSION (REAR A/C ONLY)
9 - NUT (2)
10 - RECEIVER/DRIER
11 - ROUTING CLIP
12 - FRONT LIQUID LINE FRONT SECTION
24 - 104 PLUMBING - REARRS
HEATER HOSES (Continued)

(18) Install plugs in, or tape over the opened suc-
tion line fittings.
(19) Lower the vehicle.
(20) Remove the suction line from the engine com-
partment.
INSTALLATION
(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 the nut that secures the suction line
and liquid line fittings to the front 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 receiver/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 the nut that secures the suction line
fitting to the A/C 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) Raise and support the vehicle.
(15) Remove the tape or plugs from the suction
line extension fitting and the underbody suction line
fitting.(16) Lubricate a new rubber O-ring seal with clean
refrigerant oil and install it on the underbody suction
line fitting.
(17) Reconnect the suction line extension fitting to
the underbody suction line fitting. Tighten the fitting
to 23 N´m (17 ft. lbs.).
(18) Install a new tie strap just forward of the con-
nections between the underbody plumbing and the
engine compartment plumbing for the rear heater
and air conditioner.
(19) Lower the vehicle.
(20) Evacuate the refrigerant system (Refer to 24 -
HEATING & AIR CONDITIONING/PLUMBING -
FRONT/REFRIGERANT - STANDARD PROCE-
DURE - REFRIGERANT SYSTEM EVACUATE).
(21) Charge the refrigerant system (Refer to 24 -
HEATING & AIR CONDITIONING/PLUMBING -
FRONT/REFRIGERANT - STANDARD PROCE-
DURE - REFRIGERANT SYSTEM CHARGE).
UNDERBODY LINES
DESCRIPTION
The underbody heater-A/C plumbing is used only
on models with the optional rear heater-A/C system
(Fig. 11). The underbody suction line, liquid line, and
heater tubes can each be serviced separately.
OPERATION
The rear heater and A/C lines are all serviced as
individual pieces. When disconnecting any line or
block ensure that the area around it is clean of any
contaminations that can get in to the system (Fig.
12), (Fig. 13), (Fig. 15), (Fig. 14) and (Fig. 16).
Any kinks or sharp bends in the rear heater-A/C
unit plumbing will reduce the capacity of the entire
heating and air conditioning system. Kinks and
sharp bends reduce the system flow. High pressures
are produced in the refrigerant system when the air
conditioning compressor is operating. High tempera-
ture coolant is present in the heater plumbing when
the engine is operating. Extreme care must be exer-
cised o make sure that each of the plumbing connec-
tions is pressure-tight and leak free.
RSPLUMBING - REAR24 - 107
SUCTION LINE (Continued)

REMOVAL
REMOVAL - UNDERBODY HEATER TUBES
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).
(1) Drain the engine cooling system (Refer to 7 -
COOLING - STANDARD PROCEDURE - COOLING
SYSTEM DRAIN).
(2) Raise and support vehicle.
(3) Disconnect the underbody heater tubes at the
rear of the vehicle by releasing the insert in the rear
underbody heater tube quick connect fittings (Fig.17) and carefully pulling downward on the inlet and
return tubes.
(4) Remove the three retaining straps that secure
the rear heater underbody tubes to the vehicle under-
body (Fig. 18).
(5) Lower the rear of the underbody heater tubes
and drain any residual coolant from the tubes into a
suitable container.
(6) Using spring tension clamp pliers, compress
and slide the clamps off of the rubber hoses at the
front of the underbody heater tubes.
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.
(7) Disconnect the front underbody heater inlet
and return hoses by carefully twisting the hoses back
and forth on the underbody tubes, while gently pull-
ing them away from the end of the tubes.
(8) If necessary, carefully cut the hose ends and
peel the hoses off of the tubes.
NOTE:
Replacement of the heater hoses will be required if
the hose ends are cut for removal.
(9) Remove the underbody heater tubes from the
vehicle.
Fig. 15 Rear heater hose quick connects
1 - INSERT
2 - QUICK CONNECT FITTING
3 - COMPRESS INSERT FOR REMOVAL
Fig. 16 Rear A/C Block Connection
1 - CLEAN AREA AROUND BLOCK BEFORE REMOVAL
Fig. 17 Underbody Heater Tube Quick Connect
Fittings
1 - INSERT
2 - QUICK CONNECT FITTING
3 - COMPRESS INSERT FOR REMOVAL
RSPLUMBING - REAR24 - 109
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)

CABIN HEATER
TABLE OF CONTENTS
page page
CABIN HEATER
DESCRIPTION........................112
OPERATION
OPERATION - MANUAL TEMPERATURE
CONTROL SYSTEM...................112
OPERATION - AUTOMATIC TEMPERATURE
CONTROL SYSTEM...................112
DIAGNOSIS AND TESTING - DIESEL
SUPPLEMENTAL CABIN HEATER........113
AIR INTAKE PIPE
REMOVAL............................113
INSTALLATION........................114
EXHAUST TUBE
REMOVAL............................114
INSTALLATION........................115FUEL DOSING PUMP
DESCRIPTION........................115
OPERATION..........................115
REMOVAL............................115
INSTALLATION........................116
FUEL LINE
STANDARD PROCEDURE - CLEANING.....117
REMOVAL............................117
INSTALLATION........................118
HEATER UNIT
REMOVAL............................118
INSTALLATION........................119
SUPPLEMENTAL DIESEL HEATER WIRING
REMOVAL............................119
INSTALLATION........................119
CABIN HEATER
DESCRIPTION
Vehicles equipped with the diesel engine are also
equipped with a supplemental cabin heater. This
cabin heater is mounted under the vehicle and oper-
ates 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 cabin heater and then to the front
heater core. This provides additional heat to the pas-
senger compartment. The supplemental cabin heater
system is interfaced to the vehicles on-board com-
puter systems and DRBIIItdiagnostics.
The supplemental cabin heater has an electronic
control module that monitors the heat output of the
heater. The cabin heater operates at full load (5 kW),
half load or idle mode (no additional heat) depending
on engine coolant temperature.
OPERATION
OPERATION - MANUAL TEMPERATURE
CONTROL SYSTEM
The supplemental cabin heater is activated via the
temperature slide control or knob on the A/C-heater
control when equipped with the manual temperature
control (MTC) system. If the slide control or knob is
moved to or above the upper set point the cabin
heater is activated. The cabin heater can operate in a
full or partial load range as well as an idle mode alldependent on the engine coolant temperature. The
cabin heater will also turn off if the A/C-heater tem-
perature control is lowered to less than the lower set
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).
OPERATION - AUTOMATIC TEMPERATURE
CONTROL SYSTEM
The automatic temperature control (ATC) system
will activate the supplemental cabin heater based on
engine coolant temperature and interior component
settings. The cabin heater can operate in a full or
partial load range as well as an idle mode all depen-
dent on the engine coolant temperature. The cabin
heater will also turn off if the A/C-heater tempera-
ture control is lowered to less than the lower set
24 - 112 CABIN HEATERRS