2003 CHRYSLER CARAVAN heater

(16) Remove the tape or plugs from the suction
line extension fitting and the underbody suction line
fitting (Fig. 35).
(17) Lubricate a new rubber O-ring seal with clean
refrigerant oil and install it on the underbody suction
line fitting.
(18) Reconnect the suction line extension fitting to
the underbody suction line fitting. Tighten the fit-
tings to 23 N´m (17 ft. lbs.).
(19) 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.
(20) Lower the vehicle.
(21) Evacuate the refrigerant system. (Refer to 24
- HEATING & AIR CONDITIONING/PLUMBING -
FRONT/REFRIGERANT - STANDARD PROCE-
DURE - REFRIGERANT SYSTEM EVACUATE).
(22) Charge the refrigerant system. (Refer to 24 -
HEATING & AIR CONDITIONING/PLUMBING -
FRONT/REFRIGERANT - STANDARD PROCE-
DURE - REFRIGERANT SYSTEM CHARGE).UNDERBODY LINES
DESCRIPTION
The rear heater-A/C unit plumbing is used only on
models with the optional rear heater-A/C unit. The
formed metal rear heater-A/C unit suction line, liquid
line, and heater lines are available for separate ser-
vice replacement. The molded and straight heater
hoses used on the rear heater-A/C unit can be ser-
viced in the vehicle. Refer to Group 7 - Cooling Sys-
tem for the heater hose service procedures.
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. 9),
(Fig. 10), (Fig. 12), (Fig. 11) and (Fig. 13).
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 to make sure that each of the plumbing connec-
tions is pressure-tight and leak free.
Fig. 9 Rear Heater and A/C Lines
1 - HEATER CONNECTION
2 - REAR A/C LINE BLOCK CONNECTION
RSPLUMBING - REAR24 - 103
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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(11) Loosen hose clamps at front of heater lines
and allow them to hang from vehicle.
(12) Remove rear A/C lines from vehicle.
(13) Remove nylon wedge holding lines into rear
block (Fig. 14).INSTALLATION
INSTALLATION - REAR HEATER LINES
(1) Install line into underbody straps.
(2) Install line into front hose and install hose
clamp.
(3) Connect quick fitting at rear of line.
(4) Lower vehicle.
(5) Fill cooling system (Refer to 7 - COOLING -
STANDARD PROCEDURE).
INSTALLATION - REAR AIR CONDITIONING
LINES
(1) Before installation, replace all O-rings and gas-
kets. Coat all sealing surfaces with approved wax-
free refrigerant oil.
(2) Install A/C line into rear block with nylon
wedge.
(3) Install A/C lines into five underbody brackets.
(4) Connect forward compression fittings.
(5) Install bolt at sealing block to rear A/C hous-
ing.
(6) Install ABS harness into clips.
(7) Install heater hoses into underbody brackets.
(8) Install lines into front hoses and install hose
clamps.
(9) Lower vehicle.
(10) Evacuate and recharge system.
(11) Fill cooling system (Refer to 7 - COOLING -
STANDARD PROCEDURE).
Fig. 14 UNDERBODY LINE WEDGES
1 - O-RING
2 - DISCHARGE LINE
3 - NYLON WEDGE
4 - SEALING BLOCK
5 - VISE
6 - SUCTION LINE
RSPLUMBING - REAR24 - 105
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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(5) Check exhaust pipe exhaust end placement and
make any final adjustments.
(6) Lower vehicle from lift.
FUEL DOSING PUMP
DESCRIPTION
The dosing pump is a combined delivery, dosing
and shut-off system for the fuel supply to the heater
from the vehicles fuel tank.
OPERATION
The dosing pump is an electrically operated pump
that receives its operation instructions from the sup-
plemental heater electronic control module. The
pump supplies diesel fuel from the fuel tank to the
heater unit.
REMOVAL
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. 2).
(2) Disconnect the fuel line between the dosing
pump and the heater unit.
NOTE: Position and retain heater fuel line to pre-
vent fuel leakage while servicing dosing pump.
NOTE: Utilize an approved fuel storage container to
catch any residual fuel.
(3) Disconnect the electrical connector to the fuel
pump by depressing the integral spring and pulling
the connector away from the pump.
(4) Remove the dosing pump from the rubber iso-
lation.
INSTALLATION
(1) Mount the rubber isolation back onto the
splash shield mounting flanges at two locations.
(2) Connect fuel lines to the dosing pump and the
heater unit. The connectors should point towards the
heater fuel line.
(3) Use aviation style clamps to attach the hose to
the fuel pump nipples(Refer to 24 - HEATING & AIR
Fig. 1 Diesel Cabin Heater Exhaust System
1 - Mounting screws (3)
2 - Steel heater exhaust pipe
3 - Exhaust clamp (2)4 - Flexible heater exhaust pipe
5 - Heater and heater shield
6 - Exhaust pipe mounting clips (3) (If Equipped)
24 - 108 DIESEL SUPPLEMENTAL HEATER - DCHA - EXPORTRS
EXHAUST TUBE (Continued)
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CONDITIONING/CABIN HEATER/FUEL LINE -
INSTALLATION).
(4) Connect the electrical connector to the fuel
pump by depressing the integral spring and pushing
the connector towards the dosing pump. Pull the con-
nector towards the heater to verify the installation.
(5) Verify function of the heater.
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 cabin heater line removed from 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 line shows any signs of being restricted
after air pressure is applied, then the fuel line should
be replaced.(5) Install the cabin heater line(Refer to 24 -
HEATING & AIR CONDITIONING/CABIN HEAT-
ER/FUEL LINE - INSTALLATION).
(6) Verify function of the heater.
REMOVAL
(1) Elevate vehicle on a lift taking note of the
heater exhaust tube flexible section.
(2) Remove clamps on dosing pump end of fuel line
and separate line from pump (Fig. 3).
NOTE: Have an approved fuel holding device ready
to capture any diesel fuel that drains from fuel line
or heater unit.
(3) Remove clamp from fuel line at fuel tank con-
nection and separate line from tank.
(4) Remove any retaining clips and remove line
from vehicle.
Fig. 2 Dosing Pump Fuel Line
1 - Fuel Line
2 - Retaining Clamps3 - Dosing Pump
4 - Heater Unit Air Intake Pipe
RSDIESEL SUPPLEMENTAL HEATER - DCHA - EXPORT24 - 109
FUEL DOSING PUMP (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)
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