2003 DODGE RAM warning

DISTRIBUTION
TABLE OF CONTENTS
page page
AIR OUTLETS
REMOVAL - PANEL OUTLETS.............24
INSTALLATION - PANEL OUTLETS..........24
BLEND DOOR
REMOVAL.............................24
INSTALLATION.........................25
BLOWER MOTOR
DESCRIPTION.........................25
OPERATION...........................25
DIAGNOSIS AND TESTING - BLOWER
MOTOR .............................26
REMOVAL.............................26
INSTALLATION.........................26
DEFROST DOOR
REMOVAL - DEFROST DOOR.............27
INSTALLATION - DEFROST DOOR..........27
FLOOR DISTRIBUTION DUCTS
REMOVAL.............................27INSTALLATION.........................27
HVAC HOUSING
REMOVAL.............................27
DISASSEMBLY.........................28
ASSEMBLY............................28
INSTALLATION.........................29
INSTRUMENT PANEL DUCTS
REMOVAL.............................29
INSTALLATION.........................29
MODE DOOR
REMOVAL - FLOOR - DEFROST DOOR......30
INSTALLATION - FLOOR - DEFROST DOOR . . 30
RECIRC DOOR
REMOVAL.............................30
INSTALLATION.........................30
AIR OUTLETS
REMOVAL - PANEL OUTLETS
(1) Use a trim stick or another suitable wide flat-
bladed tool to gently pry the panel outlet grill out of
the panel outlet housing (Fig. 1). The panel outlet
grill is retained by a light snap fit.
INSTALLATION - PANEL OUTLETS
To install, position the grill housing in the panel
outlet housing and press firmly until it snaps into
place.
BLEND DOOR
REMOVAL
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, DISABLE THE AIRBAG SYSTEM BEFORE
ATTEMPTING ANY STEERING WHEEL, STEERING
COLUMN, OR INSTRUMENT PANEL COMPONENT
DIAGNOSIS OR SERVICE. DISCONNECT AND ISO-
LATE THE BATTERY NEGATIVE (GROUND) CABLE,
THEN WAIT TWO MINUTES FOR THE AIRBAG SYS-
TEM CAPACITOR TO DISCHARGE BEFORE PER-
FORMING FURTHER DIAGNOSIS OR SERVICE. THIS
IS THE ONLY SURE WAY TO DISABLE THE AIRBAG
SYSTEM. FAILURE TO TAKE THE PROPER PRE-CAUTIONS COULD RESULT IN AN ACCIDENTAL
AIRBAG DEPLOYMENT AND POSSIBLE PERSONAL
INJURY.
Fig. 1 Dash Panel
1 - Headlight Switch
2 - Air Outlets
3 - Instrument Cluster
4 - Climate Control
5 - Radio
6 - Airbag
7 - Glove Box
8 - Heated Seat Switch (if equipped)
9 - Transfer Case Control Switch (if equipped)
10 - Cigar Lighter
11 - Cup Holders
12 - Ash Tray (if equipped)
13 - Power Outlet
24 - 24 DISTRIBUTIONDR

DIAGNOSIS AND TESTING - BLOWER MOTOR
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, DISABLE THE AIRBAG SYSTEM BEFORE
ATTEMPTING ANY STEERING WHEEL, STEERING
COLUMN, OR INSTRUMENT PANEL COMPONENT
DIAGNOSIS OR SERVICE. DISCONNECT AND ISO-
LATE THE BATTERY NEGATIVE (GROUND) CABLE,
THEN WAIT TWO MINUTES FOR THE AIRBAG SYS-
TEM CAPACITOR TO DISCHARGE BEFORE PER-
FORMING FURTHER DIAGNOSIS OR SERVICE. THIS
IS THE ONLY SURE WAY TO DISABLE THE AIRBAG
SYSTEM. FAILURE TO TAKE THE PROPER PRE-
CAUTIONS COULD RESULT IN AN ACCIDENTAL
AIRBAG DEPLOYMENT AND POSSIBLE PERSONAL
INJURY.
For circuit descriptions and diagrams, (Refer to
Appropriate Wiring Information). Possible causes of
an inoperative blower motor include:
²Faulty fuse
²Faulty blower motor circuit wiring or wire har-
ness connectors
²Faulty blower motor resistor
²Faulty blower motor relay
²Faulty blower motor switch
²Faulty A/C Heater mode control switch
²Faulty blower motor.
Possible causes of the blower motor not operating
in all speeds include:
²Faulty blower motor switch
²Faulty blower motor resistor
²Faulty blower motor circuit wiring or wire har-
ness connectors.
VIBRATION
Possible causes of blower motor vibration include:
²Improper blower motor mounting
²Improper blower wheel mounting
²Blower wheel out of balance or bent
²Blower motor faulty.
NOISE
To verify that the blower is the source of the noise,
unplug the blower motor wire harness connector and
operate the HVAC system. If the noise goes away,
possible causes include:
²Foreign material in the HVAC housing
²Improper blower motor mounting
²Improper blower wheel mounting
²Blower motor faulty.
REMOVAL
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, DISABLE THE AIRBAG SYSTEM BEFORE
ATTEMPTING ANY STEERING WHEEL, STEERINGCOLUMN, OR INSTRUMENT PANEL COMPONENT
DIAGNOSIS OR SERVICE. DISCONNECT AND ISO-
LATE THE BATTERY NEGATIVE (GROUND) CABLE,
THEN WAIT TWO MINUTES FOR THE AIRBAG SYS-
TEM CAPACITOR TO DISCHARGE BEFORE PER-
FORMING FURTHER DIAGNOSIS OR SERVICE. THIS
IS THE ONLY SURE WAY TO DISABLE THE AIRBAG
SYSTEM. FAILURE TO TAKE THE PROPER PRE-
CAUTIONS COULD RESULT IN AN ACCIDENTAL
AIRBAG DEPLOYMENT AND POSSIBLE PERSONAL
INJURY.
The blower motor is located on the passenger side
of the vehicle under the dash
(1) Disconnect and isolate the battery negative
cable.
(2) Unplug the blower motor wire harness connec-
tor (Fig. 3).
(3) Remove the three screws that secure the
blower motor and wheel assembly to the HVAC hous-
ing.
(4) Rotate and tilt the blower motor unit as needed
for clearance to remove the blower motor and wheel
from the HVAC housing.
INSTALLATION
(1) Align and install the blower motor and wheel
assembly into the HVAC housing.
(2) Install the three mounting screws and tighten
to 2.2 N´m (20 in. lbs.).
Fig. 3 Blower Motor Assembly- (Case Removed
from vehicle for graphic)
1 - Blower Motor Resistor Mounting Screws (2)
2 - Blower Motor Resistor
3 - Blower Motor Resistor Connector
4 - Blower Motor Mounting Screw
5 - Blower Motor Assmebly
6 - Blower Motor Wire
7 - Blower Motor Mounting Screw
8 - HVAC Housing
9 - Blower Motor Wire Hold Down
10 - Blower Motor Mounting Screw
24 - 26 DISTRIBUTIONDR
BLOWER MOTOR (Continued)

(3) Plug in the blower motor wire harness connec-
tor.
(4) Connect the battery negative cable.
DEFROST DOOR
REMOVAL - DEFROST DOOR
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, DISABLE THE AIRBAG SYSTEM BEFORE
ATTEMPTING ANY STEERING WHEEL, STEERING
COLUMN, OR INSTRUMENT PANEL COMPONENT
DIAGNOSIS OR SERVICE. DISCONNECT AND ISO-
LATE THE BATTERY NEGATIVE (GROUND) CABLE,
THEN WAIT TWO MINUTES FOR THE AIRBAG SYS-
TEM CAPACITOR TO DISCHARGE BEFORE PER-
FORMING FURTHER DIAGNOSIS OR SERVICE. THIS
IS THE ONLY SURE WAY TO DISABLE THE AIRBAG
SYSTEM. FAILURE TO TAKE THE PROPER PRE-
CAUTIONS COULD RESULT IN AN ACCIDENTAL
AIRBAG DEPLOYMENT AND POSSIBLE PERSONAL
INJURY.
WARNING: (Refer to 24 - HEATING & AIR CONDI-
TIONING/PLUMBING - WARNING) and (Refer to 24 -
HEATING & AIR CONDITIONING/PLUMBING - CAU-
TION).
(1) Recover refrigerant(Refer to 24 - HEATING &
AIR CONDITIONING/PLUMBING - STANDARD
PROCEDURE).
(2) Remove and disassemble the HVAC housing.
(Refer to 24 - HEATING & AIR CONDITIONING/
DISTRIBUTION/HVAC HOUSING - REMOVAL)
(Refer to 24 - HEATING & AIR CONDITIONING/
DISTRIBUTION/HVAC HOUSING - DISASSEMBLY)
(3) Remove the defrost door actuator.
(4) Remove the defrost door from the HVAC hous-
ing, by first removing the actuator if not already
removed. Then carefully move the door so that one
pivot point cleans then tilt and lift the door out of
the HVAC housing.
INSTALLATION - DEFROST DOOR
(1) Install the defrost door in the HVAC housing.
(2) Install the defrost door actuator.
(3) Assemble the HVAC housing. (Refer to 24 -
HEATING & AIR CONDITIONING/DISTRIBUTION/
HVAC HOUSING - ASSEMBLY)
(4) Install the HVAC housing in the vehicle. (Refer
to 24 - HEATING & AIR CONDITIONING/DISTRI-
BUTION/HVAC HOUSING - INSTALLATION)
(5) Run calibration test.
FLOOR DISTRIBUTION DUCTS
REMOVAL
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, DISABLE THE AIRBAG SYSTEM BEFORE
ATTEMPTING ANY STEERING WHEEL, STEERING
COLUMN, OR INSTRUMENT PANEL COMPONENT
DIAGNOSIS OR SERVICE. DISCONNECT AND ISO-
LATE THE BATTERY NEGATIVE (GROUND) CABLE,
THEN WAIT TWO MINUTES FOR THE AIRBAG SYS-
TEM CAPACITOR TO DISCHARGE BEFORE PER-
FORMING FURTHER DIAGNOSIS OR SERVICE. THIS
IS THE ONLY SURE WAY TO DISABLE THE AIRBAG
SYSTEM. FAILURE TO TAKE THE PROPER PRE-
CAUTIONS COULD RESULT IN AN ACCIDENTAL
AIRBAG DEPLOYMENT AND POSSIBLE PERSONAL
INJURY.
(1) Remove the screws that secure the floor duct to
the HVAC housing.
(2) Remove the floor duct from the HVAC housing.
INSTALLATION
(1) Install the floor duct on the HVAC housing.
(2) Install the screws that secure the floor duct to
the HVAC housing. Tighten the mounting screws to
2.2 N´m (20 in. lbs.).
(3) Install the battery negative cable.
HVAC HOUSING
REMOVAL
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, DISABLE THE AIRBAG SYSTEM BEFORE
ATTEMPTING ANY STEERING WHEEL, STEERING
COLUMN, OR INSTRUMENT PANEL COMPONENT
DIAGNOSIS OR SERVICE. DISCONNECT AND ISO-
LATE THE BATTERY NEGATIVE (GROUND) CABLE,
THEN WAIT TWO MINUTES FOR THE AIRBAG SYS-
TEM CAPACITOR TO DISCHARGE BEFORE PER-
FORMING FURTHER DIAGNOSIS OR SERVICE. THIS
IS THE ONLY SURE WAY TO DISABLE THE AIRBAG
SYSTEM. FAILURE TO TAKE THE PROPER PRE-
CAUTIONS COULD RESULT IN AN ACCIDENTAL
AIRBAG DEPLOYMENT AND POSSIBLE PERSONAL
INJURY.
(1) Disconnect and isolate the battery negative
cable.
(2) Remove the instrument panel from the vehi-
cle(Refer to 23 - BODY/INSTRUMENT PANEL -
REMOVAL).
DRDISTRIBUTION 24 - 27
BLOWER MOTOR (Continued)

(2) Install the screws and snap clips that secure
the upper and lower HVAC housing halves to each
other. Tighten the screws to 2.2 N´m (20 in. lbs.).
(3) Install the blower motor and wheel unit in the
HVAC housing. (Refer to 24 - HEATING & AIR CON-
DITIONING/DISTRIBUTION/BLOWER MOTOR -
INSTALLATION)
(4) Install the foam seals on the flanges around
the heater core and evaporator coil tube mounting
flange of the HVAC housing. Repair or replace any
seals as required.
(5) Install the electrical wiring harness for the
acutators. Make sure the wires are routed through
all wiring retainers, replace any retainers that are
damaged or missing.
(6) Connect the wiring harness to each actuator,
making sure each connector is securely attached.
INSTALLATION
WARNING: IF THE VEHICLE IS EQUIPPED WITH AIR
CONDITIONING, REVIEW THE WARNINGS AND
CAUTIONS IN PLUMBING BEFORE PERFORMING
THE FOLLOWING OPERATION. (Refer to 24 - HEAT-
ING & AIR CONDITIONING/PLUMBING - WARNING)
(Refer to 24 - HEATING & AIR CONDITIONING/
PLUMBING - CAUTION) (Refer to 24 - HEATING &
AIR CONDITIONING/PLUMBING - CAUTION -
REFRIGERANT HOSES/LINES/TUBES PRECAU-
TIONS)
(1) Position the HVAC housing to the dash panel.
Be certain that the evaporator condensate drain tube
and the housing mounting studs are inserted into
their correct mounting holes.
(2) Install and tighten the nuts onto the HVAC
housing mounting studs. Tighten the nuts to 6.2 N´m
(55 in.lbs.).
(3) Connect the HVAC system electrical connec-
tors.
(4) Unplug or remove the tape from the heater
core tubes. Connect the heater hoses to the heater
core tubes and fill the engine cooling system(Refer to
7 - COOLING/ENGINE - STANDARD PROCE-
DURE).
(5) Unplug or remove the tape from the liquid line
and the evaporator inlet tube fittings. Connect the
liquid line coupler to the evaporator inlet tube. (Refer
to 24 - HEATING & AIR CONDITIONING/PLUMB-
ING - STANDARD PROCEDURE - A/C LINE COU-
PLERS)(6) Evacuate the refrigerant system. (Refer to 24 -
HEATING & AIR CONDITIONING/PLUMBING -
STANDARD PROCEDURE - REFRIGERANT SYS-
TEM EVACUATE)
(7) Charge the refrigerant system. (Refer to 24 -
HEATING & AIR CONDITIONING/PLUMBING -
STANDARD PROCEDURE - REFRIGERANT SYS-
TEM CHARGE)
(8) Install the instrument panel in the vehicle(Re-
fer to 23 - BODY/INSTRUMENT PANEL - INSTAL-
LATION).
(9) Connect the battery negative cable.
(10) Start the engine and check for proper opera-
tion of the heating and air conditioning systems.
(11) Run the calibration procedure.
INSTRUMENT PANEL DUCTS
REMOVAL
(1) Disconnect and isolate the battery negative
cable.
(2) Remove the HVAC assembly from the vehi-
cle(Refer to 24 - HEATING & AIR CONDITIONING/
DISTRIBUTION/HVAC HOUSING - REMOVAL).
(3) Disasemble the HVAC housing(Refer to 24 -
HEATING & AIR CONDITIONING/DISTRIBUTION/
HVAC HOUSING - DISASSEMBLY).
(4) Remove the panel door actuator from the hous-
ing if not already removed.
(5) With the actuator removed you can take the
door and shift it so that one pivot point will clear the
housing. You can then tilt the door and remove it
from the housing.
INSTALLATION
(1) Take the door and tilt it so one pivot point is
installed. The carfully install the second pivot point.
Check to be sure no binding of the door is occuring,
repair as required.
(2) Reassemble the HVAC housing(Refer to 24 -
HEATING & AIR CONDITIONING/DISTRIBUTION/
HVAC HOUSING - ASSEMBLY).
(3) Install the HVAC assembly into the vehicle(Re-
fer to 24 - HEATING & AIR CONDITIONING/DIS-
TRIBUTION/INSTRUMENT PANEL DUCTS -
INSTALLATION).
(4) Connect the battery negative cable.
DRDISTRIBUTION 24 - 29
HVAC HOUSING (Continued)

MODE DOOR
REMOVAL - FLOOR - DEFROST DOOR
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, DISABLE THE AIRBAG SYSTEM BEFORE
ATTEMPTING ANY STEERING WHEEL, STEERING
COLUMN, OR INSTRUMENT PANEL COMPONENT
DIAGNOSIS OR SERVICE. DISCONNECT AND ISO-
LATE THE BATTERY NEGATIVE (GROUND) CABLE,
THEN WAIT TWO MINUTES FOR THE AIRBAG SYS-
TEM CAPACITOR TO DISCHARGE BEFORE PER-
FORMING FURTHER DIAGNOSIS OR SERVICE. THIS
IS THE ONLY SURE WAY TO DISABLE THE AIRBAG
SYSTEM. FAILURE TO TAKE THE PROPER PRE-
CAUTIONS COULD RESULT IN AN ACCIDENTAL
AIRBAG DEPLOYMENT AND POSSIBLE PERSONAL
INJURY.
WARNING: (Refer to 24 - HEATING & AIR CONDI-
TIONING/PLUMBING - WARNING) and (Refer to 24 -
HEATING & AIR CONDITIONING/PLUMBING - CAU-
TION).
(1) Remove and disassemble the HVAC housing.
(Refer to 24 - HEATING & AIR CONDITIONING/
DISTRIBUTION/HVAC HOUSING - REMOVAL)
(Refer to 24 - HEATING & AIR CONDITIONING/
DISTRIBUTION/HVAC HOUSING - DISASSEMBLY)
(2) Remove the floor door actuator from the lower
HVAC housing. (Refer to 24 - HEATING & AIR CON-
DITIONING/CONTROLS/MODE DOOR ACTUATOR
- REMOVAL - FLOOR DOOR ACTUATOR)
(3) Take the defrost door and shift it so that one
pivot point clears the door and remove from the
HVAC housing.
INSTALLATION - FLOOR - DEFROST DOOR
(1) Install the floor-defrost door in the HVAC hous-
ing by placing the door in the lower housing.
(2) Assemble the HVAC housing. (Refer to 24 -
HEATING & AIR CONDITIONING/DISTRIBUTION/
HVAC HOUSING - ASSEMBLY)
(3) Install the floor door actuator to the lower
HVAC housing. (Refer to 24 - HEATING & AIR CON-
DITIONING/CONTROLS/MODE DOOR ACTUATOR
- INSTALLATION - FLOOR DOOR ACTUATOR)
(4) Install the HVAC housing in the vehicle. (Refer
to 24 - HEATING & AIR CONDITIONING/DISTRI-
BUTION/HVAC HOUSING - INSTALLATION)
RECIRC DOOR
REMOVAL
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, DISABLE THE AIRBAG SYSTEM BEFORE
ATTEMPTING ANY STEERING WHEEL, STEERING
COLUMN, OR INSTRUMENT PANEL COMPONENT
DIAGNOSIS OR SERVICE. DISCONNECT AND ISO-
LATE THE BATTERY NEGATIVE (GROUND) CABLE,
THEN WAIT TWO MINUTES FOR THE AIRBAG SYS-
TEM CAPACITOR TO DISCHARGE BEFORE PER-
FORMING FURTHER DIAGNOSIS OR SERVICE. THIS
IS THE ONLY SURE WAY TO DISABLE THE AIRBAG
SYSTEM. FAILURE TO TAKE THE PROPER PRE-
CAUTIONS COULD RESULT IN AN ACCIDENTAL
AIRBAG DEPLOYMENT AND POSSIBLE PERSONAL
INJURY.
WARNING: IF THE VEHICLE IS EQUIPPED WITH AIR
CONDITIONING, REVIEW THE WARNINGS AND
CAUTIONS IN PLUMBING BEFORE PERFORMING
THE FOLLOWING OPERATION. (Refer to 24 - HEAT-
ING & AIR CONDITIONING/PLUMBING - WARNING)
(Refer to 24 - HEATING & AIR CONDITIONING/
PLUMBING - CAUTION)
(1) Remove the HVAC housing and disassemble.
(Refer to 24 - HEATING & AIR CONDITIONING/
DISTRIBUTION/HVAC HOUSING - REMOVAL)
(Refer to 24 - HEATING & AIR CONDITIONING/
DISTRIBUTION/HVAC HOUSING - DISASSEMBLY)
(2) Remove the four screws to remove the recircu-
lation door assembly. (Refer to 24 - HEATING & AIR
CONDITIONING/CONTROLS/RECIRCULATION
DOOR ACTUATOR - REMOVAL)
(3) With the actuator remove take the recircula-
tion door and move it to one side so that one pivot
point clears the housing. The tilt the recirculation
door and remove from the assembly.
INSTALLATION
(1) Guide the recirculation door lever through the
air intake grille of the HVAC housing while installing
the door in the housing.
(2) Assemble the HVAC housing. (Refer to 24 -
HEATING & AIR CONDITIONING/DISTRIBUTION/
HVAC HOUSING - ASSEMBLY)
(3) Install the HVAC housing in the vehicle. (Refer
to 24 - HEATING & AIR CONDITIONING/DISTRI-
BUTION/HVAC HOUSING - INSTALLATION)
(4) Install the recirculation door actuator on the
HVAC housing. (Refer to 24 - HEATING & AIR CON-
DITIONING/CONTROLS/RECIRCULATION DOOR
ACTUATOR - INSTALLATION)
24 - 30 DISTRIBUTIONDR

PLUMBING
TABLE OF CONTENTS
page page
PLUMBING
DESCRIPTION - REFRIGERANT LINE.......32
OPERATION- REFRIGERANT LINES........32
WARNING
SERVICE WARNINGS..................32
CAUTION
SERVICE CAUTIONS..................33
CAUTION - REFRIGERANT HOSES/LINES/
TUBES PRECAUTIONS.................33
STANDARD PROCEDURE
STANDARD PROCEDURE - REFRIGERANT
SYSTEM SERVICE EQUIPMENT..........34
STANDARD PROCEDURE - REFRIGERANT
RECOVERY..........................34
STANDARD PROCEDURE - REFRIGERANT
SYSTEM EVACUATE...................35
STANDARD PROCEDURE - REFRIGERANT
SYSTEM CHARGE.....................35
SPECIFICATIONS - CHARGE CAPACITY.....35
A/C COMPRESSOR
DESCRIPTION
DESCRIPTION........................35
DESCRIPTION - HIGH PRESSURE RELIEF
VALVE..............................35
OPERATION
OPERATION.........................36
OPERATION - HIGH PRESSURE RELIEF
VALVE..............................36
DIAGNOSIS AND TESTING - A/C
COMPRESSOR NOISE.................36
REMOVAL
REMOVAL...........................37
REMOVAL - 5.9L DIESEL ENGINE.........37
INSTALLATION
INSTALLATION.......................38
INSTALLATION - 5.9L DIESEL ENGINE.....39
A/C CONDENSER
DESCRIPTION.........................39
OPERATION...........................39
REMOVAL
REMOVAL - 3.7, 4.7 and 5.7L ENGINES....39
REMOVAL - 5.9L DIESEL ENGINE.........40
REMOVAL - 8.0L Engine................40
INSTALLATION
INSTALLATION - 3.7, 4.7 and 5.7L ENGINES . 41
INSTALLATION - 5.9L DIESEL ENGINE.....42
INSTALLATION - 8.0L Engine.............42A/C CONDENSER FAN
REMOVAL - CONDENSER FAN (GAS ENGINE
ONLY - 3.7, 4.7 & 5.7L).................43
INSTALLATION - CONDENSER FAN (GAS
ENGINE ONLY - 3.7, 4.7 & 5.7L)..........43
A/C DISCHARGE LINE
REMOVAL
REMOVAL...........................43
REMOVAL - 5.9L DIESEL ENGINE.........43
INSTALLATION
INSTALLATION.......................44
INSTALLATION - 5.9L DIESEL ENGINE.....44
LIQUID LINE
REMOVAL.............................45
INSTALLATION.........................45
SUCTION LINE
REMOVAL
REMOVAL...........................46
REMOVAL - 5.9L DIESEL ENGINE.........46
INSTALLATION
INSTALLATION.......................46
INSTALLATION.......................47
A/C EVAPORATOR
DESCRIPTION.........................47
OPERATION...........................47
REMOVAL.............................47
INSTALLATION.........................47
A/C ORIFICE TUBE
DESCRIPTION.........................48
OPERATION...........................48
DIAGNOSIS AND TESTING - FIXED ORIFICE
TUBE...............................48
REMOVAL.............................49
INSTALLATION.........................49
ACCUMULATOR
DESCRIPTION.........................49
OPERATION...........................49
REMOVAL.............................49
INSTALLATION.........................50
HEATER CORE
DESCRIPTION.........................50
OPERATION...........................50
REMOVAL.............................50
INSTALLATION.........................50
REFRIGERANT
DESCRIPTION.........................50
OPERATION...........................50
DIAGNOSIS AND TESTING- REFRIGERANT
SYSTEM LEAKS......................51
DRPLUMBING 24 - 31

STANDARD PROCEDURE
STANDARD PROCEDURE - REFRIGERANT
SYSTEM EVACUATE...................51
STANDARD PROCEDURE- REFRIGERANT
RECOVERY..........................52
STANDARD PROCEDURE- REFRIGERANT
SYSTEM CHARGE.....................52
REFRIGERANT LINE COUPLER
DESCRIPTION.........................52OPERATION...........................52
REMOVAL.............................52
INSTALLATION.........................53
REFRIGERANT OIL
DESCRIPTION.........................54
OPERATION...........................54
STANDARD PROCEDURE - REFRIGERANT
OIL LEVEL...........................54
PLUMBING
DESCRIPTION - REFRIGERANT LINE
The refrigerant lines and hoses are used to carry
the refrigerant between the various air conditioning
system components. A barrier hose design with a
nylon tube, which is sandwiched between rubber lay-
ers, is used for the R-134a air conditioning system on
this vehicle. This nylon tube helps to further contain
the R-134a refrigerant, which has a smaller molecu-
lar structure than R-12 refrigerant. The ends of the
refrigerant hoses are made from lightweight alumi-
num or steel, and commonly use braze-less fittings.
Any kinks or sharp bends in the refrigerant plumb-
ing will reduce the capacity of the entire air condi-
tioning system. Kinks and sharp bends reduce the
flow of refrigerant in the system. A good rule for the
flexible hose refrigerant lines is to keep the radius of
all bends at least ten times the diameter of the hose.
In addition, the flexible hose refrigerant lines should
be routed so they are at least 80 millimeters (3
inches) from an exhaust manifold.
OPERATION- REFRIGERANT LINES
High pressures are produced in the refrigerant sys-
tem when the air conditioning compressor is operat-
ing. Extreme care must be exercised to make sure
that each of the refrigerant system connections is
pressure-tight and leak free. It is a good practice to
inspect all flexible hose refrigerant lines at least once
a year to make sure they are in good condition and
properly routed.
The refrigerant lines and hoses are coupled with
other components of the HVAC system with either 3
O-ring spring lock couplings or dual axes seals.
The refrigerant lines and hoses cannot be repaired
and, if faulty or damaged, they must be replaced.
WARNING
SERVICE WARNINGS
WARNING: THE AIR CONDITIONING SYSTEM CON-
TAINS REFRIGERANT UNDER HIGH PRESSURE.
SEVERE PERSONAL INJURY MAY RESULT FROM
IMPROPER SERVICE PROCEDURES. REPAIRS
SHOULD ONLY BE PERFORMED BY QUALIFIED
SERVICE PERSONNEL.
AVOID BREATHING THE REFRIGERANT AND
REFRIGERANT OIL VAPOR OR MIST. EXPOSURE
MAY IRRITATE THE EYES, NOSE, AND/OR THROAT.
WEAR EYE PROTECTION WHEN SERVICING THE
AIR CONDITIONING REFRIGERANT SYSTEM. SERI-
OUS EYE INJURY CAN RESULT FROM DIRECT
CONTACT WITH THE REFRIGERANT. IF EYE CON-
TACT OCCURS, SEEK MEDICAL ATTENTION IMME-
DIATELY.
DO NOT EXPOSE THE REFRIGERANT TO OPEN
FLAME. POISONOUS GAS IS CREATED WHEN
REFRIGERANT IS BURNED. AN ELECTRONIC LEAK
DETECTOR IS RECOMMENDED.
IF ACCIDENTAL SYSTEM DISCHARGE OCCURS,
VENTILATE THE WORK AREA BEFORE RESUMING
SERVICE. LARGE AMOUNTS OF REFRIGERANT
RELEASED IN A CLOSED WORK AREA WILL DIS-
PLACE THE OXYGEN AND CAUSE SUFFOCATION.
THE EVAPORATION RATE OF R-134a REFRIGER-
ANT AT AVERAGE TEMPERATURE AND ALTITUDE
IS EXTREMELY HIGH. AS A RESULT, ANYTHING
THAT COMES IN CONTACT WITH THE REFRIGER-
ANT WILL FREEZE. ALWAYS PROTECT THE SKIN
OR DELICATE OBJECTS FROM DIRECT CONTACT
WITH THE REFRIGERANT.
THE R-134a SERVICE EQUIPMENT OR THE VEHI-
CLE REFRIGERANT SYSTEM SHOULD NOT BE
PRESSURE TESTED OR LEAK TESTED WITH COM-
PRESSED AIR. SOME MIXTURES OF AIR AND
R-134a HAVE BEEN SHOWN TO BE COMBUSTIBLE
AT ELEVATED PRESSURES. THESE MIXTURES ARE
POTENTIALLY DANGEROUS, AND MAY RESULT IN
FIRE OR EXPLOSION CAUSING INJURY OR PROP-
ERTY DAMAGE.
24 - 32 PLUMBINGDR

The refrigerant system will remain chemically sta-
ble as long as pure, moisture-free R-134a refrigerant
and refrigerant oil is used. Dirt, moisture, or air can
upset this chemical stability. Operational troubles or
serious damage can occur if foreign material is
present in the refrigerant system.
When it is necessary to open the refrigerant sys-
tem, have everything needed to service the system
ready. The refrigerant system should not be left open
to the atmosphere any longer than necessary. Cap or
plug all lines and fittings as soon as they are opened
to prevent the entrance of dirt and moisture. All lines
and components in parts stock should be capped or
sealed until they are to be installed.
All tools, including the refrigerant recycling equip-
ment, the manifold gauge set, and test hoses should
be kept clean and dry. All tools and equipment must
be designed for R-134a refrigerant.
STANDARD PROCEDURE
STANDARD PROCEDURE - REFRIGERANT
SYSTEM SERVICE EQUIPMENT
WARNING: REVIEW THE WARNINGS AND CAU-
TIONS IN THE FRONT OF THIS SECTION BEFORE
PERFORMING THE FOLLOWING OPERATION.
(Refer to 24 - HEATING & AIR CONDITIONING/
PLUMBING - WARNING) (Refer to 24 - HEATING &
AIR CONDITIONING/PLUMBING - CAUTION)
When servicing the air conditioning system, a
R-134a refrigerant recovery/recycling/charging sta-
tion that meets SAE Standard J2210 must be used.
Contact an automotive service equipment supplier for
refrigerant recovery/recycling/charging equipment.
Refer to the operating instructions supplied by the
equipment manufacturer for proper care and use of
this equipment.
A manifold gauge set may be needed with some
recovery/recycling/charging equipment (Fig. 1). The
service hoses on the gauge set being used should
have manual (turn wheel), or automatic back-flow
valves at the service port connector ends. This will
prevent refrigerant from being released into the
atmosphere.
MANIFOLD GAUGE SET CONNECTIONS
CAUTION: Do not use an R-12 manifold gauge set
on an R-134a system. The refrigerants are not com-
patible and system damage will result.
LOW PRESSURE GAUGE HOSE The low pressure
hose (Blue with Black stripe) attaches to the suctionservice port. This port is located on the suction line
between the accumulator outlet and the compressor.
HIGH PRESSURE GAUGE HOSE The high pres-
sure hose (Red with Black stripe) attaches to the dis-
charge service port. This port is located on the liquid
line between the condenser outlet and the evaporator.
RECOVERY/RECYCLING/EVACUATION/CHARG-
ING HOSE The center manifold hose (Yellow, or
White, with Black stripe) is used to recover, evacu-
ate, and charge the refrigerant system. When the low
or high pressure valves on the manifold gauge set
are opened, the refrigerant in the system will escape
through this hose.
STANDARD PROCEDURE - REFRIGERANT
RECOVERY
WARNING: REVIEW THE WARNINGS AND CAU-
TIONS IN THE FRONT OF THIS SECTION BEFORE
PERFORMING THE FOLLOWING OPERATION.
(Refer to 24 - HEATING & AIR CONDITIONING/
PLUMBING - WARNING) (Refer to 24 - HEATING &
AIR CONDITIONING/PLUMBING - CAUTION)
A R-134a refrigerant recovery/recycling/charging
station that meets SAE Standard J2210 must be
used to recover the refrigerant from an R-134a refrig-
Fig. 1 MANIFOLD GAUGE SET - TYPICAL
1 - HIGH PRESSURE GAUGE
2 - VALVE
3 - VACUUM/REFRIGERANT HOSE (YELLOW W/ BLACK STRIPE)
4 - HIGH PRESSURE HOSE (RED W/ BLACK STRIPE)
5 - LOW PRESSURE HOSE (BLUE W/ BLACK STRIPE)
6 - VALVE
7 - LOW PRESSURE GAUGE
24 - 34 PLUMBINGDR
PLUMBING (Continued)