hvac DODGE RAM 2003 Service Owner's Guide

(1) Insert the evaporator coil into the bottom of the
HVAC housing. Make sure that the evaporator drain
is clean and unrestricted and evaporator deflector
shield is also installed.
(2) Reassemble and reinstall the HVAC housing in
the vehicle. (Refer to 24 - HEATING & AIR CONDI-
TIONING/DISTRIBUTION/HVAC HOUSING -
ASSEMBLY) (Refer to 24 - HEATING & AIR CON-
DITIONING/DISTRIBUTION/HVAC HOUSING -
INSTALLATION)
NOTE: If the evaporator is replaced, add 60 millili-
ters (2 fluid ounces) of refrigerant oil to the refrig-
erant system.
A/C ORIFICE TUBE
DESCRIPTION
The fixed orifice tube is installed in the liquid line
between the outlet of the condenser and the inlet of
the evaporator. The fixed orifice tube is only serviced
as an integral part of the liquid line.
OPERATION
The inlet end of the fixed orifice tube has a nylon
mesh filter screen, which filters the refrigerant and
helps to reduce the potential for blockage of the
metering orifice by refrigerant system contaminants
(Fig. 14). The outlet end of the tube has a nylonmesh diffuser screen. The O-rings on the plastic body
of the fixed orifice tube seal the tube to the inside of
the liquid line and prevents the refrigerant from
bypassing the fixed metering orifice.
The fixed orifice tube is used to meter the flow of
liquid refrigerant into the evaporator coil. The high-
pressure liquid refrigerant from the condenser
expands into a low-pressure liquid as it passes
through the metering orifice and diffuser screen of
the fixed orifice tube.
The fixed orifice tube cannot be repaired and, if
faulty or plugged, the liquid line assembly must be
replaced.
DIAGNOSIS AND TESTING - FIXED ORIFICE
TUBE
The fixed orifice tube can be checked for proper
operation using the following procedure. However,
the fixed orifice tube is only serviced as a part of the
liquid line unit. If the results of this test indicate
that the fixed orifice tube is obstructed or missing,
the entire liquid line unit must be replaced.
WARNING: THE LIQUID LINE BETWEEN THE CON-
DENSER OUTLET AND THE FIXED ORIFICE TUBE
CAN BECOME HOT ENOUGH TO BURN THE SKIN.
USE EXTREME CAUTION WHEN PERFORMING THE
FOLLOWING TEST.
(1) Confirm that the refrigerant system is properly
charged. (Refer to 24 - HEATING & AIR CONDI-
TIONING - DIAGNOSIS AND TESTING - A/C PER-
FORMANCE)
(2) Start the engine. Turn on the air conditioning
system and confirm that the compressor clutch is
engaged.
(3) Allow the air conditioning system to operate for
five minutes.
(4) Lightly and cautiously touch the liquid line
near the condenser outlet at the front of the engine
Fig. 13 Dual Zone HVAC Housing- (typical single
zone)
1 - Passenger Side Blend Door Lever (if equipped)
2 - Passenger Side Blend Door (if equipped)
3 - Fin Sensor Wire
4 - Lower Blower Motor Mounting Housing
5 - HVAC Evaporator
6 - Fin Sensor
7 - Driver Side Blend Door
8 - Driver Side Blend Door Lever
Fig. 14 FIXED ORIFICE TUBE - TYPICAL
1 - DIFFUSER SCREEN
2 - ªOº RINGS
3 - INLET FILTER SCREEN
4 - ORIFICE
24 - 48 PLUMBINGDR
A/C EVAPORATOR (Continued)

INSTALLATION
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)(Refer to
24 - HEATING & AIR CONDITIONING/PLUMBING -
CAUTION - REFRIGERANT HOSES/LINES/TUBES
PRECAUTIONS)
(1) Install the accumulator to the bulkhead but do
not tighten yet.
(2) Remove the tape or plugs from the refrigerant
line fittings on the accumulator inlet and the evapo-
rator outlet. Connect the accumulator inlet refriger-
ant line coupler to the evaporator outlet. (Refer to 24
- HEATING & AIR CONDITIONING/PLUMBING -
STANDARD PROCEDURE - A/C LINE COUPLERS)
(3) Remove the tape or plugs from the refrigerant
line fittings on the suction line and the accumulator
outlet. Connect the suction line refrigerant line cou-
pler to the accumulator outlet. (Refer to 24 - HEAT-
ING & AIR CONDITIONING/PLUMBING -
STANDARD PROCEDURE - A/C LINE COUPLERS)
(4) Tighten the accumulator fasteners to 4.5 N´m
(40 in. lbs.).
(5) Connect the battery negative cable.
(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)
NOTE: If the accumulator is replaced, add 60 milli-
liters (2 fluid ounces) of refrigerant oil to the refrig-
erant system. Use only refrigerant oil of the type
recommended for the compressor in the vehicle.
HEATER CORE
DESCRIPTION
The heater core is located in the HVAC housing,
under the instrument panel. It is a heat exchanger
made of rows of tubes and fins.
The heater core is not repairable and if damaged it
must be replaced.
OPERATION
Engine coolant is circulated through heater hoses
to the heater core at all times. As the coolant flowsthrough the 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 blend door
allows control of the heater output air temperature
by controlling how much of the air flowing through
the HVAC housing is directed through the heater
core. The blower motor speed controls the volume of
air flowing through the HVAC housing.
The heater core cannot be repaired and, if faulty or
damaged, it must be replaced.
REMOVAL
NOTE: Disassembly of the HVAC housing is not
required to remove heater core.
(1) Remove the HVAC housing from the vehicle.
(Refer to 24 - HEATING & AIR CONDITIONING/
DISTRIBUTION/HVAC HOUSING - REMOVAL)
(2) Remove the screws and retainers that secure
the heater core to the HVAC housing.
(3) Lift the heater core out of the heater-A/C hous-
ing.
(4) Inspect all seals and repair or replace as
required.
INSTALLATION
(1) Place the heater core into the HVAC housing.
(2) Snap the retainers for the heater core to the
housing. Install and tighten the screws that secure
the heater core to the HVAC housing (if equipped).
Tighten the screws to 2.2 N´m (20 in. lbs.).
(3) Reinstall the HVAC housing in the vehicle.
(Refer to 24 - HEATING & AIR CONDITIONING/
DISTRIBUTION/HVAC HOUSING - INSTALLA-
TION)
REFRIGERANT
DESCRIPTION
The refrigerant used in this air conditioning sys-
tem is a HydroFluoroCarbon (HFC), type R-134a.
Unlike R-12, which is a ChloroFluoroCarbon (CFC),
R-134a refrigerant does not contain ozone-depleting
chlorine. R-134a refrigerant is a non-toxic, non-flam-
mable, clear, and colorless liquefied gas.
Even though R-134a does not contain chlorine, it
must be reclaimed and recycled just like CFC-type
refrigerants. This is because R-134a is a greenhouse
gas and can contribute to global warming.
OPERATION
R-134a refrigerant is not compatible with R-12
refrigerant in an air conditioning system. Even a
24 - 50 PLUMBINGDR
ACCUMULATOR (Continued)

HIGH-PRESSURE FUEL LINE LEAKS -
DIAGNOSIS AND TESTING.............14-69
HINGE - INSTALLATION.....23-16,23-22,23-31,
23-46
HINGE - INSTALLATION, CENTER SEAT
BACK..............................23-80
HINGE - REMOVAL....23-16,23-22,23-31,23-46
HINGE - REMOVAL, CENTER SEAT BACK . . 23-79
HINGE COVER - INSTALLATION, CENTER
SEAT BACK INERTIA..................23-78
HINGE COVER - REMOVAL, CENTER
SEAT BACK INERTIA..................23-78
HITCH - INSTALLATION, TRAILER........13-25
HITCH - REMOVAL, TRAILER...........13-25
HOAT COOLANT - DESCRIPTION..........7-37
HOISTING - STANDARD PROCEDURE......0-14
HOLDDOWN - DESCRIPTION, BATTERY . . . 8F-14
HOLDDOWN - INSTALLATION, BATTERY . . . 8F-14
HOLDDOWN - OPERATION, BATTERY.....8F-14
HOLDDOWN - REMOVAL, BATTERY......8F-14
HOLDER - INSTALLATION, CUP.........23-52
HOLDER - REMOVAL, CUP.............23-52
HOLDING CLUTCHES - DESCRIPTION....21-546
HOLDING CLUTCHES - OPERATION.....21-546
HOLE PLUG - INSTALLATION, CAMSHAFT
CORE..............................9-201
HOLE PLUG - REMOVAL, CAMSHAFT
CORE..............................9-200
HOLE REPAIR - DESCRIPTION,
THREADED........................Intro.-9
HONING - STANDARD PROCEDURE,
CYLINDER BORE.......9-126,9-233,9-360,9-37
HOOD - INSTALLATION................23-47
HOOD - REMOVAL....................23-47
HOOK - INSTALLATION, COAT...........23-67
HOOK - REMOVAL, COAT..............23-67
HOOK ASSEMBLY - INSTALLATION,
FRONT TOW........................13-26
HOOK ASSEMBLY - REMOVAL, FRONT
TOW ..............................13-26
HORN - DIAGNOSIS AND TESTING.......8H-1
HORN - INSTALLATION.................8H-2
HORN - REMOVAL....................8H-2
HORN SWITCH - DESCRIPTION..........8H-2
HORN SWITCH - DIAGNOSIS AND
TESTING............................8H-2
HORN SYSTEM - DESCRIPTION..........8H-1
HORN SYSTEM - DIAGNOSIS AND
TESTING............................8H-1
HORN SYSTEM - OPERATION............8H-1
HOSE - GEAR TO COOLER -
INSTALLATION, RETURN..........19-43,19-44
HOSE - GEAR TO COOLER - REMOVAL,
RETURN............................19-43
HOSE - INSTALLATION, FRONT BRAKE......5-9
HOSE - INSTALLATION, PRESSURE . 19-43,19-44
HOSE - INSTALLATION, REAR BRAKE.......5-9
HOSE - REMOVAL, FRONT...............5-9
HOSE - REMOVAL, PRESSURE.....19-43,19-44
HOSE - REMOVAL, REAR BRAKE..........5-8
HOSE - RESERVOIR TO COOLER -
INSTALLATION, RETURN..........19-43,19-44
HOSE - RESERVOIR TO COOLER -
REMOVAL, RETURN.............19-43,19-44
HOSE ASSEMBLY - INSTALLATION, REAR
TUBE................................5-9
HOSE ASSEMBLY - REMOVAL, REAR
TUBE................................5-8
HOSE CLAMPS - DESCRIPTION...........7-3
HOSE CLAMPS - OPERATION.............7-5
HOSE WITH AIR CONDITIONING -
INSTALLATION, WATER PUMP BYPASS....7-70
HOSE WITH AIR CONDITIONING -
REMOVAL, WATER PUMP BYPASS........7-68
HOSE WITHOUT AIR CONDITIONING -
INSTALLATION, WATER PUMP BYPASS....7-70
HOSE WITHOUT AIR CONDITIONING -
REMOVAL, WATER PUMP BYPASS........7-69
HOSES/LINES/TUBES PRECAUTIONS -
CAUTION, REFRIGERANT..............24-33
HOSES/TUBES - DESCRIPTION, WASHER . 8R-11
HOSES/TUBES - OPERATION, WASHER . . . 8R-11
HOUSING - ASSEMBLY, HVAC
...........24-28
HOUSING - DIAGNOSIS AND TESTING,
CLUTCH
..............................6-8
HOUSING - DISASSEMBLY, HVAC
........24-28
HOUSING - INSTALLATION, CLUTCH
......6-10
HOUSING - INSTALLATION, GEAR
........9-349HOUSING - INSTALLATION, HVAC........24-29
HOUSING - INSTALLATION, ROCKER.....9-304
HOUSING - REMOVAL, CLUTCH..........6-10
HOUSING - REMOVAL, GEAR...........9-348
HOUSING - REMOVAL, HVAC...........24-27
HOUSING - REMOVAL, ROCKER.........9-304
HOUSING BUSHING - INSTALLATION,
EXTENSION........................21-200
HOUSING BUSHING - REMOVAL,
EXTENSION........................21-200
HOUSING BUSHING AND SEAL -
INSTALLATION, EXTENSION.....21-616,21-682
HOUSING BUSHING AND SEAL -
REMOVAL, EXTENSION.........21-616,21-682
HOUSING COVER - INSTALLATION, GEAR . 9-350
HOUSING COVER - REMOVAL, GEAR.....9-349
HOUSING FLUID LEAK - DIAGNOSIS AND
TESTING, CONVERTER . . . 21-143,21-324,21-495
HOUSING SEAL - INSTALLATION,
ADAPTER...............21-127,21-539,21-83
HOUSING SEAL - INSTALLATION,
EXTENSION.......21-127,21-200,21-380,21-83
HOUSING SEAL - REMOVAL, ADAPTER . . 21-127,
21-539,21-83
HOUSING SEAL - REMOVAL,
EXTENSION.......21-127,21-200,21-380,21-83
HOUSING SEAL AND DUST BOOT -
INSTALLATION, EXTENSION.....21-652,21-716
HOUSING SEAL AND DUST BOOT -
REMOVAL, EXTENSION.........21-652,21-716
HOW TO USE WIRING DIAGRAMS -
DESCRIPTION.....................8W-01-1
H-SECTION REPLACEMENT - STANDARD
PROCEDURE, REAR FRAME............13-15
HUB / BEARING - INSTALLATION.........2-31
HUB / BEARING - REMOVAL.............2-30
HVAC HOUSING - ASSEMBLY...........24-28
HVAC HOUSING - DISASSEMBLY........24-28
HVAC HOUSING - INSTALLATION........24-29
HVAC HOUSING - REMOVAL............24-27
HYDRAULIC BOOSTER - DIAGNOSIS
AND TESTING........................5-25
HYDRAULIC LASH ADJUSTER -
DIAGNOSIS AND TESTING.........9-124,9-31
HYDRAULIC LIFTERS - CLEANING . . 9-260,9-388
HYDRAULIC LIFTERS - INSTALLATION . . . 9-260,
9-388
HYDRAULIC LIFTERS - REMOVAL . . . 9-259,9-387
HYDRAULIC PRESSURE TEST -
DIAGNOSIS AND TESTING......21-140,21-321,
21-493
HYDRAULIC SCHEMATICS, SCHEMATICS
AND DIAGRAMS........21-175,21-355,21-513
HYDRAULIC TAPPETS - DIAGNOSIS AND
TESTING......................9-258,9-386
HYDROBOOST - INSTALLATION..........5-22
HYDROBOOST - INSTALLATION, ALL
EXCEPT.............................5-22
HYDROBOOST - REMOVAL..............5-21
HYDROBOOST - REMOVAL, ALL EXCEPT . . . 5-21
HYDRO-BOOST BRAKE BOOSTER -
INSTALLATION........................5-27
HYDRO-BOOST BRAKE BOOSTER -
REMOVAL...........................5-27
HYDROFORM FENDER RAIL REPAIR -
STANDARD PROCEDURE...............13-12
HYDROSTATIC LOCK - STANDARD
PROCEDURE.........9-186,9-232,9-290,9-361
IDENTIFICATION - DESCRIPTION,
FASTENER.........................Intro.-6
IDENTIFICATION AND INFORMATION -
DESCRIPTION, SECTION.............8W-01-6
IDENTIFICATION NUMBER -
DESCRIPTION, VEHICLE..............Intro.-2
IDLE AIR CONTROL MOTOR -
DESCRIPTION.......................14-33
IDLE AIR CONTROL MOTOR -
INSTALLATION.......................14-35
IDLE AIR CONTROL MOTOR -
OPERATION.........................14-33
IDLE AIR CONTROL MOTOR - REMOVAL . . 14-34
IDLER SHAFT - INSTALLATION......9-175,9-80
IDLER SHAFT - REMOVAL
..........9-175,9-79
IGNITION - SPECIFICATIONS, TORQUE
.....8I-3
IGNITION CIRCUIT SENSE -
DESCRIPTION
.......................8E-10
IGNITION CIRCUIT SENSE - OPERATION
. . 8E-12
IGNITION COIL - DESCRIPTION
..........8I-19IGNITION COIL - INSTALLATION.........8I-24
IGNITION COIL - OPERATION............8I-20
IGNITION COIL - REMOVAL.............8I-23
IGNITION COIL CAPACITOR -
DESCRIPTION........................8I-33
IGNITION COIL CAPACITOR -
INSTALLATION.......................8I-33
IGNITION COIL CAPACITOR - OPERATION . . 8I-33
IGNITION COIL CAPACITOR - REMOVAL . . . 8I-33
IGNITION COIL RESISTANCE, 3.7L V-6.....8I-6
IGNITION COIL RESISTANCE, 4.7L V-8.....8I-6
IGNITION COIL RESISTANCE, 5.7L V-8.....8I-6
IGNITION COIL RESISTANCE, 5.9L.........8I-6
IGNITION COIL RESISTANCE, 8.0L V-10
ENGINE..............................8I-6
IGNITION CONTROL - DESCRIPTION.......8I-1
IGNITION SWITCH - DESCRIPTION........19-9
IGNITION SWITCH - DESCRIPTION,
KEY-IN.............................19-11
IGNITION SWITCH - DIAGNOSIS AND
TESTING............................19-9
IGNITION SWITCH - INSTALLATION......19-11
IGNITION SWITCH - OPERATION.........19-9
IGNITION SWITCH - REMOVAL..........19-10
IGNITION SWITCH AND KEY LOCK
CYLINDER - DIAGNOSIS AND TESTING . . . 19-11
IGNITION TIMING, SPECIFICATIONS.......8I-6
IGNITION-OFF DRAW TEST - STANDARD
PROCEDURE..........................8F-11
IMMOBILIZER MODULE - DESCRIPTION,
SENTRY KEY........................8E-13
IMMOBILIZER MODULE - INSTALLATION,
SENTRY KEY........................8E-15
IMMOBILIZER MODULE - OPERATION,
SENTRY KEY........................8E-13
IMMOBILIZER MODULE - REMOVAL,
SENTRY KEY........................8E-15
IMMOBILIZER SYSTEM INDICATOR
LAMP - DESCRIPTION, SENTRY KEY......8Q-5
IMMOBILIZER SYSTEM INDICATOR
LAMP - OPERATION, SENTRY KEY........8Q-5
IMMOBILIZER SYSTEM INITIALIZATION,
STANDARD PROCEDURE - SENTRY
KEY................................8Q-3
IMMOBILIZER SYSTEM (SKIS),
DESCRIPTION - SENTRY KEY............8Q-1
IMMOBILIZER SYSTEM TRANSPONDER
PROGRAMMING, STANDARD
PROCEDURE - SENTRY KEY.............8Q-4
IMPACT AIRBAG CONTROL MODULE -
DESCRIPTION, SIDE..................8O-53
IMPACT AIRBAG CONTROL MODULE -
OPERATION, SIDE....................8O-54
INCORRECT FLUID LEVEL - DIAGNOSIS
AND TESTING, EFFECTS OF.....21-201,21-381,
21-541
INDEPENDENT FRONT SUSPENSION -
DESCRIPTION, GEAR..................19-16
INDEPENDENT FRONT SUSPENSION -
INSTALLATION, GEAR.................19-17
INDEPENDENT FRONT SUSPENSION -
REMOVAL, GEAR.....................19-16
INDICATOR - DESCRIPTION, ABS........8J-17
INDICATOR - DESCRIPTION, AIRBAG.....8J-18
INDICATOR - DESCRIPTION, BRAKE/
PARK BRAKE........................8J-18
INDICATOR - DESCRIPTION, CARGO
LAMP..............................8J-20
INDICATOR - DESCRIPTION, CHECK
GAUGES............................8J-21
INDICATOR - DESCRIPTION, CRUISE.....8J-22
INDICATOR - DESCRIPTION, DOOR AJAR . . 8J-23
INDICATOR - DESCRIPTION, ETC........8J-24
INDICATOR - DESCRIPTION, GEAR
SELECTOR..........................8J-26
INDICATOR - DESCRIPTION, HIGH BEAM . . 8J-27
INDICATOR - DESCRIPTION, LAMP OUT . . . 8J-28
INDICATOR - DESCRIPTION, LOW FUEL . . . 8J-29
INDICATOR - DESCRIPTION, OVERDRIVE
OFF ...............................8J-33
INDICATOR - DESCRIPTION, SEATBELT
. . . 8J-34
INDICATOR - DESCRIPTION, SECURITY
. . . 8J-34
INDICATOR - DESCRIPTION, SERVICE
4WD
...............................8J-35
INDICATOR - DESCRIPTION, TRANS
TEMP
..............................8J-38
INDICATOR - DESCRIPTION, TURN
SIGNAL
............................8J-39
DRINDEX 17
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