HVAC Control connector DODGE RAM 2002 Service User Guide

(3) Reach through the glove box opening to access
and unplug the vacuum harness connector from the
recirculation door actuator (Fig. 27).
(4) Loosen the two nuts that secure the recircula-
tion door actuator to the mounting bracket on the
HVAC housing.
(5) Slide the two actuator mounting studs out of
the slots in the actuator mounting bracket.
(6) Pull the recirculation door actuator downward
far enough to access the clip that retains the actua-
tor link to the recirculation door lever.
(7) Unsnap the clip from the recirculation door
actuator link and disengage the link from the recir-
culation door lever.
(8) Remove the recirculation door actuator from
the HVAC housing.
INSTALLATION
NOTE: When reinstalling the recirculation door
actuator, insert a screwdriver or another suitable
tool through the recirculation air intake grille to
prop the recirculation air door up in the open posi-
tion far enough to access the recirculation air door
lever through the instrument panel glove box open-
ing.NOTE: Before installing the blend door actuator, be
certain that the blend door is not binding.
(1) Snap the clip on the recirculation door actuator
link to engage the link to the recirculation door lever.
(2) Slide the two actuator mounting studs into the
slots in the actuator mounting bracket.
(3) Install the two nuts that secure the recircula-
tion door actuator to the mounting bracket on the
HVAC housing. Tighten the mounting nuts until the
recirculation air door actuator is seated to the
mounting bracket.
(4) Plug in the vacuum harness connector to the
recirculation door actuator.
(5) Install the glove box in the instrument panel-
(Refer to 23 - BODY/INSTRUMENT PANEL/GLOVE
BOX - INSTALLATION).
(6) Connect the battery negative cable.
VACUUM CHECK VALVE
DESCRIPTION
On models with a gasoline engine, a vacuum check
valve is installed in the accessory vacuum supply line
near the vacuum tap on the right side of the engine
intake manifold. On models with a diesel engine, a
vacuum check valve is installed on the engine vac-
uum pump. The vacuum check valve is designed to
allow vacuum to flow in only one direction through
the accessory vacuum supply circuits.
OPERATION
The use of a vacuum check valve helps to maintain
the system vacuum needed to retain the selected
HVAC mode and vehicle speed control settings. On
gasoline engine models, it prevents the engine from
bleeding down system vacuum through the intake
manifold during extended heavy engine load (low
engine vacuum) operation. On diesel engine models,
it prevents oil from contaminating the vacuum sup-
ply system by maintaining vacuum in the pump after
the engine is shut-off.
On gasoline engine models, a second vacuum check
valve is installed in the accessory vacuum supply line
at the tee fitting near the dash panel in the engine
compartment. This check valve also helps to main-
tain the system vacuum needed to retain the selected
HVAC mode settings, but isolates the HVAC vacuum
circuit from the vehicle speed control vacuum circuit.
It prevents the vehicle speed control servo from
bleeding down the HVAC system vacuum during
extended heavy engine load operation.
The vacuum check valve cannot be repaired and, if
faulty or damaged, it must be replaced.
Fig. 27 RECIRCULATION DOOR ACTUATOR
1 - DOOR SHAFT RETAINER
2 - RECIRCULATING AIR DOOR
3 - ROD CLIP
4 - BLOWER MOTOR ELECTRICAL CONNECTOR
5 - ACTUATOR
6 - BLOWER MOTOR
7 - VACUUM LINE
24 - 28 CONTROLSBR/BE
RECIRCULATION DOOR ACTUATOR (Continued)

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 fuse
²Faulty blower motor switch
²Faulty blower motor resistor
²Faulty blower motor relay
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 deformed
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
(1) Disconnect and isolate the battery negative
cable.
(2) Disconnect the blower motor cooling tube from
the nipple on the blower motor housing (Fig. 3).
(3) Disengage the blower motor wire harness from
the wire harness retainer.
(4) Unplug the blower motor wire harness connec-
tor from the HVAC housing wire harness.
(5) Remove the three screws that secure the
blower motor and blower wheel assembly to the
HVAC housing.
(6) Lower the blower motor and wheel assembly,
and cover, from the HVAC housing.
(7) Remove the blower wheel retainer clip and
remove the wheel from the blower motor shaft (Fig.
4).
INSTALLATION
(1) If installing the blower motor wheel only, press
the blower wheel hub onto the blower motor shaft.
Be sure the flat on the blower motor shaft is indexed
to the flat on the inside of the blower wheel hub.
(2) Install the retainer clip over the blower wheel
hub. The ears of the retainer clip must be indexed
over the flats on the blower motor shaft and blower
wheel hub.
Fig. 3 BLOWER MOTOR REMOVE/INSTALL
1 - BLOWER MOTOR HOUSING
2 - COOLING TUBE
3 - ELECTRICAL CONNECTOR
24 - 32 DISTRIBUTIONBR/BE
BLOWER MOTOR (Continued)

(1) Disconnect and isolate the battery negative
cable.
(2) If the vehicle is not equipped with air condi-
tioning, go to Step 6. If the vehicle is equipped with
air conditioning, recover the refrigerant from the sys-
tem. (Refer to 24 - HEATING & AIR CONDITION-
ING/PLUMBING - STANDARD PROCEDURE -
REFRIGERANT RECOVERY)
(3) Remove the instrument panel from the vehicle.
Refer to Instrument Panel System for the procedures.
(4) Disconnect the liquid line refrigerant line fit-
ting from the evaporator inlet tube. (Refer to 24 -
HEATING & AIR CONDITIONING/PLUMBING -
STANDARD PROCEDURE - A/C LINE COUPLERS)
Install plugs in, or tape over all of the opened refrig-
erant line fittings.
(5) Remove the accumulator. (Refer to 24 - HEAT-
ING & AIR CONDITIONING/PLUMBING/ACCU-
MULATOR - REMOVAL) Install plugs in, or tape
over all of the opened refrigerant line fittings.
(6) Drain the engine cooling system(Refer to 7 -
COOLING - STANDARD PROCEDURE) and (Refer
to 7 - COOLING - STANDARD PROCEDURE).
(7) Disconnect the heater hoses from the heater
core tubes. Refer to Cooling for the procedures.
Install plugs in, or tape over the opened heater core
tubes.
(8) Remove the Powertrain Control Module (PCM)
from the dash panel and set it aside, but do not
unplug the PCM wire harness connectors. Refer to
Electronic Control Modules for the procedures.
(9) Remove the nuts from the HVAC housing
mounting studs on the engine compartment side of
the dash panel.
(10) Remove the nuts that secure the HVAC hous-
ing to the mounting studs on the passenger compart-
ment side of the dash panel (Fig. 8).
(11) Pull the HVAC housing rearward far enough
for the mounting studs and the evaporator conden-
sate drain tube to clear the dash panel holes.
(12) Remove the HVAC housing from the vehicle.
REMOVAL - HVAC HOUSING INLET BAFFLE
(1) Remove the HVAC housing from the vehicle.
(Refer to 24 - HEATING & AIR CONDITIONING/
DISTRIBUTION/HVAC HOUSING - REMOVAL)
(2) Slide the HVAC housing inlet baffle (Fig. 9) all
the way to one side of the cowl plenum opening.
(3) Pull downwards sharply and firmly on the
opposite side of the HVAC housing inlet baffle to dis-
engage the snap features from the cowl plenum open-
ing.
(4) Remove the HVAC housing inlet baffle from the
cowl plenum panel.DISASSEMBLY
(1) Place the HVAC housing upside down on a
work bench.
(2) Remove the screw that secures the floor duct to
the bottom of the HVAC housing and slide the floor
duct off of the center heat duct adaptor.
(3) Unsnap the center heat duct adaptor from the
bottom of the HVAC housing and remove the screw
that was hidden by the adaptor.
(4) Remove the remaining screws on the bottom of
the HVAC housing that secure the two housing
halves together.
Fig. 8 HVAC HOUSING REMOVE/INSTALL
1 - BODY ASSEMBLY
2 - HVAC HOUSING
Fig. 9 HVAC HOUSING INLET BAFFLE REMOVE/
INSTALL
1 - RIGHT A-PILLAR
2 - INLET BAFFLE
3 - COWL PLENUM OPENING
BR/BEDISTRIBUTION 24 - 35
HVAC HOUSING (Continued)