2001 DODGE RAM heating

CONTROLS
DIAGNOSIS AND TESTING - VACUUM SYSTEM
Vacuum control is used to operate the mode doors
in the heater-only and HVAC housings. Testing of the
heater-only and a/c heater mode control switch oper-
ation will determine if the vacuum, electrical, and
mechanical controls are functioning. However, it is
possible that a vacuum control system that operates
perfectly at engine idle (high engine vacuum) may
not function properly at high engine speeds or loads
(low engine vacuum). This can be caused by leaks in
the vacuum system, or by a faulty or improperly
installed vacuum check valve.
A vacuum system test will help to identify the
source of poor vacuum system performance or vac-
uum system leaks. Before starting this test, stop the
engine and make certain that the problem is not a
disconnected vacuum supply tube at the engine vac-
uum source or the vacuum reservoir.
Use an adjustable vacuum test set (Special Tool
C-3707) and a suitable vacuum pump to test the
HVAC vacuum control system. With a finger placed
over the end of the vacuum test hose probe (Fig. 1),
adjust the bleed valve on the test set gauge to obtain
a vacuum of exactly 27 kPa (8 in. Hg.). Release and
block the end of the probe several times to verify that
the vacuum reading returns to the exact 27 kPa (8
in. Hg.) setting. Otherwise, a false reading will be
obtained during testing.
VACUUM CHECK VALVE
(1) Remove the vacuum check valve. On gasoline
engines, one valve is located in the vacuum supply
tube (black) at the intake manifold tap on the right
side of the engine. A second check valve is located
next to the tee fitting in the vacuum supply tube
(black) near the dash panel in the engine compart-
ment. On diesel engines, the vacuum check valve is
integral to the engine vacuum pump nipple and is
threaded into the vacuum pump. The vacuum check
valve must be removed in order to perform the fol-
lowing tests. (Refer to 24 - HEATING & AIR CONDI-
TIONING/CONTROLS/VACUUM CHECK VALVE -
REMOVAL)
(2) Connect the test set vacuum supply hose to the
a/c heater control side of the valve. When connected
to this side of the check valve, no vacuum should
pass and the test set gauge should return to the 27kPa (8 in. Hg.) setting. If OK, go to step Step 3. If
not OK, replace the faulty valve.
(3) Connect the test set vacuum supply hose to the
engine vacuum side of the valve. When connected to
this side of the check valve, vacuum should flow
through the valve without restriction. If not OK,
replace the faulty valve.
A/C HEATER CONTROLS
(1) Connect the test set vacuum probe to the
HVAC vacuum supply (black) tube in the engine com-
partment. Position the test set gauge so that it can
be viewed from the passenger compartment.
(2) Place the a/c heater mode control switch knob
to each mode position, one position at a time, and
pause after each selection. The test set gauge should
return to the 27 kPa (8 in. Hg.) setting shortly after
each selection is made. If not OK, a component or
vacuum line in the vacuum circuit of the selected
mode has a leak. See Locating Vacuum Leaks below.
CAUTION: Do not use lubricant on the switch ports
or in the holes in the plug, as lubricant will ruin the
vacuum valve in the switch. A drop of clean water
in the connector plug holes will help the connector
slide onto the switch ports.
Fig. 1 ADJUST VACUUM TEST BLEED VALVE
1 - VACUUM PUMP TOOL C-4289
2 - VACUUM TEST SET C-3707
3 - BLEED VALVE
4 - PROBE
24 - 10 CONTROLSBR/BE

the opposing friction surfaces and provide a higher
compressor clutch torque capability.
REMOVAL
The refrigerant system can remain fully-charged
during compressor clutch, pulley, or coil replacement.
The compressor clutch can be serviced in the vehicle.
(1) Disconnect and isolate the battery negative
cable.
(2) On models with the diesel engine option,
remove the compressor from the engine. Do not
remove the refrigerant lines or fittings. (Refer to 24 -
HEATING & AIR CONDITIONING/PLUMBING/A/C
COMPRESSOR - REMOVAL)
(3) Unplug the compressor clutch coil wire harness
connector.
(4) Insert the two pins of the spanner wrench
(Special Tool 6462 in Kit 6460) into the holes of the
clutch plate. Hold the clutch plate stationary and
remove the hex nut (Fig. 5).
(5) Remove the clutch plate and clutch shims. On
models with the diesel engine option, a puller (Spe-
cial Tool 6461 in Kit 6460) is used to remove the
clutch plate (Fig. 6). This compressor also uses a
shaft key, which must be removed.
(6) Remove the external front housing snap ring
with snap ring pliers (Fig. 7).
(7) Install the lip of the rotor puller (Special Tool
C-6141-1 in Kit 6460) into the snap ring groove
exposed in Step 6, and install the shaft protector
(Special Tool C-6141-2 in Kit 6460) (Fig. 8).
(8) Install the puller through-bolts (Special Tool
C-6461) through the puller flange and into the jaws
of the rotor puller and tighten (Fig. 9). Turn the
puller center bolt clockwise until the rotor pulley is
free.(9) Remove the screw and retainer from the clutch
coil lead wire harness on the compressor front hous-
ing (Fig. 10).
(10) Remove the snap ring from the compressor
hub and remove the clutch field coil (Fig. 11). Slide
the clutch field coil off of the compressor hub.
Fig. 5 CLUTCH NUT REMOVE
1 - FRONT PLATE SPANNER
Fig. 6 CLUTCH PULLER - DIESEL MODELS
1 - FRONT PLATE
2 - PULLER
Fig. 7 EXTERNAL SNAP RING REMOVE
1 - EXTERNAL SNAP RING
24 - 14 CONTROLSBR/BE
A/C COMPRESSOR CLUTCH (Continued)

NOTE: The air gap is determined by the spacer
shims. When installing an original, or a new clutch
assembly, try the original shims first. When install-
ing a new clutch onto a compressor that previously
did not have a clutch, use 1.0, 0.50, and 0.13 milli-
meter (0.040, 0.020, and 0.005 inch) shims from the
clutch hardware package that is provided with the
new clutch.
(12) On models with the diesel engine option,
install the compressor on the engine. (Refer to 24 -
HEATING & AIR CONDITIONING/PLUMBING/A/C
COMPRESSOR - INSTALLATION)(13) Connect the battery negative cable.
A/C COMPRESSOR CLUTCH
RELAY
DESCRIPTION
The a/c compressor clutch relay is a International
Standards Organization (ISO) micro-relay. The termi-
nal designations and functions are the same as a con-
ventional ISO relay. However, the micro-relay
terminal orientation (footprint) is different, the cur-
rent capacity is lower, and the relay case dimensions
are smaller than those of the conventional ISO relay.
OPERATION
The compressor clutch relay is a electromechanical
device that switches battery current to the compres-
sor clutch coil when the Powertrain Control Module
(PCM) grounds the coil side of the relay. The PCM
responds to inputs from the a/c heater control, the a/c
low pressure switch, and the a/c high pressure
switch.
The compressor clutch relay is located in the Power
Distribution Center (PDC) in the engine compart-
ment. Refer to the PDC label for relay identification
and location.
The compressor clutch relay cannot be repaired
and, if faulty or damaged, it must be replaced.
DIAGNOSIS AND TESTING - A/C COMPRESSOR
CLUTCH RELAY
RELAY TEST
The compressor clutch relay (Fig. 16) is located in
the Power Distribution Center (PDC). Refer to the
PDC label for relay identification and location.
Remove the relay from the PDC to perform the fol-
lowing tests:
(1) A relay in the de-energized position should
have continuity between terminals 87A and 30, and
no continuity between terminals 87 and 30. If OK, go
to Step 2. If not OK, replace the faulty relay.
(2) Resistance between terminals 85 and 86 (elec-
tromagnet) should be 7565 ohms. If OK, go to Step
3. If not OK, replace the faulty relay.
(3) Connect a battery to terminals 85 and 86.
There should now be continuity between terminals
30 and 87, and no continuity between terminals 87A
and 30. If OK, see the Relay Circuit Test below. If not
OK, replace the faulty relay.
RELAY CIRCUIT TEST
For circuit descriptions and diagrams, (Refer to
Appropriate Wiring Information).
Fig. 14 CLUTCH PLATE INSTALL
Fig. 15 CHECK CLUTCH AIR GAP
1 - FEELER GAUGE
BR/BECONTROLS 24 - 17
A/C COMPRESSOR CLUTCH (Continued)

tom of the a/c heater control panel. Refer to Heated
Mirrors for more information on this feature.
The heater-only or a/c heater control panel cannot
be repaired. If faulty or damaged, the entire unit
must be replaced. The control knobs and the illumi-
nation lamps are available for service replacement.
DIAGNOSIS AND TESTING - A/C HEATER
CONTROL
Satisfactory heater and air conditioner perfor-
mance depends upon proper operation and adjust-
ment of all operating controls and refrigeration
system components. For circuit descriptions and dia-
grams, (Refer to Appropriate Wiring Information).
These inspections, tests, and adjustments should be
used to locate the cause of a malfunction.
Operation must be tested as described in the fol-
lowing sequence:
(1) Inspect and adjust the serpentine drive belt.
Refer to Cooling for the procedures.
(2) Start the engine and hold the idle speed at
1,300 rpm.
(3) On vehicles with air conditioning, turn the
temperature control knob to the extreme counter-
clockwise (Cool) position, and set the mode control
switch knob to the Bi-Level (A/C) position. The out-
side (recirculation) air door should be open to outside
air. If not OK, (Refer to 24 - HEATING & AIR CON-
DITIONING/CONTROLS - DIAGNOSIS AND TEST-
ING - VACUUM SYSTEM).
(4) Open the vehicle windows. Test the blower
motor operation in all speeds. If not OK, (Refer to 24
- HEATING & AIR CONDITIONING/DISTRIBU-
TION/BLOWER MOTOR - DIAGNOSIS AND TEST-
ING).
(5) On vehicles with air conditioning, the compres-
sor should be running and the air conditioning sys-
tem in operation unless the ambient air temperature
is below about -1É C (30É F). If not OK, (Refer to 24 -
HEATING & AIR CONDITIONING - DIAGNOSIS
AND TESTING - A/C PERFORMANCE).
(6) Check the mode control switch operation. The
heater and air conditioner systems should respond as
described in the owner's manual in the vehicle glove
box to each mode selected. Reduce the engine speed
to normal idle. The vacuum will be high at low idle
and the vacuum actuators should respond quickly. If
not OK, (Refer to 24 - HEATING & AIR CONDI-
TIONING/CONTROLS - DIAGNOSIS AND TEST-
ING - VACUUM SYSTEM).
(7) If the vacuum tests, and the electrical compo-
nent and circuit tests reveal no problems, disassem-
ble the HVAC housing to inspect for mechanical
misalignment or binding of the mode doors. (Refer to
24 - HEATING & AIR CONDITIONING/DISTRIBU-
TION/HVAC HOUSING - DISASSEMBLY)
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) Reach under the instrument panel near the
driver side of the floor panel transmission tunnel and
unplug the a/c heater control to HVAC housing vac-
uum harness connector.
(3) While still reaching under the instrument
panel, disengage the retainer on the a/c heater con-
trol half of the vacuum harness from the hole in the
center distribution duct (Fig. 18).
(4) Remove the cluster bezel from the instrument
panel. Refer to Instrument Panel System for the pro-
cedures.
Fig. 18 A/C HEATER CONTROL VACUUM HARNESS
ROUTING
1 - A/C HEATER CONTROL VACUUM HARNESS
2 - REINFORCEMENT
3 - RETAINER
4 - CENTER DISTRIBUTION DUCT
BR/BECONTROLS 24 - 19
A/C HEATER CONTROL (Continued)

REMOVAL
(1) Disconnect and isolate the battery negative
cable.
(2) Unplug the wire harness connector from the a/c
high pressure switch, which is mounted to a fitting
on the discharge line between the compressor and
the condenser inlet.
(3) Unscrew the a/c high pressure switch from the
discharge line fitting.
(4) Remove the a/c high pressure switch from the
vehicle.
(5) Remove the O-ring seal from the discharge line
fitting and discard.
INSTALLATION
(1) Lubricate a new O-ring seal with clean refrig-
erant oil and install it on the discharge line fitting.
Use only the specified O-rings as they are made of a
special material for the R-134a system. Use only
refrigerant oil of the type recommended for the com-
pressor in the vehicle. (Refer to 24 - HEATING &
AIR CONDITIONING/PLUMBING/REFRIGERANT
OIL - DESCRIPTION)
(2) Install and tighten the high pressure cut-off
switch on the discharge line fitting. The switch
should be hand-tightened onto the discharge line fit-
ting.
(3) Plug the wire harness connector into the high
pressure cut-off switch.
(4) Connect the battery negative cable.
A/C LOW PRESSURE SWITCH
DESCRIPTION
The a/c low pressure switch is located on the top of
the accumulator. The switch is screwed onto an accu-
mulator fitting that contains a Schrader-type valve,
which allows the switch to be serviced without dis-
charging the refrigerant system. The accumulator fit-
ting is equipped with an O-ring to seal the switch
connection.
OPERATION
The a/c low pressure switch is connected in series
electrically with the a/c high pressure switch and the
a/c heater control, between ground and the Power-
train Control Module (PCM). The switch contacts
open and close causing the PCM to turn the compres-
sor clutch on and off. This regulates the refrigerant
system pressure and controls evaporator tempera-
ture. Controlling evaporator temperature prevents
condensate water on the evaporator fins from freez-
ing and obstructing air conditioning system air flow.
The a/c low pressure switch contacts are open
when the suction pressure is about 152-165 kPa(22-24 psi) or lower. The switch contacts will close
when the suction pressure rises to about 255-296 kPa
(37-43 psi) or above. Lower ambient temperatures,
below about -1É C (30É F), will also cause the switch
contacts to open. This is due to the pressure/temper-
ature relationship of the refrigerant in the system.
The a/c low pressure switch is a factory-calibrated
unit. It cannot be adjusted or repaired and, if faulty
or damaged, it must be replaced.
DIAGNOSIS AND TESTING - A/C LOW
PRESSURE SWITCH
Before performing diagnosis of the a/c low pressure
switch, be certain that the switch is properly
installed on the accumulator fitting. If the switch is
too loose it may not open the Schrader-type valve in
the accumulator fitting, which will prevent the
switch from correctly monitoring the refrigerant sys-
tem pressure. Also verify that the refrigerant system
has the correct refrigerant charge. (Refer to 24 -
HEATING & AIR CONDITIONING - DIAGNOSIS
AND TESTING - A/C PERFORMANCE)
Remember that lower ambient temperatures, below
about -1É C (30É F), during cold weather will open the
switch contacts and prevent compressor operation
due to the pressure/temperature relationship of the
refrigerant. For circuit descriptions and diagrams,
(Refer to Appropriate Wiring Information).
(1) Disconnect and isolate the battery negative
cable.
(2) Unplug the a/c low pressure switch wire har-
ness connector from the switch on the accumulator
fitting.
(3) Install a jumper wire between the two cavities
of the a/c low pressure switch wire harness connector.
(4) Connect a manifold gauge set to the refrigerant
system service ports. (Refer to 24 - HEATING & AIR
CONDITIONING/PLUMBING - STANDARD PRO-
CEDURE - REFRIGERANT SYSTEM SERVICE
EQUIPMENT)
(5) Connect the battery negative cable.
(6) Place the a/c heater mode control switch knob
in any A/C position and start the engine.
(7) Check for continuity between the two terminals
of the low pressure cycling clutch switch. There
should be continuity with a suction pressure reading
of 296 kPa (43 psi) or above, and no continuity with a
suction pressure reading of 172 kPa (25 psi) or below.
If OK, test and repair the A/C switch sense circuit as
required. If not OK, replace the faulty switch.
REMOVAL
(1) Disconnect and isolate the battery negative
cable.
BR/BECONTROLS 24 - 21
A/C HIGH PRESSURE SWITCH (Continued)

(2) Unplug the wire harness connector from the a/c
low pressure switch on the top of the accumulator
(Fig. 20).
(3) Unscrew the a/c low pressure switch from the
fitting on the top of the accumulator.
(4) Remove the O-ring seal from the accumulator
fitting and discard.
INSTALLATION
(1) Lubricate a new O-ring seal with clean refrig-
erant oil and install it on the accumulator fitting.
Use only the specified O-rings as they are made of a
special material for the R-134a system. Use only
refrigerant oil of the type recommended for the com-
pressor in the vehicle. (Refer to 24 - HEATING &
AIR CONDITIONING/PLUMBING/REFRIGERANT
OIL - DESCRIPTION)
(2) Install and tighten the a/c low pressure switch
on the accumulator fitting. The switch should be
hand-tightened onto the accumulator fitting.
(3) Plug the wire harness connector into the a/c
low pressure switch.
(4) Connect the battery negative cable.
BLOWER MOTOR RELAY
DESCRIPTION
The blower motor relay is an International Stan-
dards Organization (ISO)-type relay. The relay is an
electromechanical device that switches battery cur-
rent from a fuse in the Power Distribution Center
(PDC) directly to the blower motor. The relay is ener-
gized when the relay coil is provided a voltage signal
by the ignition switch. This arrangement reduces the
amount of battery current that must flow through
the ignition switch.
OPERATION
The blower motor relay control circuit is protected
by a fuse located in the junction block. When the
relay is de-energized, the blower motor receives no
battery current.
The blower motor relay is located in the PDC in
the engine compartment. Refer to the PDC label for
blower motor relay identification and location.
The blower motor relay cannot be repaired and, if
faulty or damaged, it must be replaced.
DIAGNOSIS AND TESTING - BLOWER MOTOR
RELAY
RELAY TEST
The blower motor relay (Fig. 21) is located in the
Power Distribution Center (PDC). Remove the blower
motor relay from the PDC to perform the following
tests:
(1) A relay in the de-energized position should
have continuity between terminals 87A and 30, and
no continuity between terminals 87 and 30. If OK, go
to Step 2. If not OK, replace the faulty relay.
(2) Resistance between terminals 85 and 86 (elec-
tromagnet) should be 7565 ohms. If OK, go to Step
3. If not OK, replace the faulty relay.
(3) Connect a battery to terminals 85 and 86.
There should now be continuity between terminals
30 and 87, and no continuity between terminals 87A
and 30. If OK, see Relay Circuit Test below. If not
OK, replace the faulty relay.
RELAY CIRCUIT TEST
For circuit descriptions and diagrams, (Refer to
Appropriate Wiring Information).
(1) The relay common feed terminal cavity (30) is
connected to fused battery feed directly from a fuse
in the Power Distribution Center (PDC), and should
be hot at all times. Check for battery voltage at the
PDC cavity for relay terminal 30. If OK, go to Step 2.
If not OK, repair the open circuit to the PDC fuse as
required.
Fig. 20 ACCUMULATOR AND A/C LOW PRESSURE
SWITCH
1 - CLIP
2 - BRACKET
3 - SCREW
4 - BAND
5 - ACCUMULATOR
6 - TO SUCTION LINE
7 - A/C LOW PRESSURE SWITCH
8 - FROM EVAPORATOR OUTLET
24 - 22 CONTROLSBR/BE
A/C LOW PRESSURE SWITCH (Continued)

motor speeds, but can only be turned off by selecting
the Off position with the heater-only or a/c heater
control switch knob.
OPERATION
The blower motor switch directs the blower motor
ground path through the mode control switch to the
blower motor resistor, or directly to ground, as
required to achieve the selected blower motor speed.
The blower motor switch cannot be repaired and, if
faulty or damaged, the entire heater-only or a/c
heater control unit must be replaced. The blower
motor switch knob is serviced separately.
DIAGNOSIS AND TESTING - BLOWER MOTOR
SWITCH
For circuit descriptions and diagrams, (Refer to
Appropriate Wiring Information).
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) Check for battery voltage at the fuse in the
Power Distribution Center (PDC). If OK, go to Step
2. If not OK, repair the shorted circuit or component
as required and replace the faulty fuse.
(2) Turn the ignition switch to the Off position.
Disconnect and isolate the battery negative cable.
Remove the a/c heater control from the instrument
panel. (Refer to 24 - HEATING & AIR CONDITION-
ING/CONTROLS/A/C HEATER CONTROL -
REMOVAL) Check for continuity between the ground
circuit cavity of the a/c heater control wire harness
connector and a good ground. There should be conti-
nuity. If OK, go to Step 3. If not OK, repair the open
circuit to ground as required.
(3) With the a/c heater control wire harness con-
nector unplugged, place the a/c heater mode control
switch knob in any position except the Off position.
Check for continuity between the ground circuit ter-
minal and each of the blower motor driver circuit ter-
minals of the a/c heater control as you move the
blower motor switch knob to each of the four speed
positions. There should be continuity at each drivercircuit terminal in only one blower motor switch
speed position. If OK, test and repair the blower
driver circuits between the a/c heater control connec-
tor and the blower motor resistor as required. If not
OK, replace the faulty a/c heater control unit.
REMOVAL
The blower motor switch cannot be repaired and, if
faulty or damaged, the entire heater-only or a/c
heater control unit must be replaced. (Refer to 24 -
HEATING & AIR CONDITIONING/CONTROLS/A/C
HEATER CONTROL - REMOVAL) The blower motor
switch knob is serviced separately.
BLEND DOOR ACTUATOR
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) Turn the ignition switch to the run position.
(2) Locate the temperature control knob in the mid
(12 o'clock) position.
(3) Turn the ignition switch to the off position.
(4) Disconnect and isolate the battery negative
cable.
(5) Remove the instrument panel from the vehicle.
Refer to Instrument Panel System for the procedures.
(6) Remove the HVAC housing from the vehicle.
(Refer to 24 - HEATING & AIR CONDITIONING/
DISTRIBUTION/HVAC HOUSING - REMOVAL)
(7) Unplug the wire harness connector from the
blend door actuator (Fig. 24).
(8) Remove the two mounting screws which secure
the actuator to the housing.
(9) Slide the blend door actuator off the blend door
shaft.
NOTE: A black plastic coupler may be attached to
the blend door shaft. Remove the coupler and
inspect for damage. Reinstall if there is no damage
found.
BR/BECONTROLS 24 - 25
BLOWER MOTOR SWITCH (Continued)

INSTALLATION
NOTE: Before installing the blend door actuator, be
certain that the blend door is not binding and is
capable of full travel in both directions.
(1) Align the actuator with the blend door shaft
and rotate the actuator to align it to the mounting
bosses on the HVAC housing.
(2) Align and install the actuator screws. Tighten
the mounting screws to 2.2 N´m (20 in. lbs.).
(3) Plug in the wire harness connector to the blend
door actuator.
(4) Install the HVAC housing in the vehicle. (Refer
to 24 - HEATING & AIR CONDITIONING/DISTRI-
BUTION/HVAC HOUSING - INSTALLATION)
(5) Install the instrument panel in the vehicle.
Refer to Instrument Panel System for the procedures.
(6) Make sure the Temperature Control Knob is in
the mid (12 o'clock) position to allow the actuator to
automatically position itself in the mid position and
come to a complete stop when powered up.
(7) Connect the battery negative cable.
MODE DOOR ACTUATOR
REMOVAL - HEAT/DEFROST DOOR ACTUATOR
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 HVAC housing from the vehicle
and place it on a work bench. (Refer to 24 - HEAT-
ING & AIR CONDITIONING/DISTRIBUTION/HVAC
HOUSING - REMOVAL)
(3) Unplug the two vacuum harness connectors
from the heat/defrost door actuator (Fig. 25).
(4) Using a trim stick or another suitable wide
flat-bladed tool, gently pry the heat/defrost door
crank arm off the heat/defrost door pivot.
(5) Remove the two screws that secure the heat/de-
frost door actuator to the HVAC housing.
(6) Remove the heat/defrost door actuator from the
HVAC housing.
Fig. 24 BLEND DOOR ACTUATOR REMOVE/
INSTALL
1 - DUCT
2 - MOUNTING SCREWS
3 - UNIT HOUSING
4 - HARNESS AND CONNECTOR
5 - BLEND DOOR ACTUATOR
Fig. 25 HEAT/DEFROST DOOR ACTUATOR
1 - VACUUM LINE
2 - DOOR PIVOT CONNECTION
3 - HEAT/DEFROST DOOR ACTUATOR
24 - 26 CONTROLSBR/BE
BLEND DOOR ACTUATOR (Continued)