heater DODGE NEON 2000 Service Manual PDF

HEATER-A/C VACUUM SYSTEM DIAGNOSIS
CONDITION POSSIBLE CAUSES CORRECTION
NO FORCED AIR IN
HEAT POSITION1. Vacuum line pinched or
leaking.
2. Faulty heat defroster or
mode door.
3. Faulty selector switch.
4. Vacuum check valve.1. Locate and repair vacuum leak or pinched line.
2. Test actuators and door operation. Repair as
necassary.
3. Test selector switch and replace if necessary.
4. Test check valve and replace if necessary.
NO FORCED AIR IN
PANEL POSITION1. Vacuum line pinched or
leaking.
2. Faulty mode door.
3. Faulty selector switch.
4. Vacuum check valve.1. Locate and repair vacuum leak or pinched line.
2. Test actuator and door operation. Repair as
necessary.
3. Test selector switch and replace if necessary.
4. Test check valve and replace if necessary.
NO FORCED AIR IN
DEFROST POSITION1. Vacuum line pinched or
leaking.
2. Faulty heat, defroster, or
mode door.
3. Faulty selector switch.
4. Vacuum check valve.1. Locate and repair vacuum leak or pinched line.
2. Test actuators and door operation. Repair as
necessary.
3. Test selector switch and replace if necessary.
4. Test check valve and replace if necessary.
ONE-WAY CHECK VALVE
(1) Disconnect the heater-A/C vacuum supply
(Black) tube in the engine compartment. This tube
passes through an opening in the dash panel.
(2) Remove the one-way vacuum check valve. The
valve is located on the (Black) vacuum supply hose at
the brake power booster.
(3) Connect the test set vacuum supply hose to the
heater 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 27 kPa (8 in. Hg.)
setting. If OK, go to step Step 4. If not OK, replace
the faulty valve.
(4) 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.
HEATER-A/C CONTROLS
The operation of the Circulation door can be
viewed by removing the blower motor and looking up
into the unit inlet. See Blower Motor Wheel and
Assembly removal and installation in this section for
service procedures.
(1) Connect the test set vacuum probe to the heat-
er-A/C vacuum supply (Black) hose in the engine
compartment. Position the test set gauge so that it
can be viewed from the passenger compartment.
(2) Start with the Mode control in the Panel posi-
tion and the Circulation control in the Outside-air
position.
(3) Move the Circulation control to the Recircula-
tion position (the Circulation door should move intothe Recirculation position). After a short pause move
the Mode control to the Defrost position (the Circula-
tion door should move to the Outside-air position).
The test gauge should return to the calibrated set-
ting of 27 kPa (8 in. Hg.) after each selection is
made. If the gauge cannot achieve the calibrated set-
ting, the vacuum circuit or a component has a leak.
(4) If the gauge achieves the calibrated setting but
the door does not move, there is either a pinched vac-
uum line or a failed actuator.
LOCATING VACUUM LEAKS
(1) Connect the test vacuum probe to the vehicles
(Black) supply hose. Position the vacuum test gauge
so it can be viewed from the passenger compartment.
(2) Place the Mode in the Panel position and the
Circulation control in the Recirculation position.
(3) Remove the center instrument panel bezel.
(4) Remove the center vent duct.
(5) Remove and block the Supply (Black) vacuum
line at the control. The test gauge should return to
the calibrated setting of 27 kPa (8 in. Hg). If not,
there is a leak in the Supply line.
(6) If there is no leak in the Supply line, reconnect
it to the Control and remove the Actuator Feed (Red)
line from the Control. Block the vacuum connection
on the Control from where the line was removed. The
test gauge should return to the calibrated setting of
27 kPa (8 in. Hg.). If not, there is a leak in the Con-
trol.
(7) If there is no leak in the Supply line or the
Control, reconnect the Actuator Feed (Red) line to the
control. Remove and block the Actuator Feed (Red)
line at the Actuator. The actuator vacuum port is
accessible behind and above the Glove Box. The test
24 - 16 HEATING AND AIR CONDITIONINGPL
DIAGNOSIS AND TESTING (Continued)

obtained, add or subtract shims until desired read-
ing is obtained.
(8) Install compressor shaft bolt. Tighten to 17.56
2 N´m (155620 in. lbs.) torque.
NOTE: Shims may compress after tightening shaft
nut. Check air gap in four or more places to verify if
air gap is still correct. Spin pulley for final check.
CLUTCH BREAK-IN
After new clutch installation, cycle the A/C clutch
20 times (5 seconds on and 5 seconds off). During
this procedure, set the system to the A/C mode,
engine rpm at 1500 - 2000, and high blower speed.
This procedure (burnishing) will seat the opposing
friction surfaces and provide a higher clutch torque
capability.
CONDENSATION DRAIN TUBE
REMOVAL
(1) Raise vehicle.
(2) Locate rubber drain tube on right side of dash
panel (Fig. 30).
(3) Squeeze clamp and remove drain tube.
INSTALLATION
To install, reverse the preceding operation. Check
the drain tube nipple on the heater-A/C housing for
any obstructions.
CONDENSER
The condenser is located in front of the engine
radiator. It has no serviceable parts. If damaged or
leaking, the condenser assembly must be replaced.
WARNING: THE REFRIGERANT MUST BE
REMOVED FROM THE SYSTEM BEFORE REMOV-
ING THE CONDENSER.
REMOVAL
(1) Using a R-134a refrigerant recovery machine,
remove the refrigerant from the A/C system.
(2) Remove battery support strut.
(3) Remove refrigerant lines from condenser (Fig.
31).
(4) Remove upper radiator mounts.
(5) Remove condenser to radiator mounting
screws.
(6) Tilt radiator back and remove condenser.
INSTALLATION
For installation, reverse the above procedures.
²Tighten the condenser refrigerant lines to 5 N´m
(45 in lbs).
Fig. 29 Installing Pulley Assembly
1 ± PULLEY ASSEMBLY
2 ± WOOD BLOCK
Fig. 30 Condensate Water Drain Tube ± Typical
1 ± DASH PANEL (UNDER HOOD RIGHT SIDE)
2 ± CLAMP
3 ± CONDENSATE DRAIN TUBE
4 ± NIPPLE-A/C HEATER HOUSING
PLHEATING AND AIR CONDITIONING 24 - 25
REMOVAL AND INSTALLATION (Continued)

DISCHARGE LINE
WARNING: THE REFRIGERANT SYSTEM MUST BE
RECOVERED BEFORE SERVICING ANY PART OF
THE REFRIGERANT SYSTEM.
REMOVAL
(1) Using a R-134a refrigerant recovery machine,
remove the refrigerant from A/C system.
(2) From the top side of the vehicle, remove line at
compressor (Fig. 32).
(3) From the bottom side of the vehicle, remove
line at condenser.
INSTALLATION
For installation, reverse the above procedures.
EVAPORATOR
This vehicle uses an aluminum plate and fin style
evaporator. It is located in the Evaporator/Blower
module.
The unit housing must be removed from the vehi-
cle before beginning with this procedure. Refer to
Unit Housing in this section for removal procedure.
Use this procedure if any or all of the following
items require service:
²Evaporator
²Air inlet duct
²Heater Core
²Heating and Air Conditioning
DISASSEMBLE
(1) Separate the foam seals at the evaporator line
connection, and the dash panel air distribution out-
lets (Fig. 33).
(2) Disconnect fin sensing probe from harness.
(3) Remove upper to lower case retaining clip and
screws.
(4) Separate the case halves (Fig. 34).
(5) Lift the evaporator out of the module (Fig. 35).
ASSEMBLE
To reassemble, reverse the above procedures.
EVAPORATOR PROBE
The evaporator probe can be removed without
removing the Unit Housing from the vehicle.
REMOVAL
(1) Disconnect probe wiring connector from behind
the glove box.
(2) Remove rubber grommet from evaporator/
blower module (Fig. 36).
(3) Note which of the three pilot holes the evapo-
rator probe is located in.
(4) Pull probe out of evaporator fins.
INSTALLATION
(1) There are three pilot holes available for the
probe. The top hole is for service. If top hole was not
used by previous probe, install probe in top hole.
(2) If previous probe was removed from top hole,
use a small plastic stick of approximately 1/8 inch
Fig. 31 Condenser Refrigerant Lines
1 ± LIQUID LINE
2 ± A/C LINE MOUNTING BOLTS
3 ± DISCHARGE LINE
4 ± CONDENSER
Fig. 32 Discharge Line
1 ± DISCHARGE LINE
2 ± A/C COMPRESSOR
3 ± HIGH PRESSURE CUT OUT SWITCH
4 ± SUCTION LINE
24 - 26 HEATING AND AIR CONDITIONINGPL
REMOVAL AND INSTALLATION (Continued)

diameter, and make a new hole. Make the hole 1/4
inch above, or below the original hole in the evapora-
tor core.(3) Insert new probe into hole between evaporator
fins.
(4) Reinstall rubber grommet into evaporator
probe access hole.
EXPANSION VALVE
WARNING: THE REFRIGERATION SYSTEM MUST
BE COMPLETELY EMPTY BEFORE PROCEEDING
WITH THIS OPERATION.
Fig. 33 Lower HVAC Housing
1 ± EVAPORATOR AND CONNECTION
2 ± FOAM SEALS
3 ± HEATER CORE AND TUBES
4 ± HVAC HOUSING LOWER CASE
5 ± HOUSING MOUNTING STUDS
6 ± HOUSING DRAIN
7 ± WIRING
8 ± BLOWER MOTOR AND WHEEL
Fig. 34 Case Separation - Typical
1 ± CASE HALVES
2 ± EVAPORATOR
3 ± BLOWER WHEEL
Fig. 35 Evaporator Removal - Typical
1 ± EVAPORATOR
2 ± BLOWER WHEEL
Fig. 36 Evaporator Probe Location - Typical
1 ± EVAPORATOR PROBE WIRING CONNECTOR
2 ± EVAPORATOR PROBE RUBBER GROMMET
3 ± EVAPORATOR/BLOWER MODULE
PLHEATING AND AIR CONDITIONING 24 - 27
REMOVAL AND INSTALLATION (Continued)

REMOVAL
(1) Remove the wire connector from the low pres-
sure cut-off switch.
(2) Remove the center bolt of refrigerant line
plumbing sealing plate (Fig. 37).
(3) Carefully pull the refrigerant line-sealing plate
assembly from the expansion valve towards front of
vehicle. Do not scratch the expansion valve sealing
surfaces with pilot tubes.
(4) Cover the openings on A/C line-sealing plate
assembly to prevent contamination.
(5) Remove two screws securing the expansion
valve to the evaporator sealing plate.
(6) Carefully remove valve.
INSTALLATION
(1) Remove and replace the aluminum gasket on
the evaporator sealing plate.
(2) Carefully hold the expansion valve to the evap-
orator sealing plate so not to scratch the sealing sur-
face. Install two screws and tighten to 1163 N´m
(100630 in. lbs.).
(3) Remove and replace the aluminum gasket on
the refrigerant line- sealing plate assembly.
(4) Carefully hold the refrigerant line-sealing plate
assembly to the expansion valve. Install bolt and
tighten to 2363 N´m (200630 in. lbs.).
(5) Connect wires to low pressure cut-off switch.
(6) Evacuate and recharge system.
(7) After expansion valve is installed, system is
charged, and leaks have been checked, repeat A/C
performance check.
HEATER CORE
Refer to HVAC Housing Disassembly and Assembly
in this section for heater core removal procedure.
HEATER HOSES
CAUTION: When removing hoses from heater core
inlet or outlet nipples DO NOT exert excess pres-
sure. The heater core may become damaged and
leak engine coolant.
NOTE: Review Cooling System Precautions before
proceeding with this operation.
REMOVAL
(1) Drain engine cooling system. Refer to Group 7,
Cooling System.
(2) Using spring tension clamp pliers, remove
clamps at end of heater hose to be removed (Fig. 38).
(3) Carefully rotate hose back and forth while pull-
ing away from connector nipple.INSTALLATION
For installation, reverse the above procedures.
Fig. 37 Expansion Valve - Typical
1 ± ALUMINUM N-GASKET
2 ± PLUMBING SEALING PLATE
3 ± LOW/DIFFERENTIAL PRESSURE CUT-OFF SWITCH
4 ± DASH PANEL
5 ± H-VALVE
6 ± EVAPORATOR SEALING PLATE
7 ± H-VALVE
Fig. 38 Heater Hoses and Clamps
1 ± COWL PANEL
2 ± HEATER HOSE AND CLAMPS
3 ± HEATER CORE TUBES
4 ± HEATER HOSE SUPPLY AND RETURN TUBES
24 - 28 HEATING AND AIR CONDITIONINGPL
REMOVAL AND INSTALLATION (Continued)

INSTALLATION
NOTE: Verify the O-ring condition on the replace-
ment switch.
For installation, reverse the above procedures.
Evacuate and charge the system.
MODE CONTROL CABLE
The Mode Control Cable can be removed and
installed without having to remove the instrument
panel from the vehicle.
REMOVAL
(1) Remove instrument panel center stack bezel
(Fig. 41).
(2) Remove center air duct (Fig. 42).
(3) Remove heater-A/C control head and disconnect
cable (Fig. 43).
(4) Disconnect cable at heater unit.
(5) Remove cable from vehicle.
INSTALLATION
For installation, reverse the above procedures,
adjust cable and test. Refer to Mode Control Cable
Adjustment at the end of this section.
Fig. 40 Expansion Valve and Low Pressure Cut-Off
Switch
1 ± EXPANSION VALVE
2 ± LOW PRESSURE CUTOFF SWITCH
3 ± LIQUID LINE
4 ± SUCTION LINE
Fig. 41 Instrument Panel Center Bezel & Knobs
1 ± INSTRUMENT PANEL CENTER AIR DUCT
2 ± OUTSIDE AIR/RECIRC CONTROL KNOB
3 ± MODE CONTROL KNOB
4 ± BLOWER SPEED KNOB
5 ± TEMPERATURE CONTROL KNOB
Fig. 42 HVAC Center Air Duct & Control Head
1 ± CENTER AIR DUCT
2 ± INSTRUMENT PANEL
3 ± HVAC CONTROL HEAD
4 ± ATTACHING SCREWS
24 - 30 HEATING AND AIR CONDITIONINGPL
REMOVAL AND INSTALLATION (Continued)

(3) Remove line at expansion valve.
(4) Remove line at compressor (Fig. 46).
INSTALLATION
For installation, reverse the above procedures.
TEMPERATURE CONTROL CABLE
The Control Cable can be removed and installed
without having to remove the instrument panel from
the vehicle.
REMOVAL
(1) Remove instrument panel center stack bezel
(Fig. 41).
(2) Remove heater-A/C control head (Fig. 42).
(3) Remove center air duct.
(4) Disconnect cable at control panel. Remove con-
trol from instrument panel.
(5) Disconnect cable at heater unit (Fig. 47).
(6) Remove cable from vehicle.
INSTALLATION
For installation, reverse the above procedures,
adjust cable and test. See Temperature Control Cable
Adjustment in this section.
UNIT HOUSING
The instrument panel must be removed in order to
remove the Unit Housing. Refer to group 8E Instru-
ment Panel and Systems for detailed procedure.
WARNING: THE R-134a REFRIGERANT SYSTEM
MUST BE RECOVERED BEFORE SERVICING ANY
PART OF THE REFRIGERANT SYSTEM.
REMOVAL
(1) Using a refrigerant recovery machine, remove
the refrigerant from the A/C system, if equipped.
(2) Remove instrument panel from vehicle. Refer
to group 8E Instrument Panel and Systems for
detailed procedure.
(3) Drain cooling system and remove heater hoses
at the dash panel. Place plugs in the heater core out-
lets to prevent coolant spillage during unit housing
removal.
(4) Unfasten coolant recovery container and set
aside.
(5) Remove suction line at expansion valve. Cap
open refrigerant lines to prevent moisture and/or dirt
from entering.
Fig. 46 A/C Compressor Suction Line
1 ± FILTER DRIER
2 ± SERVICE PORTS
3 ± FILTER DRIER MOUNTING GROMMET
4 ± EVAPORATOR LINE BLOCK
5 ± EXPANSION VALVE
6 ± LOW PRESSURE CUT OUT SWITCH CONNECTOR
7 ± HVAC HOUSING DRAIN OUTLET
8 ± CONDENSATE DRAIN TUBE
9 ± EXPANSION VALVE SCREWS
10 ± CONDENSER LIQUID LINE
11 ± COMPRESSOR SUCTION LINE
Fig. 47 HVAC Housing Cables
1 ± VACUUM HARNESS
2 ± DOOR CAM
3 ± HVAC UPPER HOUSING
4 ± HVAC CONTROL HEADS CABLES
5 ± MODE DOOR LEVERS
6 ± DEFROSTER DUCT OUTLET
24 - 32 HEATING AND AIR CONDITIONINGPL
REMOVAL AND INSTALLATION (Continued)

(6) Remove expansion valve from evaporator, and
cap fittings.
(7) Remove rubber drain tube extension from con-
densation drain tube.
(8) Disconnect the vacuum harness at the power
brake booster (Fig. 48).
(9) Unsnap and remove the defroster duct (Fig.
49).(10) Remove three retaining nuts located in the
engine compartment, on the dash panel (Fig. 50).
(11) Remove the right side retaining screw (Fig.
51).
(12) Remove remaining nut located on dash panel
stud.
(13) Disconnect the wiring connectors.
(14) Remove assembly from the vehicle.
Fig. 48 HVAC Vacuum Harness
1 ± BRAKE POWER BOOSTER
2 ± A/C VACUUM CHECK VALVE
3 ± VACUUM HARNESS
Fig. 49 HVAC Housing Defroster Duct
1 ± DEFROSTER DUCT
2 ± BODY
3 ± ELECTRICAL CONNECTOR
4 ± HVAC HOUSING
Fig. 50 Dash Panel Retaining Studs
1 ± BLOWER RESISTOR
2 ± EXPANSION VALVE
3 ± DRAIN TUBE
4 ± DASH PANEL
5 ± HEATER HOSES
6 ± RETAINING STUDS
Fig. 51 Housing Screws
1 ± RIGHT SIDE RETAINING SCREW
2 ± EVAPORATOR PROBE GROMMET
3 ± SCREW BOSSES
4 ± DASH PANEL STUD AND NUT
PLHEATING AND AIR CONDITIONING 24 - 33
REMOVAL AND INSTALLATION (Continued)

INSTALLATION
For installation, reverse the above procedures.
DISASSEMBLY AND ASSEMBLY
HEATER-A/C HOUSING
Use this procedure if any or all of the following
items require service:
²Heater core
²Evaporator
²HVAC housing
The HVAC housing must be removed from the
vehicle before beginning with this procedure. Refer to
Unit Housing in this section for removal procedure.
DISASSEMBLY
(1) Separate the air distribution outlet foam seals
at the case parting line (Fig. 52).
(2) Remove the evaporator lines foam seal, and
heater core tubes foam seal from the unit (Fig. 53).
(3) Remove the retaining clips and screws that
hold the upper and lower housings together.
(4) Separate the two halves of the housing.
(5) Lift the heater core/evaporator out of the case.
ASSEMBLY
To reassemble, reverse the above procedures.
ADJUSTMENTS
MODE CONTROL CABLE
(1) Engage cable to actuator arm lever on mode
door and attach to housing (Fig. 47).
(2) Attach other end of cable to instrument panel
control (Fig. 43).
(3) Turn the mode knob completely counterclock-
wise.
(4) While holding the knob in the counterclockwise
position, pull on the gray casing of the mode cable.
This will take up any free play in the cable and index
the mode door to the mode knob.
(5) Then snap the cable hold down clip into posi-
tion.
TEMPERATURE CONTROL CABLE
(1) Engage cable to actuator arm on temperature
door and attach to housing (Fig. 47).
(2) Attach other end of cable to instrument panel
control (Fig. 43).
(3) Turn the temperature knob completely counter-
clockwise.
Fig. 52 HVAC Housing Air Distribution Foam Seals
1 ± AIR DISTRIBUTION
2 ± RECIRCULATION DOOR VACUUM ACTUATOR
3 ± AIR INLET
4 ± BLOWER MOTOR
5 ± EVAPORATOR PROBE CONNECTOR
6 ± CONTROL CABLES
7 ± VACUUM HARNESS
Fig. 53 HVAC Housing Evaporator Connection and
Heater Core Tube Seals
1 ± EVAPORATOR AND CONNECTION
2 ± FOAM SEALS
3 ± HEATER CORE AND TUBES
4 ± HVAC HOUSING LOWER CASE
5 ± HOUSING MOUNTING STUDS
6 ± HOUSING DRAIN
7 ± WIRING
8 ± BLOWER MOTOR AND WHEEL
24 - 34 HEATING AND AIR CONDITIONINGPL
REMOVAL AND INSTALLATION (Continued)

HEATING AND AIR CONDITIONING
TABLE OF CONTENTS
page page
REMOVAL AND INSTALLATION
EVAPORATOR CORE ± R. H. D...............1
HEATER CORE ± R. H. D....................3SPECIFICATIONS
TORQUE SPECIFICATIONS..................6
REMOVAL AND INSTALLATION
EVAPORATOR CORE ± R. H. D.
REMOVAL
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, REFER TO GROUP 8M ± PASSIVE
RESTRAINT SYSTEMS BEFORE ATTEMPTING ANY
STEERING WHEEL, STEERING COLUMN, OR
INSTRUMENT PANEL COMPONENT DIAGNOSIS OR
SERVICE. FAILURE TO TAKE THE PROPER PRE-
CAUTIONS COULD RESULT IN ACCIDENTAL AIR-
BAG DEPLOYMENT AND POSSIBLE PERSONAL
INJURY.
WARNING: DO NOT OPEN THE RADIATOR DRAIN-
COCK OR DISCONNECT COOLANT HOSES WHEN
THE COOLING SYSTEM IS HOT AND UNDER PRES-
SURE. SERIOUS BURNS FROM COOLANT CAN
OCCUR.
WARNING: READ ALL SAFETY PRECAUTIONS AND
WARNINGS BEFORE PROCEEDING WITH THIS
OPERATION.
(1) Disconnect the negative battery cable.
(2) Drain the cooling system. Refer to Group 7,
Cooling System for the procedure.
(3) Evacuate the refrigerant system.
(4) Remove the instrument panel. Refer to Group
8E, Instrument Panel and Systems for the procedure.
(5) Remove the refrigerant line retaining bolt from
the expansion valve (Fig. 1). Remove the refrigerant
lines from the expansion valve.
(6) Disconnect the electrical connector from the
bottom of the expansion valve (Fig. 1).
(7) Remove the expansion valve retaining bolts
and remove the valve from the vehicle.
(8) Remove the heater core coolant supply hoses
from the heater core (Fig. 2).(9) Working from inside the engine compartment,
remove the A/C-Heater housing retaining fasteners
from the bulkhead.
(10) Remove the A/C-Heater housing drain tube.
Remove the spring clip and pull the hose from the
housing nipple.
(11) Working from inside the vehicle, remove the
defroster duct from the A/C-Heater housing and body
attachment point.
(12) Remove the A/C-Heater housing retaining
bolts.
(13) Disconnect the electrical connectors from the
A/C-Heater housing.
(14) Remove the A/C-Heater housing from the
vehicle and place the assembly on a bench.
Fig. 1 Refrigerant Lines at Bulkhead
1 ± EXPANSION VALVE
2 ± REFRIGERANT LINE MANIFOLD RETAINING BOLT
3 ± BATTERY
4 ± LOW PRESSURE CUTOUT SWITCH ELECTRICAL
CONNECTOR
PLHEATING AND AIR CONDITIONING 24 - 1