air condition DODGE NEON 2000 Service Owner's Manual

CONDITION POSSIBLE CAUSE CORRECTION
16. Electric cooling fan not
operating properly.16. Check electric fan operation and
repair as necessary.
17. Cylinder head gasket leaking. 17. Check cylinder head gasket for
leaks. Refer to testing cooling
system for leaks. For repairs, refer
to Group 9, Engine.
18. Heater core leaking. 18. Check heater core for leaks.
Refer to Group 24, Heating and Air
Conditioning and repair as
necessary.
TEMPERATURE GAUGE READING
IS INCONSISTENT (FLUCTUATES,
CYCLES OR IS ERRATIC)1. The gauge may cycle up and
down. This is due to the cycling of
the electric radiator fan.1. A normal condition. No correction
is necessary. If gauge cycling is
going into the hot zone, check
electric fan operation and repair as
necessary. Refer to procedure in
this section.
2. During cold weather operation
with the heater blower in the high
position, the gauge reading may
drop slightly.2. A normal condition. No correction
is necessary.
3, Temperature gauge or engine
mounted gauge sensor is defective
or shorted.3. Check operation of gauge and
repair as necessary. Refer to Group
8E, Instrument Panel and Gauges.
4. Gauge reading rises when
vehicle is brought to a stop after
heavy use (engine still running).4. A normal condition. No correction
is necessary. The gauge should
return to normal range after vehicle
is driven.
5. Gauge reading high after
restarting a warmed-up (hot)
engine.5. A normal condition. No correction
is necessary. The gauge should
return to normal range after a few
minutes of engine operation.
6. Coolant level low in radiator (air
will build up in the cooling system
causing the thermostat to open
late).6. Check and correct coolant leaks.
Refer to Testing Cooling System For
Leaks in the section.
7. Cylinder head gasket leaking
allowing exhaust gas to enter
cooling system. This will cause
thermostat to open late.7. (a) Check for cylinder head
gasket leaks with a commercially
available Block Leak Tester. Repair
as necessary.
(b) Check for coolant in the engine
oil. Inspect for white steam emitting
from exhaust system. Repair as
necessary.
8. Water pump impeller loose on
shaft.8. Check water pump and replace
as necessary. Refer to Water Pump
in this section.
9. Loose drive belt (water pump
slipping).9. Check drive belt and correct as
necessary.
PLCOOLING SYSTEM 7 - 9
DIAGNOSIS AND TESTING (Continued)

CONDITION POSSIBLE CAUSE CORRECTION
10. Air leak on the suction side of
water pump allows air to build up in
cooling system. This will cause the
thermostat to open late.10. Locate leak and repair as
necessary.
PRESSURE CAP IS BLOWING
OFF STEAM AND/OR COOLANT
FLOWING INTO RECOVERY
CONTAINER. TEMPERATURE
GAUGE READING MAY BE ABOVE
NORMAL, BUT NOT HIGH.
COOLANT LEVEL MAY BE HIGH
IN RECOVERY CONTAINER.1. Pressure relief valve in radiator
cap is defective.1. Check condition of radiator cap
and seals. Refer to Radiator Cap in
this section. Replace as necessary.
COOLANT LOSS TO THE
GROUND WITHOUT PRESSURE
CAP BLOWOFF. GAUGE IS
READING HIGH OR HOT.1. Coolant leaks in radiator, cooling
system hoses, water pump or
engine.1. Pressure test and repair as
necessary. Refer to Testing Cooling
System For Leaks in this section.
DETONATION OR PRE-IGNITION
(NOT CAUSED BY IGNITION
SYSTEM). GAUGE MAY OR MAY
NOT BE READING HIGH.1. Engine overheating. 1. Check reason for overheating
and repair as necessary.
2. Freeze point of coolant not
correct.2. Check the freeze point of the
coolant. Refer to Coolant
Concentration Testing in this
section. Adjust glycol-to-water ratio
as required.
HOSE OR HOSES COLLAPSE
WHEN ENGINE IS COOLING1. Vacuum created in cooling
system on engine cool-down is not
being relieved through coolant
recovery/reserve container system.1. (a) Radiator cap relief valve
stuck. Refer to Radiator Cap in this
section. Replace as necessary.
(b) Hose between coolant
recovery/reserve container and
radiator is kinked. Repair as
necessary.
(c) Vent at coolant recovery/reserve
container is plugged. Clean vent
and repair as necessary.
(d) Recovery/reserve container is
internally blocked or plugged. Check
for blockage and repair as
necessary.
ELECTRIC RADIATOR FAN
OPERATES ALL THE TIME.1. Fan relay, powertrain control
module (PCM) or engine coolant
temperature sensor defective.1. Refer to appropriate Powertrain
Diagnostic Procedures manual for
operation of the DRB scan tool.
Repair as necessary.
2. Check for low coolant level. 2. Repair as necessary.
7 - 10 COOLING SYSTEMPL
DIAGNOSIS AND TESTING (Continued)

CONDITION POSSIBLE CAUSE CORRECTION
ELECTRIC RADIATOR FAN WILL
NOT OPERATE. GAUGE READING
HIGH OR HOT1. Fan motor defective. 1. Refer to appropriate Powertrain
Diagnostic Procedures manual for
operation of the DRB scan tool.
Repair as necessary.
2. Fan relay, powertrain control
module (PCM) or engine coolant
temperature sensor defective.2. Refer to appropriate Powertrain
Diagnostic Procedures manual for
operation of the DRB scan tool.
Repair as necessary.
3. Blown fuse in power distribution
center (PDC).3. Determine reason for blown fuse
and repair as necessary.
NOISY FAN 1. Fan blade loose. 1. Replace fan blade assembly.
Refer to Cooling System Fan in this
section.
2. Fan blade striking a surrounding
object.2. Locate point of fan blade contact
and repair as necessary.
3. Air obstructions at radiator or A/C
condenser.3. Remove obstructions and/or
clean debris from radiator and/or
A/C condenser.
4. Electric fan motor defective. 4. Refer to procedure in this section.
INADEQUATE AIR CONDITIONER
PERFORMANCE (COOLING
SYSTEM SUSPECTED)1. Radiator and/or air conditioning
condenser is restricted, obstructed
or dirty.1. Remove restriction and/or clean
as necessary.
2. Electric radiator fan not operating
when A/C is on.2. Refer to appropriate Powertrain
Diagnostic Procedures manual for
operation of the DRB scan tool.
Repair as necessary.
3. Engine is overheating (heat may
be transferred from radiator to A/C
condenser). High underhood
temperature due to engine
overheating may also transfer heat
to A/C components.3. Correct overheating condition.
Refer to this section.
PLCOOLING SYSTEM 7 - 11
DIAGNOSIS AND TESTING (Continued)

CONDITION POSSIBLE CAUSE CORRECTION
INADEQUATE HEATER
PERFORMANCE.1. Has a diagnostic trouble code
(DTC) been set?1. Refer to On-Board Diagnostic in
Group 25, Emission Control
Systems.
2. Coolant level low. 2. Refer to testing cooling system
for leaks in this section. Repair as
necessary.
3. Obstructions in heater hose
fittings at engine.3. Remove heater hoses at both
ends and check for obstructions.
Repair as necessary.
4. Heater hose kinked. 4. Locate kinked area and repair as
necessary.
5. Water pump is not pumping
coolant to heater core. When the
engine is fully warmed up, both
heater hoses should be hot to the
touch. The water pump drive belt
may be slipping causing poor water
pump operation.5. Refer to water pump in this
section. Repair as necessary.
HEAT ODOR 1. Various heat shields are used at
certain driveline components. One
or more of these shields may be
missing.1. Locate missing shields and
replace or repair as necessary.
2. Is temperature gauge reading
above the normal range?2. Refer to the previous
Temperature Gauge Reads High in
these Diagnostic Charts. Repair as
necessary.
3. Is cooling fan operating
correctly?3. Refer to Cooling System Fan in
this section for diagnosis. Repair as
necessary.
4. Has undercoating been applied
to any unnecessary component.4. Clean undercoating as necessary.
5. Engine may be running rich
causing the catalytic converter to
overheat.5. Refer to appropriate Powertrain
Diagnostic Procedures manual for
operation of the DRB scan tool.
Repair as necessary.
POOR DRIVEABILITY
(THERMOSTAT POSSIBLY STUCK
OPEN). GAUGE MAY BE READING
LOW1. For proper driveability, good
vehicle emissions and for
preventing build-up of engine oil
sludge, the thermostat must be
operating properly. Has a diagnostic
trouble code (DTC ) been set?1. Refer to On-Board Diagnostics in
Group 25, Emission Control
Systems. DTC's may also be check
using the DRB scan tool. Refer to
the proper Powertrain Diagnostic
Procedure manual for checking the
thermostat if necessary.
7 - 12 COOLING SYSTEMPL
DIAGNOSIS AND TESTING (Continued)

CONDITION POSSIBLE CAUSE CORRECTION
STEAM IS COMING FROM FRONT
OF VEHICLE NEAR GRILL AREA
WHEN WEATHER IS WET,
ENGINE IS WARMED UP,
RUNNING, AND VEHICLE IS
STATIONARY. TEMPERATURE
GAUGE IS IN NORMAL RANGE.1. During wet weather, moisture
(snow, ice or rain condensation) on
the radiator will evaporate when the
thermostat opens. This opening
allows heated water into the
radiator. When the moisture contact
the hot radiator, steam may be
emitted. This usually occurs in cold
weather with no fan or airflow to
blow it away.1. Occasional steam emitting from
this area is normal. No repair is
necessary.
COOLANT COLOR 1. Coolant color is not necessarily
an indication of adequate corrosion
or temperature protection. Do not
rely on coolant color for determining
condition of coolant.1. Check the freeze point of the
coolant. Refer to Coolant
Concentration Testing in this section
for procedure. Adjust the glycol-to-
water ratio as required.
COOLANT LEVEL CHANGES IN
COOLANT RECOVERY/RESERVE
CONTAINER1. Level changes are to be
expected as coolant volume
fluctuates with engine temperature.
If the level in the container was
between the FULL and ADD marks
at normal engine operating
temperature, the level should return
to within that range after operation
at elevated temperatures.1. A normal condition. No repair is
necessary.
PLCOOLING SYSTEM 7 - 13
DIAGNOSIS AND TESTING (Continued)

ENGINE THERMOSTAT TESTING
The thermostat is operated by a wax filled con-
tainer (pellet) which is sealed. When heated coolant
reaches a predetermined temperature the wax pellet
expands enough to overcome the closing spring and
water pump pressure, which forces the valve to open.
Coolant leakage into the pellet will cause a thermo-
stat to fail open. Do not attempt to free up a thermo-
stat with a screwdriver.
The thermostat that opens too soon type failure
mode is included in the on-board diagnosis. Thecheck engine light will not be lit by an open too soon
condition. If it has failed open, a diagnostic trouble
code (DTC) will be set. Do not change a thermostat
for lack of heater performance or temperature gauge
position, unless a DTC is present. See Diagnosis for
other probable causes. Thermostat failing shut is the
normal long term mode of failure, and normally, only
on high mileage vehicles. The temperature gauge will
indicate this. Refer to Diagnosis in this section.
ACCESSORY DRIVE BELT DIAGNOSIS
CONDITION POSSIBLE CAUSE CORRECTION
BELT SLIPPAGE 1. Belt slipping because of
insufficient tension.1. Retension generator belt.
Replace the power steering belt's
automatic belt tensioner.
2. Belt excessively glazed or
hardened from heat and excessive
slippage.2. Replace belt.
3. Incorrect belt. 3. Replace belt.
4. Driven component bearing
failure.4. Replace faulty component.
5. Belt or pulley subjected to
substance (belt dressing, oil,
ethylene glycol) that has reduced
friction.5. Replace belt and clean pulleys.
BELT NOISE (OBJECTIONABLE
SQUEAL, SQUEAK, OR RUMBLE)1. Belt slippage. 1. Retension generator belt, replace
belt, or automatic belt tensioner.
2. Foreign material imbedded in
belt.2. Replace belt.
3. Non-uniform belt. 3. Replace belt.
4. Misaligned pulley(s). 4. Align accessories.
5. Non-uniform groove or eccentric
pulley.5. Replace pulley(s).
6. Bearing noise. 6. Locate and repair.
BELT ROLLED OVER IN GROOVE
OR BELT JUMPS OFF1. Broken cord in belt. 1. Replace belt.
2. Belt tension too loose, or too
tight.2. Retension generator belt.
Replace the power steering belt's
automatic belt tensioner.
3. Misaligned pulleys. 3. Align accessories.
4. Non-uniform grooves or eccentric
pulley.4. Replace pulley(s).
5. Foreign object(s) in grooves. 5. Remove foreign objects in
groove.
7 - 14 COOLING SYSTEMPL
DIAGNOSIS AND TESTING (Continued)

(3) Remove thermostat/engine outlet connector
bolts (Fig. 22).
(4) Remove thermostat and O-ring assembly.
INSTALLATION
(1) Clean all sealing surfaces.
(2) Place the new thermostat assembly into the
thermostat housing/outlet connector. Align vent with
notch in cylinder head.
(3) Install thermostat housing/outlet connector
onto cylinder head and tighten bolts to 12.5 N´m (110
in. lbs.).
(4) Install upper radiator hose.
(5) Connect the coolant recovery/reserve system
hose.
(6) Refill cooling system. Refer to procedure in this
section.
RADIATOR
REMOVAL
WARNING: DO NOT REMOVE THE CYLINDER
BLOCK PLUG OR THE RADIATOR DRAINCOCK
WITH THE SYSTEM HOT AND UNDER PRESSURE
BECAUSE SERIOUS BURNS FROM COOLANT CAN
OCCUR.
(1) Disconnect negative cable from battery.
(2) Drain cooling system. Refer to procedure in
this section.
(3) Remove upper radiator hose from the radiator.
(4) Disconnect and cap automatic transmission
hoses, if equipped.(5) Disconnect cooling fan motor electrical connec-
tor.
(6) Remove cooling fan module retaining screws,
located on the top of the shroud (Fig. 23). Lift shroud
up and out of bottom shroud attachment clips sepa-
rating shroud from radiator.
(7) Remove the lower radiator hose.
(8) Remove upper radiator isolator bracket mount-
ing screws (Fig. 24). Disconnect the engine block
heater wire, if equipped.
(9) Remove the air conditioning condenser attach-
ing screws located at the front of the radiator, if
equipped (Fig. 25), then lean condenser forward.
NOTE: It is not necessary to discharge the air con-
ditioning system to remove the radiator.
Fig. 22 Thermostat/Engine Outlet Connector
1 ± PRESSURE CAP
2 ± THERMOSTAT HOUSING/ENGINE OUTLET CONNECTOR
3 ± THERMOSTAT
4 ± O-RING
5 ± VENT FACING UP
Fig. 23 Fan Module Mounting
1 ± SCREWS
2 ± LOWER MOUNTS
3 ± FAN MOTOR ELECTRICAL CONNECTOR
Fig. 24 Radiator Mounting
1 ± UPPER RADIATOR HOSE
2 ± UPPER RADIATOR MOUNTS
PLCOOLING SYSTEM 7 - 21
REMOVAL AND INSTALLATION (Continued)

(10) Radiator can now be lifted free from engine
compartment.Care should be taken not to dam-
age radiator cooling fins or water tubes during
removal.
INSTALLATION
(1) Slide radiator down into position behind radia-
tor support (yoke).
(2) Attach air conditioning condenser to radiator, if
equipped (Fig. 25), with four mounting screws.
Tighten screws to 5.4 N´m (50 in. lbs.). Then seat the
radiator assembly lower rubber isolators into the
mounting holes provided in the lower crossmember.
(3) Install and tighten radiator isolator mounting
bracket screws to 10 N´m (90 in. lbs.) (Fig. 24). The
radiator should have clearance to move up, approxi-
mately 5±8 mm (0.20±0.31 in.) after assembled.
(4) Install lower radiator hose. Align the hose and
position the clamp so it will not interfere with engine
components.
(5) Connect automatic transmission hoses, if
equipped. Tighten hose clamps to 2 N´m (18 in. lbs.).
(6) Slide fan module down into clip(s) on lower
radiator flange (Fig. 23). Install retaining screws and
tighten to 7.5 N´m (65 in. lbs.).
(7) Connect the cooling fan motor electrical connec-
tor.
(8) Install upper radiator hose. Align the hose and
position the clamp so they will not interfere with the
engine or the hood.
(9) Connect negative cable to battery.
(10) Fill cooling system with coolant. Refer to pro-
cedure in this section.
(11) Operate engine until it reaches normal operat-
ing temperature. Check cooling system and auto-
matic transmission for correct fluid levels.
RADIATOR DRAINCOCK
REMOVAL
(1) Turn the drain cock stem counterclockwise to
unscrew the stem. When the stem is unscrewed to
the end of the threads, pull the stem (Fig. 26) from
the radiator tank.
INSTALLATION
(1) Push the draincock assembly body into the
tank opening.
(2) Tighten the draincock stem by turning clock-
wise to 2.0-2.7 N´m (18-25 in. lbs.).
COOLING FAN MODULE
All models use a single speed electric motor driven
cooling system fan. The fan module includes a motor,
fan blade, and support shroud. The module is fas-
tened to the radiator by screws.
REMOVAL
WARNING: DO NOT REMOVE THE CYLINDER
BLOCK PLUG OR THE RADIATOR DRAINCOCK
WITH THE SYSTEM HOT AND UNDER PRESSURE
BECAUSE SERIOUS BURNS FROM COOLANT CAN
OCCUR.
(1) Disconnect negative cable from battery.
(2) Drain cooling system below upper radiator hose
level. Refer to procedure in this section.
(3) Remove upper radiator hose from radiator (Fig.
27).
(4) Disconnect fan module electrical connector.
(5) Remove fan module screws from radiator (Fig.
28).
(6) Lift fan shroud up and out of lower shroud
attachment clips.
(7) Refer to Disassembly and Assembly in this sec-
tion for fan module sub-component service proce-
dures.
Fig. 25 A/C Condenser to Radiator Mounting Screws
1 ± AIR CONDITIONING CONDENSER TO RADIATOR
MOUNTING SCREWS
2 ± LOWER ISOLATOR MOUNTS
Fig. 26 Draincock
1 ± DRAIN COCK BODY
2 ± DRAIN COCK HOUSING
7 - 22 COOLING SYSTEMPL
REMOVAL AND INSTALLATION (Continued)

(2) Connect recovery hose to water outlet connec-
tor/thermostat housing (Fig. 29).
(3) Fill container to proper level. Refer to Cooling
System Refilling in this section.
ENGINE BLOCK HEATER
REMOVAL
(1) Drain coolant from radiator and cylinder block.
Refer to Cooling System Draining in this section for
procedure.
(2) Detach power cord plug from heater (Fig. 31).
(3) Loosen screw in center of heater. Remove
heater assembly (Fig. 31).
INSTALLATION
(1) Thoroughly clean core hole and heater seat.
(2) Insert heater assembly with element loop posi-
tionedupward (Fig. 31).
(3) With heater seated, tighten center screw
securely to assure a positive seal.
(4) Connect power cord to block heater (Fig. 31).
(5) Fill cooling system with coolant to the proper
level, vent air, and inspect for leaks.
ACCESSORY DRIVE BELTS
POWER STEERING PUMP AND AIR CONDITIONING
COMPRESSOR BELT
REMOVAL
(1) Using a 17 mm wrench, rotate belt tensioner
clockwise (Fig. 33) until belt can be removed from
power steering pump pulley. Gently, release spring
tension on tensioner.
(2) Remove belt (Fig. 34).
INSTALLATION
(1) Install belt (Fig. 34) over all pulleys except for
the power steering pump pulley.
(2) Using a 17 mm wrench, rotate belt tensioner
clockwise (Fig. 33) until belt can be installed onto
power steering pulley. Release spring tension onto
belt.
NOTE: When installing drive belt onto pulleys,
make sure that belt is properly routed and all
V-grooves make proper contact with pulley grooves.
(3) After belt is installed, inspect belt length indi-
cator marks (Fig. 35). The indicator mark should be
within the minimum belt length and maximum belt
length marks. On a new belt, the indicator mark
should align approximately with the nominal belt
length mark.
Fig. 31 Engine Block Heater
1 ± CORE PLUG
2 ± BLOCK HEATER
3 ± POWER CORD
Fig. 32 Accessory Drive Belts
1 ± GENERATOR BELT
2 ± AUTOMATIC BELT TENSIONER
3 ± POWER STEERING PUMP/A/C COMPRESSOR BELT
7 - 24 COOLING SYSTEMPL
REMOVAL AND INSTALLATION (Continued)

GENERATOR BELT
REMOVAL
(1) Remove power steering pump/air conditioning
compressor drive belt.
(2) Loosen pivot bolt, then locking nut and adjust-
ing bolt (Fig. 36).
(3) Remove generator belt.
NOTE: When installing drive belt onto pulleys,
make sure that belt is properly routed and all
V-grooves make proper contact with pulley grooves.
INSTALLATION
(1) Install belt and/or adjust belt tension by tight-
ening adjusting bolt. Adjust belt to specification
shown in Belt Tension Chart.
NOTE: Due to space limitations, the use of a belt
tension gauge is limited. Therefore, measure the
belt deflection at the center span of the generator
belt. Refer to Belt Tension Chart for specifications.
(2) Tighten pivot bolt to 54 N´m (40 ft. lbs.) and
locking nut to 54 N´m (40 ft. lbs.) (Fig. 36).
Fig. 33 Accessory BeltÐRemoving
1 ± 17mm WRENCH
Fig. 34 Power Steering/Air Conditioning Belt
1 ± BELT
2 ± P/S PULLEY
3 ± TENSIONER PULLEY
4 ± CRANKSHAFT PULLEY
5 ± BELT6 ± P/S PULLEY
7 ± TENSIONER PULLEY
8 ± A/C PULLEY
9 ± CRANKSHAFT PULLEY
PLCOOLING SYSTEM 7 - 25
REMOVAL AND INSTALLATION (Continued)