2003 CHRYSLER CARAVAN engine overheat

SHIFT SCHEDULES
As mentioned earlier, the TCM has programming
that allows it to select a variety of shift schedules.
Shift schedule selection is dependent on the follow-
ing:
²Shift lever position
²Throttle position²Engine load
²Fluid temperature
²Software level
As driving conditions change, the TCM appropri-
ately adjusts the shift schedule. Refer to the follow-
ing chart to determine the appropriate operation
expected, depending on driving conditions.
Schedule Condition Expected Operation
Extreme ColdOil temperature at start-up below
-16É FPark, Reverse, Neutral and 2nd
gear only (prevents shifting which
may fail a clutch with frequent
shifts)
ColdOil temperature at start-up above
-12É F and below 36É F± Delayed 2-3 upshift
(approximately 22-31 mph)
± Delayed 3-4 upshift (45-53 mph)
± Early 4-3 costdown shift
(approximately 30 mph)
± Early 3-2 coastdown shift
(approximately 17 mph)
± High speed 4-2, 3-2, 2-1 kickdown
shifts are prevented
± No EMCC
WarmOil temperature at start-up above
36É F and below 80 degree F± Normal operation (upshift,
kickdowns, and coastdowns)
± No EMCC
HotOil temperature at start-up above
80É F± Normal operation (upshift,
kickdowns, and coastdowns)
± Full EMCC, no PEMCC except to
engage FEMCC (except at closed
throttle at speeds above 70-83 mph)
OverheatOil temperature above 240É F or
engine coolant temperature above
244É F± Delayed 2-3 upshift (25-32 mph)
± Delayed 3-4 upshift (41-48 mph)
± 3rd gear FEMCC from 30-48 mph
± 3rd gear PEMCC from 27-31 mph
Super OverheatOil temperature above 260É F ± All9Overheat9shift schedule
features apply
± 2nd gear PEMCC above 22 mph
± Above 22 mph the torque
converter will not unlock unless the
throttle is closed or if a wide open
throttle 2nd PEMCC to 1 kickdown
is made
8E - 22 ELECTRONIC CONTROL MODULESRS
TRANSMISSION CONTROL MODULE (Continued)
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the START position. If voltage reads above 0.2 volt,
correct poor starter to engine ground.
(a) Connect the positive voltmeter lead to the
battery positive terminal, and negative lead to bat-
tery cable terminal on starter solenoid. Rotate and
hold the ignition switch in the START position. If
voltage reads above 0.2 volt, correct poor contact at
battery cable to solenoid connection. If reading is
still above 0.2 volt after correcting poor contacts,
replace battery positive cable.
(b) If resistance tests do not detect feed circuit
failures, replace the starter motor.
DIAGNOSIS AND TESTING - FEED CIRCUIT
TEST
NOTE: The following results are based upon the
vehicle being at room temperature.
The following procedure will require a suitable
volt-ampere tester (Fig. 1).
CAUTION: Before performing any starter tests, the
ignition and fuel systems must be disabled.(1) Check battery before performing this test. Bat-
tery must be fully charged.
(2) Connect a volt-ampere tester to the battery ter-
minals. Refer to the operating instructions provided
with the tester being used.
(3) To disable the ignition and fuel systems, dis-
connect the Automatic Shutdown Relay (ASD). The
ASD relay is located in the Power Distribution Cen-
ter (PDC). Refer to the PDC cover for proper relay
location.
(4) Verify that all lights and accessories are OFF,
and the transmission shift selector is in the PARK
and SET parking brake.
CAUTION: Do not overheat the starter motor or
draw the battery voltage below 9.6 volts during
cranking operations.
(5) Rotate and hold the ignition switch in the
START position. Observe the volt-ampere tester (Fig.
1).
²If voltage reads above 9.6 volts, and amperage
draw reads above 280 amps, check for engine seizing
or faulty starter.
²If voltage reads 12.4 volts or greater and amper-
age reads 0 to 10 amps, check for corroded cables
and/or bad connections.
²Voltage below 9.6 volts and amperage draw
above 300 amps, the problem is the starter. Replace
the starter refer to starter removal.
(6) After the starting system problems have been
corrected, verify the battery state-of-charge and
charge battery if necessary. Disconnect all testing
equipment and connect ASD relay. Start the vehicle
several times to assure the problem has been cor-
rected.
SPECIFICATIONS
Torques
DESCRIPTION N´m Ft. Lbs. In. Lbs.
Starter Mounting Bolts 47.4 35
Starter Solenoid Battery
Nut11.3 8.3 100
Fig. 1 Volt Ampere Tester
RSSTARTING8F-33
STARTING (Continued)
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AIR CLEANER ELEMENT
REMOVAL
(1) Unsnap 2 clips.
(2) Lift cover and pull toward the engine and
remove cover tabs from air box.
(3) Lift cover and remove the element (Fig. 11).
INSTALLATION
(1) Install the air filter element into air box (Fig.
11).
(2) Move cover so that the tabs insert into the air
box.
(3) Push cover down and snap the 2 clips.
AIR CLEANER HOUSING
REMOVAL
(1) Disconnect the negative battery cable.
(2) Disconnect the inlet air temperature sensor
(Fig. 12).
(3) Remove the inlet hose to throttle body (Fig. 11).
(4) Remove the bolt for air box at upper radiator
cross member.
(5) Pull air box up and off over the single locating
pin.
(6) Remove air box from vehicle
INSTALLATION
(1) Install air box into vehicle and onto the locat-
ing pin.(2) Install bolt to hold air box to the upper radia-
tor cross member.
(3) Install the inlet hose to the throttle body.
(4) Connect the inlet air temperature sensor (Fig.
12).
(5) Connect the negative battery cable.
CYLINDER HEAD
DESCRIPTION
The cross flow designed, aluminum cylinder head
contains dual over-head camshafts with four valves
per cylinder (Fig. 13). The valves are arranged in two
in-line banks. The intake valves face toward the
front of the vehicle. The exhaust valves face the dash
panel. The cylinder head incorporates powdered
metal valve guides and seats. The cylinder head is
sealed to the block using a multi-layer steel head
gasket and retaining bolts.
Integral oil galleries provide lubrication passages
to the hydraulic lash adjusters, camshafts, and valve
mechanisms.
DIAGNOSIS AND TESTINGÐCYLINDER HEAD
GASKET
A cylinder head gasket leak can be located between
adjacent cylinders or between a cylinder and the
adjacent water jacket.
Possible indications of the cylinder head gasket
leaking between adjacent cylinders are:
²Loss of engine power
²Engine misfiring
²Poor fuel economy
Possible indications of the cylinder head gasket
leaking between a cylinder and an adjacent water
jacket are:
²Engine overheating
²Loss of coolant
Fig. 11 AIR BOX COVER
Fig. 12 IAT SENSOR 2.4L
9 - 24 ENGINE 2.4LRS
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AIR CLEANER HOUSING
REMOVAL
(1) Disconnect the negative battery cable.
(2) Disconnect the inlet air temperature sensor
(Fig. 16).
(3) Remove the inlet hose to throttle body.
(4) Remove the bolt for air box at upper radiator
cross member.
(5) Pull air box up and off over the single locating
pin.
(6) Remove air box from vehicle
INSTALLATION
(1) Install air box into vehicle and onto the locat-
ing pin.
(2) Install bolt to hold air box to the upper radia-
tor cross member.
(3) Install the inlet hose to the throttle body.
(4) Connect the inlet air temperature sensor (Fig.
16).
(5) Connect the negative battery cable.
CYLINDER HEAD
DESCRIPTION
The aluminum cylinder heads (Fig. 17) are
designed to create high flow combustion chambers to
improve performance, while minimizing the change
to the burn rate in the chamber. The cylinder head
incorporates the combustion chamber. Two valves
per-cylinder are used with inserted valve seats and
guides. A multi-layer steel (MLS) type gasket is used
between the cylinder head and engine block.
DIAGNOSIS AND TESTINGÐCYLINDER HEAD
GASKET
A cylinder head gasket leak can be located between
adjacent cylinders or between a cylinder and the
adjacent water jacket.
Possible indications of the cylinder head gasket
leaking between adjacent cylinders are:
²Loss of engine power
²Engine misfiring
²Poor fuel economy
Possible indications of the cylinder head gasket
leaking between a cylinder and an adjacent water
jacket are:
²Engine overheating
²Loss of coolant
²Excessive steam (white smoke) emitting from
exhaust
²Coolant foaming
CYLINDER-TO-CYLINDER LEAKAGE TEST
To determine if an engine cylinder head gasket is
leaking between adjacent cylinders, follow the proce-
dures in Cylinder Compression Pressure Test (Refer
to 9 - ENGINE - DIAGNOSIS AND TESTING). An
engine cylinder head gasket leaking between adja-
cent cylinders will result in approximately a 50±70%
reduction in compression pressure.
CYLINDER-TO-WATER JACKET LEAKAGE TEST
WARNING: USE EXTREME CAUTION WHEN THE
ENGINE IS OPERATING WITH COOLANT PRES-
SURE CAP REMOVED.
VISUAL TEST METHOD
With the engine cool, remove the coolant pressure
cap. Start the engine and allow it to warm up until
thermostat opens.
If a large combustion/compression pressure leak
exists, bubbles will be visible in the coolant.
COOLING SYSTEM TESTER METHOD
WARNING: WITH COOLING SYSTEM TESTER IN
PLACE, PRESSURE WILL BUILD UP FAST. EXCES-
SIVE PRESSURE BUILT UP, BY CONTINUOUS
ENGINE OPERATION, MUST BE RELEASED TO A
SAFE PRESSURE POINT. NEVER PERMIT PRES-
SURE TO EXCEED 138 kPa (20 psi).
Install Cooling System Tester 7700 or equivalent to
pressure cap neck. Start the engine and observe the
tester's pressure gauge. If gauge pulsates with every
power stroke of a cylinder a combustion pressure
leak is evident.
Fig. 16 Inlet Air Temperature Sensor
RSENGINE 3.3/3.8L9-99
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(11) Remove power steering fluid return hose with
cooler from vehicle.
INSTALLATION
INSTALLATION - 2.4L ENGINE
(1) Remove any used O-rings from ends of power
steering hose.
(2) Using a lint free towel, wipe clean hose ends,
power steering pump fitting and steering gear port.
(3) Install new O-ring on power steering gear end
of return hose. Lubricate O-ring using clean power
steering fluid.
CAUTION: Use care not to bend tube ends of the
power steering hoses when installing. Leaks and
restrictions may occur.
CAUTION: If a new return hose is being installed
and it does not have an insulating heat sleeve
installed, the heat shield from the original hose
must be transferred before hose installation.
(4) Route hose along rear of cradle crossmember
and start gear end of hose into gear port. Do not
tighten hose tube nut at this time.
(5) Attach hose to suspension cradle crossmember
using two routing clamps and bolts (Fig. 19). Tighten
clamp bolts to 23 N´m (200 in. lbs.) torque.
(6) Tighten return hose tube nut at power steering
gear port to 31 N´m (275 in. lbs.) torque.(7) Install the power steering fluid cooler on the
cradle crossmember reinforcement (Fig. 23). Install
the mounting bolts and tighten to 11 N´m (100 in.
lbs.).
CAUTION: Power steering fluid hoses must remain
away from the exhaust system and must not come
in contact with any unfriendly surfaces on the vehi-
cle.
(8) Route pump end of hose over cradle crossmem-
ber toward pump avoiding tight bends or kinking.
(9) Install return hose onto power steering pump
return fitting and secure with hose clamp (Fig. 19).
Tighten the screw-type clamp to a torque of 2 N´m
(18 in. lbs.).
CAUTION: To prevent overheating of power steering
fluid return hose, protective heat shield sleeve must
cover entire rubber hose.
(10) Slide insulating heat shield up over the clamp
on the return hose and tie-strap it in place.
(11) Install front emissions vapor canister. (Refer
to 25 - EMISSIONS CONTROL/EVAPORATIVE
EMISSIONS/VAPOR CANISTER - INSTALLATION)
(12) Lower vehicle.
(13) Fill and bleed the power steering system
using the Power Steering Pump Initial Operation
Procedure. (Refer to 19 - STEERING/PUMP - STAN-
DARD PROCEDURE)
(14) Inspect system for leaks.
INSTALLATION - 3.3L/3.8L ENGINE
(1) Remove any used O-rings from ends of power
steering hose.
(2) Using a lint free towel, wipe clean hose ends
and power steering gear hose port.
(3) Install a new O-ring on gear port end of power
steering fluid hose. Lubricate O-ring using clean
power steering fluid.
CAUTION: Use care not to bend tube ends of the
power steering hoses when installing. Leaks and
restrictions may occur.
CAUTION: Power steering fluid hoses must remain
away from the exhaust system and must not come
in contact with any unfriendly surfaces on the vehi-
cle.
(4) Route hose (with cooler attached) up toward
reservoir avoiding tight bends or kinking.
(5) Start steering gear end of hose into gear port.
Do not tighten hose tube nut at this time.
Fig. 23 POWER STEERING COOLER
1 - CRADLE CROSSMEMBER REINFORCEMENT
2 - POWER STEERING COOLER
RSPUMP19-49
HOSE - POWER STEERING RETURN (Continued)
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(3) Select sensors.
(4) Read the transmission temperature value.
(5) Compare the fluid temperature value with the
fluid temperature chart (Fig. 210).
(6) Adjust transmission fluid level shown on the
indicator according to the chart.
(7) Check transmission for leaks.
Low fluid level can cause a variety of conditions
because it allows the pump to take in air along with
the fluid. As in any hydraulic system, air bubbles
make the fluid spongy, therefore, pressures will be
low and build up slowly.
Improper filling can also raise the fluid level too
high. When the transaxle has too much fluid, the
gears churn up foam and cause the same conditions
which occur with a low fluid level.
In either case, air bubbles can cause overheating
and/or fluid oxidation, and varnishing. This can
interfere with normal valve, clutch, and accumulator
operation. Foaming can also result in fluid escaping
from the transaxle vent where it may be mistaken
for a leak.FLUID CONDITION
Along with fluid level, it is important to check the
condition of the fluid. When the fluid smells burned,
and is contaminated with metal or friction material
particles, a complete transaxle recondition is proba-
bly required. Be sure to examine the fluid on the dip-
stick closely. If there is any doubt about its condition,
drain out a sample for a double check.
MopartATF+4 (Automatic Transmission Fluid)
when new is red in color. The ATF is dyed red so it
can be identified from other fluids used in the vehicle
such as engine oil or antifreeze. The red color is not
permanent and is not an indicator of fluid condition.
As the vehicle is driven, the ATF will begin to look
darker in color and may eventually become brown.
This is normal.ATF+4 also has a unique odor that
may change with age. Consequently,odor and color
cannot be used to indicate the fluid condition
or the need for a fluid change.
After the fluid has been checked, seat the dipstick
fully to seal out water and dirt.
Fig. 210 Transmission Fluid Temperature Chart
1 - MAX. LEVEL
2 - MIN. LEVEL
21 - 202 41TE AUTOMATIC TRANSAXLERS
FLUID (Continued)
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Since there are four switches, there are 16 possible
combinations of open and closed switches (codes).
Seven of these codes are related to gear position and
three are recognized as ªbetween gearº codes. This
results in six codes which should never occur. These
are called ªinvalidº codes. An invalid code will result
in a DTC, and the PCM/TCM will then determine the
shift lever position based on pressure switch data.
This allows reasonably normal transmission opera-
tion with a TRS failure.
TRS SWITCH STATES
SLP T42 T41 T3 T1
PCL CL CL OP
RCL OP OP OP
NCL CL OP CL
ODOP OP OP CL
3OP OP CL OP
LCL OP CL CL
TRANSMISSION TEMPERATURE SENSOR
The TRS has an integrated thermistor (Fig. 329)
that the PCM/TCM uses to monitor the transmis-
sion's sump temperature. Since fluid temperature
can affect transmission shift quality and convertor
lock up, the PCM/TCM requires this information to
determine which shift schedule to operate in. The
PCM also monitors this temperature data so it can
energize the vehicle cooling fan(s) when a transmis-
sion ªoverheatº condition exists. If the thermistor cir-
cuit fails, the PCM/TCM will revert to calculated oil
temperature usage.
CALCULATED TEMPERATURE
A failure in the temperature sensor or circuit will
result in calculated temperature being substituted for
actual temperature. Calculated temperature is a pre-
dicted fluid temperature which is calculated from a
combination of inputs:
²Battery (ambient) temperature
²Engine coolant temperature
²In-gear run time since start-up
REMOVAL
(1) Remove valve body assembly from transaxle.
(Refer to 21 - TRANSMISSION/TRANSAXLE/AUTO-
MATIC - 41TE/VALVE BODY - REMOVAL)
(2) Remove transmission range sensor retaining
screw and remove sensor from valve body (Fig. 330).
(3) Remove TRS from manual shaft.
INSTALLATION
(1) Install transmission range sensor (TRS) to the
valve body and torque retaining screw (Fig. 330) to 5
N´m (45 in. lbs.).
(2) Install valve body to transaxle. (Refer to 21 -
TRANSMISSION/TRANSAXLE/AUTOMATIC -
41TE/VALVE BODY - INSTALLATION)
TRD LINK
DESCRIPTION
The Torque Reduction Link (TRD) is a wire
between the PCM and TCM that is used by the TCM
to request torque management. Torque management
controls or reduces torque output of the engine dur-
ing certain shift sequences, reducing torque applied
to the transaxle clutches.
OPERATION
The torque management signal is basically a
12-volt pull-up supplied by the PCM to the TCM over
the torque reduction link (TRD). Torque management
is requested when the TCM pulses this signal to
ground. The PCM recognizes this request and
responds by retarding ignition timing, killing fuel
injectors, etc. The PCM sends a confirmation of the
request to the TCM via the communication bus.
Torque reduction is not noticable by the driver, and
usually lasts for a very short period of time.
If the confirmation signal is not received by the
TCM after two sequential request messages, a diag-
nostic trouble code will be set.
Fig. 330 Remove Transmission Range Sensor
1 - TRANSMISSION RANGE SENSOR
2 - MANUAL VALVE CONTROL PIN
3 - RETAINING SCREW
RS41TE AUTOMATIC TRANSAXLE21 - 249
TRANSMISSION RANGE SENSOR (Continued)
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INSTALLATION
(1) Remove the tape or plugs from the evaporator
tube fittings and both expansion valve ports.
(2) Lubricate new rubber O-ring seals with clean
refrigerant oil and install them on the evaporator
tube fittings.
(3) Position the expansion valve onto the evapora-
tor tubes.
(4) Install and tighten the two screws that secure
the expansion valve to the evaporator tube sealing
plate. Tighten the screws to 11 N´m (97 in. lbs.).
(5) Reinstall the rear evaporator line extension
onto the expansion valve. (Refer to 24 - HEATING &
AIR CONDITIONING/PLUMBING - REAR/EVAPO-
RATOR - INSTALLATION - EVAPORATOR LINE
EXTENSION).
(6) Install the foam insulator wrap over the rear
expansion valve.
(7) Reinstall the rear heater-A/C unit housing into
the vehicle. (Refer to 24 - HEATING & AIR CONDI-
TIONING/DISTRIBUTION - REAR/REAR HEATER-
A/C HOUSING - INSTALLATION).
(8) Run the HVAC Cooldown Test to verify proper
operation.
HEATER CORE
DESCRIPTION
The rear heater core is located near the front of
the rear heater-A/C unit housing, behind the right
rear wheel house. It is a heat exchanger made of
rows of tubes and fins. One end of the core is fitted
with a molded plastic tank that includes integral
heater core inlet and outlet nipples. The heater core
can be serviced without removing the rear heater-A/C
unit housing from the vehicle. The heater core cannot
be repaired and, if faulty or damaged, it must be
replaced.
OPERATION
Engine coolant is circulated through heater hoses
to the heater core at all times. As the coolant flows
through 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 air door
allows control of the heater output air temperature
by controlling how much of the air flowing through
the rear heater-A/C unit housing is directed through
the heater core.
STANDARD PROCEDURE - HEATER CORE
FILLING
In its final installed position, the rear heater core
is positioned higher than the radiator fill cap. There-fore, when the cooling system is drained and refilled,
gravity will not refill the heater core with coolant to
the proper level. This may result in two problems:1.
Insufficient coolant level in the engine cooling sys-
tem, which may result in engine overheating.2.Air
entrapped within the rear heater core, which may
result in insufficient rear heater performance. There
are two methods that may be employed to prevent
these problems:1.Pre-filling of the rear heater core.
2.Thermal cycling of the engine cooling system. Fol-
lowing are descriptions of both prevention methods,
as well as a method to verify rear heater perfor-
mance.
WARNING: REFER TO THE APPLICABLE WARN-
INGS AND CAUTIONS FOR THIS SYSTEM BEFORE
PERFORMING THE FOLLOWING OPERATION.
(Refer to 24 - HEATING & AIR CONDITIONING/
PLUMBING FRONT - WARNING - HEATER PLUMB-
ING).
PRE-FILLING
If the rear heater core or the rear heater-A/C hous-
ing have been removed from the vehicle for service,
the rear heater core may be pre-filled with the proper
engine coolant mixture prior to reconnecting the
heater hoses to the heater core hose fittings.
(1) The heater core should be installed in the rear
heater-A/C unit housing, and the rear heater-A/C
unit housing should be installed in the vehicle.
(2) Take the proper precautions to protect the car-
peting below the rear heater core from spilled engine
coolant and have absorbent toweling readily avail-
able to mop up any spills.
(3) Insert the small end of an appropriate funnel
into the upper hose fitting of the heater core (Fig. 4).
Fig. 4 Pre-Filling Heater Core - Typical
1 - REAR HEATER CORE
24 - 98 PLUMBING - REARRS
EXPANSION VALVE (Continued)
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