2005 CHRYSLER CARAVAN transmission

gizes the heated seat elements. The heated seat mod-
ule will continue to cycle the N-FET as needed to
maintain the selected temperature set point.
DIAGNOSIS AND TESTING
HEATED SEAT MODULE
If a heated seat heats but one or both indicator
lamps on the heated seat switch fail to operate, test
the heated seat switch. (Refer to 8 - ELECTRICAL/
HEATED SEATS/DRIVER HEATED SEAT SWITCH
- DIAGNOSIS AND TESTING). If the heated seat
switch checks OK, proceed as follows.
(1) Check the heated seat element (Refer to 8 -
ELECTRICAL/HEATED SEATS/HEATED SEAT
ELEMENT - DIAGNOSIS AND TESTING).
(2) Check the heated seat sensor (Refer to 8 -
ELECTRICAL/HEATED SEATS/HEATED SEAT
SENSOR - DIAGNOSIS AND TESTING).
(3) Using a voltmeter, back probe the appropriate
heated seat module connector, do not disconnect.
Check for battery voltage at the appropriate pin cav-
ities. If OK go to Step 4. If not OK, repair the open
or shorted voltage supply circuit as required.
(4) Using a ohmmeter, back probe the appropriate
heated seat module connector, do not disconnect.
Check for proper continuity to ground on the ground
pin cavities. Continuity should be present. If OK
replace the heated seat module. If Not OK, repair the
open or shorted ground circuit as required.
REMOVAL
(1) Disconnect and isolate the negative battery
cable.
(2) Remove the appropriate front seat from the
vehicle (Refer to 23 - BODY/SEATS/SEAT -
REMOVAL).
(3) Unsnap the module from the seat cushion pan.
(4) Disconnect the module wire harness connec-
tors.
INSTALLATION
(1) Connect the module wire harness connectors.
(2) Snap the module on the seat cushion pan.
(3) Install the appropriate front seat in the vehicle
(Refer to 23 - BODY/SEATS/SEAT - INSTALLA-
TION).
(4) Connect and isolate the negative battery cable.
MEMORY SEAT/MIRROR
MODULE
DESCRIPTION
Vehicles equipped with the memory seat/mirror
option, utilize a memory module located under the
drivers front seat. This module is basically wired in-
line between the power seat switch and the power
seat track/adjuster motors, or in-line between the
power mirror switch and the power side view mir-
ror(s) motor(s). The Memory Seat/Mirror Module
(MSMM) contains a central processing unit that com-
municates with other modules on the Programmable
Communications Interface (PCI) data bus network.
The MSMM receives hard wired inputs from the
driver power seat switch and the potentiometers on
each of the driver side power seat track motors, or
from the power mirror switch and the potentiometers
on the side view mirror. The MSMM receives mes-
sages over the PCI data bus from the Body Control
Module (BCM) (memory switch status), the Power-
train Control Module (PCM) (vehicle speed status).
The MSMM will prevent the seat memory recall
function from being initiated if the driver side seat
belt is buckled, if the transmission gear selector lever
is not in the Park or Neutral positions, or if the vehi-
cle is moving.
For diagnosis of the MSMM or the PCI data bus, a
DRB IIItscan tool and the proper Diagnostic Proce-
dures Information are recommended. The MSMM
cannot be repaired and, if faulty or damaged, it must
be replaced.
OPERATION
When memory system operation is requested
(depressing of the memory switch), a resistor multi-
plexed signal is sent from the memory switch to the
Body Control Module (BCM). The BCM will then
send the appropriate signals out to the Memory Seat/
Mirror Module (MSMM), the MSMM then applies the
voltage supply to the power seat track or side-view
mirror if the proper requirements are met. The vehi-
cle speed must equal zero and the transmission must
be in park or neutral in order for the memory system
to function.
DIAGNOSIS AND TESTING
MEMORY SEAT/MIRROR MODULE
Any diagnosis of the Memory Seat/Mirror sys-
tem should begin with the use of the DRB IIIt
diagnostic tool. For information on the use of
the DRB IIIt, refer to the appropriate Diagnos-
tic Procedures information.
RSELECTRONIC CONTROL MODULES8E-9
HEATED SEAT MODULE (Continued)

Inspect the related wiring harness connectors for
broken, bent, pushed out, or corroded terminals.
Refer to the appropriate wiring information.
REMOVAL
(1) Disconnect and isolate the battery negative
cable.
(2) Remove the driver side front bucket seat
retaining nuts from under the vehicle (Refer to 23 -
BODY/SEATS/SEAT - REMOVAL).
(3) Lift the drivers seat up and out of the mount-
ing holes in the floor pan and lay the seat rearward
to access the module located under the seat.
(4) Disconnect the memory seat/mirror module
electrical connectors. Depress the retaining tab and
pull straight apart.
(5) Remove the module retaining bolts and remove
the module from the bracket.
INSTALLATION
(1) Position and install the module retaining bolts.
(2) Connect the memory seat/mirror module elec-
trical connectors.
(3) Position the drivers seat in the mounting holes
in the floor pan.
(4) Install the driver side front bucket seat retain-
ing nuts from under the vehicle (Refer to 23 - BODY/
SEATS/SEAT - INSTALLATION).
(5) Connect the battery negative cable.
POWER LIFTGATE CONTROL
MODULE
DESCRIPTION
Vehicles equipped with a power liftgate (PLG) uti-
lize a PLG control module. This module is located on
the vehicles left side D-pillar just below the motor
assembly (Fig. 7) and contains a microprocessor,
which is used to communicate to the vehicles body
control module. The PLG control module receives and
monitors logic inputs from all the PLG system
switches except for the outside handle switch. This
module also contains the software technology to
detect liftgate obstructions and stop and/or reverse
the door accordingly.
OPERATION
The power liftgate control module contains the
electronic circuitry and software used to control the
sequence of events for the power liftgate system. This
module communicates on the Programmable Commu-
nications Interface (PCI) bus circuit with the vehicles
Body Control Module (BCM) to monitor many differ-
ent inputs and outputs such as door lock status,
transmission gear selector position and vehicle speed.(Refer to 8 - ELECTRICAL/POWER DOORS - OPER-
ATION) for more information.
DIAGNOSIS AND TESTING
POWER LIFTGATE CONTROL MODULE
Any diagnosis of the Power Liftgate system
should begin with the use of the DRB IIItdiag-
nostic tool. For information on the use of the
DRB IIIt, refer to the appropriate Diagnostic
Procedures information.
Inspect the related wiring harness connectors for
broken, bent, pushed out, or corroded terminals.
Refer to the appropriate wiring information.
REMOVAL
(1) Disconnect and isolate the battery negative
cable.
(2) Remove the left D-pillar trim panel from the
vehicle. (Refer to 23 - BODY/INTERIOR/LEFT
D-PILLAR TRIM PANEL - REMOVAL)
(3) Disconnect the wire harness connections from
the power liftgate motor assembly.
(4) Remove the screw holding the power liftgate
control module to the D-pillar (Fig. 8).
(5) Remove the power liftgate control module from
the vehicle.
Fig. 7 POWER LIFTGATE CONTROL MODULE
1 - POWER LIFTGATE CONTROL MODULE
2 - RETAINING SCREWS
3 - D-PILLAR
4 - POWER LIFTGATE MOTOR
5 - ELECTRICAL CONNECTORS
8E - 10 ELECTRONIC CONTROL MODULESRS
MEMORY SEAT/MIRROR MODULE (Continued)

INSTALLATION
(1) Install the Power Liftgate (PLG) control mod-
ule on the D-pillar and install retaining screw.
(2) Connect the wire harness connections to the
PLG control module. Be certain to slide connector
locks to the locked position.
(3) Install the D-pillar trim panel on the vehicle.
(Refer to 23 - BODY/INTERIOR/LEFT D-PILLAR
TRIM PANEL - INSTALLATION)
(4) Connect the battery negative cable.
(5) Using an appropriate scan tool, check and
erase any PLG control module diagnostic trouble
codes.
(6) Verify PLG system operation. Cycle the PLG
through one complete open and close cycle, this will
allow the PLG control module to relearn its cycle
with the new components.
POWERTRAIN CONTROL
MODULE
DESCRIPTION
DESCRIPTION
The Powertrain Control Module (PCM) is a digital
computer containing a microprocessor (Fig. 9). ThePCM receives input signals from various switches
and sensors referred to as Powertrain Control Mod-
ule Inputs. Based on these inputs, the PCM adjusts
various engine and vehicle operations through
devices referred to as Powertrain Control Module
Outputs.
NOTE: PCM Inputs:
²Air Conditioning Pressure Transducer
²Ambient temperature Sensor
²ASD Relay
²Battery Temperature Sensor (NGC)
²Battery Voltage
²Brake Switch
²Camshaft Position Sensor
²Crankshaft Position Sensor
²Distance Sensor (from transmission control mod-
ule)
²EGR Position Feedback
²Engine Coolant Temperature Sensor
²Heated Oxygen Sensors
²Ignition sense
²Intake Air Temperature Sensor
²Knock Sensor
²Leak Detection Pump Feedback
²Manifold Absolute Pressure (MAP) Sensor
²Park/Neutral
²PCI Bus
²Power Steering Pressure Switch
²Proportional Purge Sense
Fig. 8 POWER LIFTGATE CONTROL MODULE
1 - POWER LIFTGATE CONTROL MODULE
2 - RETAINING SCREWS
3 - D-PILLAR
4 - POWER LIFTGATE MOTOR
5 - ELECTRICAL CONNECTORS
Fig. 9 Powertrain Control Module (PCM)
1 - Battery
2 - Power Distribution Center
3 - Powertrain Control Module
RSELECTRONIC CONTROL MODULES8E-11
POWER LIFTGATE CONTROL MODULE (Continued)

²SCI Receive
²Speed Control
²Throttle Position Sensor
²Transmission Control Relay (Switched B+)
²Transmission Pressure Switches
²Transmission Temperature Sensor
²Transmission Input Shaft Speed Sensor
²Transmission Output Shaft Speed Sensor
²Transaxle Gear Engagement
²Vehicle Speed
NOTE: PCM Outputs:
²Air Conditioning Clutch Relay
²Automatic Shut Down (ASD) and Fuel Pump
Relays
²Data Link Connector (PCI and SCI Transmit)
²Double Start Override
²EGR Solenoid
²Fuel Injectors
²Generator Field
²High Speed Fan Relay
²Idle Air Control Motor
²Ignition Coils
²Leak Detection Pump
²Low Speed Fan Relay
²MTV Actuator
²Proportional Purge Solenoid
²SRV Valve
²Speed Control Relay
²Speed Control Vent Relay
²Speed Control Vacuum Relay
²8 Volt Output
²5 Volt Output
²Torque Reduction Request
²Transmission Control Relay
²Transmission Solenoids
²Vehicle Speed
Based on inputs it receives, the powertrain control
module (PCM) adjusts fuel injector pulse width, idle
speed, ignition timing, and canister purge operation.
The PCM regulates the cooling fans, air conditioning
and speed control systems. The PCM changes gener-
ator charge rate by adjusting the generator field.
The PCM adjusts injector pulse width (air-fuel
ratio) based on the following inputs.
²Battery Voltage
²Intake Air Temperature Sensor
²Engine Coolant Temperature
²Engine Speed (crankshaft position sensor)
²Exhaust Gas Oxygen Content (heated oxygen
sensors)
²Manifold Absolute Pressure
²Throttle Position
The PCM adjusts engine idle speed through the
idle air control motor based on the following inputs.
²Brake Switch²Engine Coolant Temperature
²Engine Speed (crankshaft position sensor)
²Park/Neutral
²Transaxle Gear Engagement
²Throttle Position
²Vehicle Speed
The PCM adjusts ignition timing based on the fol-
lowing inputs.
²Intake Air Temperature
²Engine Coolant Temperature
²Engine Speed (crankshaft position sensor)
²Knock Sensor
²Manifold Absolute Pressure
²Park/Neutral
²Transaxle Gear Engagement
²Throttle Position
The automatic shut down (ASD) and fuel pump
relays are mounted externally, but turned on and off
by the powertrain control module through the same
circuit.
The camshaft and crankshaft signals are sent to
the powertrain control module. If the PCM does not
receive both signals within approximately one second
of engine cranking, it deactivates the ASD and fuel
pump relays. When these relays are deactivated,
power is shut off to the fuel injectors, ignition coils,
fuel pump and the heating element in each oxygen
sensor.
The PCM contains a voltage converter that
changes battery voltage to a regulated 8.0 volts. The
8.0 volts power the camshaft position sensor, crank-
shaft position sensor and vehicle speed sensor. The
PCM also provides a 5.0 volts supply for the engine
coolant temperature sensor, intake air temperature
sensor, manifold absolute pressure sensor and throt-
tle position sensor.
The PCM engine control strategy prevents reduced
idle speeds until after the engine operates for 320 km
(200 miles). If the PCM is replaced after 320 km (200
miles) of usage, update the mileage in new PCM. Use
the DRBIIItscan tool to change the mileage in the
PCM. Refer to the appropriate Powertrain Diagnostic
Manual and the DRBIIItscan tool.
TRANSMISSION CONTROL
CLUTCH VOLUME INDEX (CVI)
An important function of the PCM is to monitor
Clutch Volume Index (CVI). CVIs represent the vol-
ume of fluid needed to compress a clutch pack.
The PCM monitors gear ratio changes by monitor-
ing the Input and Output Speed Sensors. The Input,
or Turbine Speed Sensor sends an electrical signal to
the PCM that represents input shaft rpm. The Out-
put Speed Sensor provides the PCM with output
shaft speed information.
8E - 12 ELECTRONIC CONTROL MODULESRS
POWERTRAIN CONTROL MODULE (Continued)

By comparing the two inputs, the PCM can deter-
mine transaxle gear ratio. This is important to the
CVI calculation because the PCM determines CVIs
by monitoring how long it takes for a gear change to
occur (Fig. 10).
Gear ratios can be determined by using the DRB
Scan Tool and reading the Input/Output Speed Sen-
sor values in the ªMonitorsº display. Gear ratio can
be obtained by dividing the Input Speed Sensor value
by the Output Speed Sensor value.
For example, if the input shaft is rotating at 1000
rpm and the output shaft is rotating at 500 rpm,
then the PCM can determine that the gear ratio is
2:1. In direct drive (3rd gear), the gear ratio changes
to 1:1. The gear ratio changes as clutches are applied
and released. By monitoring the length of time it
takes for the gear ratio to change following a shift
request, the PCM can determine the volume of fluid
used to apply or release a friction element.
The volume of transmission fluid needed to apply
the friction elements are continuously updated for
adaptive controls. As friction material wears, the vol-
ume of fluid need to apply the element increases.
Certain mechanical problems within the clutch
assemblies (broken return springs, out of position
snap rings, excessive clutch pack clearance, improper
assembly, etc.) can cause inadequate or out-of-range
clutch volumes. Also, defective Input/Output Speed
Sensors and wiring can cause these conditions. The
following chart identifies the appropriate clutch vol-
umes and when they are monitored/updated:
CLUTCH VOLUMES
ClutchWhen Updated
Proper Clutch
Volume
Shift Sequence Oil Temperature Throttle Angle
L/R2-1 or 3-1 coast
downshift>70É <5É 35to83
2/4 1-2 shift
> 110É5 - 54É20 to 77
OD 2-3 shift 48 to 150
UD 4-3 or 4-2 shift > 5É 24 to 70
SHIFT SCHEDULES
As mentioned earlier, the PCM 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 PCM appropri-
ately adjusts the shift schedule. Refer to the follow-
ing chart to determine the appropriate operation
expected, depending on driving conditions.
Fig. 10 Example of CVI Calculation
1 - OUTPUT SPEED SENSOR
2 - OUTPUT SHAFT
3 - CLUTCH PACK
4 - SEPARATOR PLATE
5 - FRICTION DISCS
6 - INPUT SHAFT
7 - INPUT SPEED SENSOR
8 - PISTON AND SEAL
RSELECTRONIC CONTROL MODULES8E-13
POWERTRAIN CONTROL MODULE (Continued)

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
OPERATION - SENSOR RETURN - PCM INPUT
The sensor return circuit provides a low electrical
noise ground reference for all of the systems sensors.
The sensor return circuit connects to internal ground
circuits within the Powertrain Control Module
(PCM).
OPERATION - DATA BUS COMMUNICATION
RECEIVE - PCM INPUT
The PCM uses the SCI communication bus to pre-
form engine diagnostics and flash operations. The
transmission side of the PCM uses the SCI commu-
nication bus to flash new software. However, diagnos-tics is performed via the vehicles J1850 bus for the
transmission side of the PCM.
OPERATION - IGNITION SENSE - PCM INPUT
The ignition sense input informs the Powertrain
Control Module (PCM) that the ignition switch is in
the crank or run position.
OPERATION - PCM GROUND
Ground is provided through multiple pins of the
PCM connector. Depending on the vehicle there may
be as many as two different ground pins. There are
power grounds and sensor grounds.
8E - 14 ELECTRONIC CONTROL MODULESRS
POWERTRAIN CONTROL MODULE (Continued)

The power grounds are used to control the ground
side relays, solenoids, ignition coil or injectors. The
signal ground is used for any input that uses sensor
return for ground, and the ground side of any inter-
nal processing component.
The PCM case is shielded to prevent RFI and EMI.
The PCM case is grounded and must be firmly
attached to a good, clean body ground.
Internally all grounds are connected together, how-
ever there is noise suppression on the sensor ground.
For EMI and RFI protection the housing and cover
are also grounded separately from the ground pins.
OPERATION - 5 VOLT SUPPLY - PCM OUTPUT
The PCM supplies 5 volts to the following sensors:
²A/C pressure transducer
²Ambient Temperature sensor
²Battery temperature
²Camshaft Position Sensor (NGC)
²Crankshaft Position Sensor (NGC)
²Engine coolant temperature sensor
²Inlet Air Temperature Sensor
²Knock sensor
²Linear EGR solenoid (if equipped)
²Manifold absolute pressure sensor
²Oil Pressure Switch
²Throttle position sensor
STANDARD PROCEDURE
STANDARD PROCEDURE - OBTAINING
DIAGNOSTIC TROUBLE CODES
BULB CHECK
Key on: Bulb illuminated until vehicle starts, as
long as all once per trip (readiness) monitors com-
pleted. If monitors havenotbeen completed, then:
Key on: bulb check for about 5 to 8 seconds, lamp
then flashes if once per trip (readiness) monitors
havenotbeen completed until vehicle is started,
then MIL is extinguished.
OBTAINING DTC'S USING DRB SCAN TOOL
(1) Connect the DRB scan tool to the data link
(diagnostic) connector. This connector is located in
the passenger compartment; at the lower edge of
instrument panel; near the steering column.
(2) Turn the ignition switch on and access the
ªRead Faultº screen.
(3) Record all the DTC's and ªfreeze frameº infor-
mation shown on the DRB scan tool.
(4) To erase DTC's, use the ªErase Trouble Codeº
data screen on the DRB scan tool.Do not erase any
DTC's until problems have been investigated
and repairs have been performed.
STANDARD PROCEDURE - PINION FACTOR
SETTING
NOTE: This procedure must be performed if the
PCM has been replaced with a NEW or replacement
unit. Failure to perform this procedure will result in
an inoperative or improperly calibrated speedome-
ter.
The vehicle speed readings for the speedometer are
taken from the output speed sensor. The PCM must
be calibrated to the different combinations of equip-
ment (final drive and tires) available. Pinion Factor
allows the technician to set the Powertrain Control
Module initial setting so that the speedometer read-
ings will be correct. To properly read and/or reset the
Pinion Factor, it is necessary to use a DRBIIItscan
tool.
(1) Plug the DRBIIItscan tool into the diagnostic
connector located under the instrument panel.
(2) Select the Transmission menu.
(3) Select the Miscellaneous menu.
(4) Select Pinion Factor. Then follow the instruc-
tions on the DRBIIItscan tool screen.
STANDARD PROCEDURE - QUICK LEARN
PROCEDURE
The quick learn procedure requires the use of the
DRBIIItscan tool. This program allows the PCM to
recalibrate itself. This will provide the best possible
transaxle operation.
NOTE: The quick learn procedure should be per-
formed if any of the following procedures are per-
formed:
²Transaxle Assembly Replacement
²Powertrain Control Module Replacement
²Solenoid/Pressure Switch Assembly Replacement
²Clutch Plate and/or Seal Replacement
²Valve Body Replacement or Recondition
To perform the Quick Learn Procedure, the follow-
ing conditions must be met:
²The brakes must be applied
²The engine speed must be above 500 rpm
²The throttle angle (TPS) must be less than 3
degrees
²The shift lever position must stay until
prompted to shift to overdrive
²The shift lever position must stay in overdrive
after the Shift to Overdrive prompt until the
DRBIIItindicates the procedure is complete
²The calculated oil temperature must be above
60É and below 200É
RSELECTRONIC CONTROL MODULES8E-15
POWERTRAIN CONTROL MODULE (Continued)

(1) Plug the DRBIIItscan tool into the diagnostic
connector. The connector is located under the instru-
ment panel.
(2) Go to the Transmission screen.
(3) Go to the Miscellaneous screen.
(4) Select Quick Learn Procedure. Follow the
instructions of the DRBIIItto perform the Quick
Learn Procedure.
REMOVAL
REMOVAL - SBEC CONTROLLER
(1) Disconnect the negative battery cable.
(2) Remove the battery shield, refer to the Battery
section for more information.
(3) Remove the 2 upper PCM bracket bolts (Fig.
11).
(4) Remove the 2 PCM connectors.
(5) Remove the headlamp, refer to the Lamps sec-
tion for more information.
(6) Remove the lower PCM mounting bolt (Fig. 12).
(7) Remove PCM.
REMOVAL - NGC CONTROLLER
The PCM engine control strategy prevents reduced
idle speeds until after the engine operates for 320 km
(200 miles). If the PCM is replaced after 320 km (200
miles) of usage, update the mileage and vehicle iden-
tification number (VIN) in the new PCM. Use the
DRBIIItscan tool to change the millage and VIN in
the PCM. If this step is not done a Diagnostic Trou-
ble Code (DTC) may be set. Refer to the appropriate
Powertrain Diagnostic Manual and the DRBIIItscan
tool.
Fig. 11 PCM
1 - Attaching Bolts
Fig. 12 PCM LOWER BOLT
NGC CONTROLLER LOCATION
8E - 16 ELECTRONIC CONTROL MODULESRS
POWERTRAIN CONTROL MODULE (Continued)