transmission control module CHRYSLER VOYAGER 2005 Service Manual

GROUP TAB LOCATOR
Introduction
0Lubrication & Maintenance
2Suspension
3Differential & Driveline
5Brakes
7Cooling
8AAudio
8BChime/Buzzer
8EElectronic Control Modules
8FEngine Systems
8GHeated Systems
8HHorn
8IIgnition Control
8JInstrument Cluster
8LLamps
8MMessage Systems
8NPower Systems
8ORestraints
8PSpeed Control
8QVehicle Theft Security
8RWipers/Washers
8TNavigation/Telecommunication
8WWiring
9Engine
11Exhaust System
13Frame & Bumpers
14Fuel System
19Steering
21Transmission/Transaxle
22Tires/Wheels
23Body
24Heating & Air Conditioning
25Emissions Control
Component and System Index
Service Manual Comment Forms (Rear of Manual)

(5) Install the upper radiator mounts to the cross-
member bolts, if removed. Tighten to 8 N´m (70 in.
lbs.).
(6) Install the radiator upper hose to the support
clip (2.4L engine).
RADIATOR FAN RELAY
DESCRIPTION
The radiator fan relay is a solid state type and is
located on the front bumper reinforcment (Fig. 21).
Refer to WIRING DIAGRAMS for a circuit sche-
matic.
OPERATION
The solid state radiator fan relay is controlled by
the Powertrain Control Module (PCM) by way of a
Pulse Width Modulated (PWM) signal. The relay con-
trol circuit supplies a 12 volt signal to the PCM. The
PCM then pulses the ground circuit to achieve fan on
time. The relay provides a voltage to the fan motors
which is proportional to the pulse width it receives
from the PCM. The duty cycle ranges from 30% for
low speed operation, then ramps-up to 100% for high
speed operation. This fan control system provides
infinitely variable fan speeds, allowing for improved
fan noise, A/C performance, better engine cooling,
and additional vehicle power.
To control operation of the relay, the PCM looks at
inputs from:
²Engine coolant temperature
²A/C pressure transducer
²Ambient temperature from the body controller
²Vehicle speed
²Transmission oil temperature
The PCM uses these inputs to determine when the
fan should operate and at what speed. For further
information on fan operation, (Refer to 7 - COOL-
ING/ENGINE/RADIATOR FAN - OPERATION).
REMOVAL
(1) Open hood.
(2) Disconnect and isolate the battery negative
cable.
(3) Remove the radiator crossmember to front fas-
cia closure panel.
(4) Disconnect the relay electrical connector (Fig.
21).
(5) Remove the rivet attaching the relay to the
front bumper beam (Fig. 21).
(6) Remove the relay.
INSTALLATION
CAUTION: The relay mounting location is designed
to dissipate heat. Ensure the relay is securely
attached to prevent relay ªthermalº shutdown and
relay damage, resulting in possible engine over-
heating.
(1) Position relay and install a new rivet (Fig. 21).
(2) Connect electrical connector to relay.
(3) Install closure panel and attaching screws.
(4) Connect negative cable to battery.
Fig. 21 Radiator Fan Relay
1 - FRONT FASCIA
2 - FAN RELAY
3 - RIVET
4 - A/C CONDENSER (FRONT SIDE)
RSENGINE7-31
RADIATOR FAN (Continued)

When a PCM (SBEC) and the SKIM are replaced
at the same time perform the following steps in
order:
(1) Program the new PCM (SBEC)
(2) Program the new SKIM
(3) Replace all ignition keys and program them to
the new SKIM.
PROGRAMMING THE PCM (SBEC)
The SKIS Secret Key is an ID code that is unique
to each SKIM. This code is programmed and stored
in the SKIM, PCM and transponder chip (ignition
keys). When replacing the PCM it is necessary to
program the secret key into the new PCM using the
DRB III. Perform the following steps to program the
secret key into the PCM.
(1) Turn the ignition switch on (transmission in
park/neutral).
(2) Use the DRB III and select THEFT ALARM,
SKIM then MISCELLANEOUS.
(3) Select PCM REPLACED (GAS ENGINE).
(4) Enter secured access mode by entering the
vehicle four-digit PIN.
(5) Select ENTER to update PCM VIN.
NOTE: If three attempts are made to enter secure
access mode using an incorrect PIN, secured
access mode will be locked out for one hour. To
exit this lockout mode, turn the ignition to the RUN
position for one hour then enter the correct PIN.
(Ensure all accessories are turned off. Also monitor
the battery state and connect a battery charger if
necessary).
(6) Press ENTER to transfer the secret key (the
SKIM will send the secret key to the PCM).
(7) Press Page Back to get to the Select System
menu and select ENGINE, MISCELLANEOUS, and
SRI MEMORY CHECK.
(8) The DRB III will ask, Is odometer reading
between XX and XX? Select the YES or NO button on
the DRB III. If NO is selected, the DRB III will read,
Enter odometer Reading. Enter
the odometer reading from the Instrument Panel and
press ENTER.
PROGRAMMING THE SKIM
(1) Turn the ignition switch on (transmission in
park/neutral).
(2) Use the DRB III and select THEFT ALARM,
SKIM then MISCELLANEOUS.
(3) Select PCM REPLACED (GAS ENGINE).
(4) Program the vehicle four-digit PIN into SKIM.
(5) Select COUNTRY CODE and enter the correct
country.NOTE: Be sure to enter the correct country code. If
the incorrect country code is programmed into
SKIM, the SKIM must be replaced.
(6) Select YES to update VIN (the SKIM will learn
the VIN from the PCM).
(7) Press ENTER to transfer the secret key (the
PCM will send the secret key to the SKIM).
(8) Program ignition keys to SKIM.
NOTE: If the PCM and the SKIM are replaced at the
same time, all vehicle keys will need to be replaced
and programmed to the new SKIM.
PROGRAMMING IGNITION KEYS TO THE SKIM
(1) Turn the ignition switch on (transmission in
park/neutral).
(2) Use the DRB III and select THEFT ALARM,
SKIM then MISCELLANEOUS.
(3) Select PROGRAM IGNITION KEY'S.
(4) Enter secured access mode by entering the
vehicle four-digit PIN.
NOTE: A maximum of eight keys can be learned to
each SKIM. Once a key is learned to a SKIM it (the
key) cannot be transferred to another vehicle.
If ignition key programming is unsuccessful, the
DRB III will display one of the following messages:
Programming Not Attempted - The DRB III
attempts to read the programmed key status and
there are no keys programmed into SKIM memory.
Programming Key Failed (Possible Used Key From
Wrong Vehicle) - SKIM is unable to program key due
to one of the following:
²faulty ignition key transponder
²ignition key is programmed to another vehicle.
8 Keys Already Learned, Programming Not Done -
SKIM transponder ID memory is full.
(5) Obtain ignition keys to be programmed from
customer (8 keys maximum).
(6) Using the DRB III, erase all ignition keys by
selecting MISCELLANEOUS and ERASE ALL CUR-
RENT IGN. KEYS.
(7) Program all ignition keys.
Learned Key In Ignition - Ignition key transponder
ID is currently programmed in SKIM memory.
BODY CONTROL MODULE
DESCRIPTION
The Body Control Module (BCM) is located in the
passenger compartment, attached to the bulkhead
underneath the left side of the instrument panel.
8E - 2 ELECTRONIC CONTROL MODULESRS
ELECTRONIC CONTROL MODULES (Continued)

The BCM utilizes integrated circuitry and informa-
tion carried on the Programmable Communications
Interface (PCI) data bus network along with many
hard wired inputs to monitor many sensor and
switch inputs throughout the vehicle. In response to
those inputs, the internal circuitry and programming
of the BCM allow it to control and integrate many
electronic functions and features of the vehicle
through both hard wired outputs and the transmis-
sion of electronic message outputs to other electronic
modules in the vehicle over the PCI data bus.
OPERATION
The Body Control Module (BCM) supplies vehicle
occupants with visual and audible information and
controls various vehicle functions. To provide and
receive information, the BCM is interfaced to the
vehicle's serial bus communications network, referred
to as the Programmable Communications Interface
(PCI) bus.
This network consists of the;
²Powertrain Control Module (PCM)
²Transmission Control Module (TCM)
²Mechanical Instrument Cluster (MIC)
²Occupant Restraint Controller (ORC)
²Compass/Mini-Trip Computer (CMTC)
²Electronic Vehicle Information Center (EVIC)
²Controller Antilock Brake (CAB)
²HVAC Control Module
²Sliding Door Control Modules (driver and pas-
senger side doors)
²Power Liftgate Module (PLG)
²Audio system equipped with RAZ, RBU, RBK,
and RBB radios.
²Sentry Key Remote Entry Module (SKREEM).
²Side Impact Airbag Control Module (SIACM)²Memory Seat Module (MSM)
²Sentry Key Immobilizer Module (SKIM)
The BCM is operational when battery power is
supplied to the module.
The BCM provides the following features:
²Power Door Locks
²Automatic Door Locks
²Battery Protection - The BCM will automatically
turn off all exterior lamps after 3 minutes, and all
interior lamps after 15 minutes after the ignition is
turned off, if they are not turned off by the driver.
²Chime Control
²Compass/Mini-Trip support.
²Interior Lighting (Courtesy/Reading Lamps)
²BCM Diagnostic Reporting
²Electronic Liftgate Release (with Power Door
Locks)
²Exterior Lighting
²Headlamp Time Delay (with/without Automatic
Headlamps)
²Illuminated Entry
²Fade to Off Interior Lamps - This feature dims
the interior lighting (courtesy lamps) gradually if the
BCM does not receive any new inputs that would
cause the interior lamps to remain on.
²Pulse Width Modulated Instrument Panel Dim-
ming
²Door Lock Inhibit - This feature disables the
door lock functions if the key is in the ignition and
either front door is ajar. Pressing the Remote Keyless
Entry (RKE) lock/unlock button under these condi-
tions result in normal lock/unlock activation.
The BCM has the ability to LEARN additional fea-
tures in the vehicle, provided the appropriate switch
input and PCI data bus messages are received. Refer
to the LEARNED FEATURES table.
LEARNED FEATURES
FEATURE LEARNING KEY
REAR WIPER CONTROL ON HVAC CONTROL ON
INSTRUMENT PANELPCI BUS MESSAGE RECEIVED FROM HVAC
CONTROL
AUTOMATIC HEADLAMPS PCI MESSAGE FROM OVERHEAD OR HEADLAMP
SWITCH POSITION (AUTO)
REMOTE KEYLESS ENTRY SKREEM MESSAGE RECEIVED FROM MODULE
FRONT FOG LAMPS HEADLAMP SWITCH POSITION (PARK W/FRONT
FOG LAMPS)
POWER SLIDING DOOR PCI IFR RECEIVED FROM MODULE
THE BCM HAS FOUR SWITCH INPUTS FOR THE POWER SLIDING DOOR FEATURE; LOCATED IN THE
OVERHEAD CONSOLE ARE THE LEFT AND RIGHT SIDE SLIDING DOOR SWITCHES TO ACTIVATE EITHER
OR BOTH SLIDING DOORS UNDER THE PROPER CONDITIONS. ALSO ARE B-PILLAR SWITCHES LOCATED
ON THE LEFT AND RIGHT B-PILLAR POSTS.
POWER LIFTGATE PCI IFR RECEIVED FROM MODULE
RSELECTRONIC CONTROL MODULES8E-3
BODY CONTROL MODULE (Continued)

FRONT CONTROL MODULE
DESCRIPTION
The Front Control Module (FCM) is a micro con-
troller based module located in the engine compart-
ment. The FCM mates to the Power Distribution
Center (PDC) to form the Integrated Power Module
(IPM). The IPM connects directly to the battery and
provides the primary means of circuit protection and
power distribution for all vehicle electrical systems.
The FCM controls power to some of these vehicle sys-
tems electrical and electromechanical loads based on
inputs received from hard wired switch inputs and
data received on the Programmable Communications
Interface (PCI) data bus.
For information on the IPM, (Refer to 8 - ELEC-
TRICAL/POWER DISTRIBUTION/INTEGRATED
POWER MODULE - DESCRIPTION)
OPERATION
As messages are sent over the Programmable Com-
munications Interface (PCI) data bus, the Front Con-
trol Module (FCM) reads these messages and controls
power to some of the vehicles electrical systems by
completing the circuit to ground (low side driver) or
completing the circuit to 12 volt power (high side
driver).
The following functions arecontrolledby the
Front Control Module:
²Accessory Relay Actuation
²Brake Transmission Shift Interlock Functions
(BTSI - gas engine only)
²Diesel Cabin Heater (Diesel Engine Vehicles)
²Electronic Back Light (EBL) Rear Defogger
²Front and Rear Blower Motor Relay Actuation
²Front Fog Lamp Relay Actuation
²Washer Motor (front and rear)
²Front Windshield Wiper ªHIº & ªLOº Relay
Actuation
²Front Windshield Wiper ªONº Relay Actuation
²Headlamp Power with Voltage Regulation
²Horn Relay Actuation
²Headlamp Washer Relay Actuation (IF
EQUIPPED - EXPORT ONLY)
²Name Brand Speaker (NBS) Relay Actuation
²Park Lamp Relay Actuation
The following inputs areReceived/Monitoredby
the Front Control Module:
²Ambient Temperature Sensing
²Back-Up switch
²Brake Fluid Level
²B+ Connection Detection
²Engine Crank Signal (Diesel Engine Vehicles)
²Horn Input
²Ignition Switch Start Only
²Ignition Switch Run and Start Only²Stop Lamp Sense
²Washer Fluid Level
²Windshield Wiper Park
DIAGNOSIS AND TESTING
FRONT CONTROL MODULE
The Front Control Module (FCM) is a printed cir-
cuit board based module with a on-board micro-pro-
cessor. The FCM interfaces with other electronic
modules in the vehicle via the Programmable Com-
munications Interface (PCI) data bus. In order to
obtain conclusive testing the PCI data bus and all of
the electronic modules that provide inputs to, or
receive outputs from the FCM must be checked. All
PCI communication faults must be resolved prior to
further diagnosing any front control module related
issues.
The FCM was designed to be diagnosed with an
appropriate diagnostic scan tool, such as the DRB
IIIt. The most reliable, efficient, and accurate means
to diagnose the front control module requires the use
of a DRB IIItscan tool and the proper Body Diag-
nostic Procedures manual.
Before any testing of the FCM is attempted, the
battery should be fully charged and all wire harness
and ground connections inspected around the affected
areas on the vehicle.
REMOVAL
(1) Disconnect and isolate the negative and posi-
tive battery cables from the battery.
(2) Remove the battery (Refer to 8 - ELECTRI-
CAL/BATTERY SYSTEM/BATTERY - REMOVAL).
(3) Using a long flat-bladed screwdriver, gently
twist the Integrated Power Module (IPM) retaining
clip outboard to free the IPM from its mounting
bracket (Fig. 5). Rotate IPM upward to access the
Front Control Module (FCM) retaining screws.
(4) Remove the front control module retaining
screws.
(5) Pull the FCM straight from the IPM assembly
to disconnect the electrical connector (Fig. 6) and
remove the FCM from the vehicle.
INSTALLATION
NOTE: Front Control Module must be programmed
to the correct radio EQ curve using the DRB IIIT.
This will ensure that the audio system is operating
correctly.
(1) Install the Front Control Module (FCM) in the
Integrated Power Module (IPM) assembly by pushing
the 49-way electrical connector straight in.
RSELECTRONIC CONTROL MODULES8E-7

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)