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tion switch is in any position except On, and elec-
tronic messages are received over the PCI data bus
from the BCM indicating that the exterior lights are
On with the ignition switch in any position except
On, and the status of the driver side front door is not
closed. The BCM uses internal programming and
hard wired inputs from the left (lighting) control
stalk of the multi-function switch, the ignition
switch, and the driver side front door ajar switch to
determine the proper messages to send to the EMIC.
These chimes will continue to sound until the exte-
rior lighting is turned Off, until the ignition switch is
turned to the On position, or until the status of the
driver side front door ajar input changes from not
closed to closed, whichever occurs first.
²Key-In-Ignition Warning- The EMIC chime
tone generator will generate repetitive ªbong-likeº
chime tones at a fast rate when the ignition switch is
in any position except On, and electronic messages
are received over the PCI data bus from the BCM
indicating that the key is in the ignition lock cylinder
with the ignition switch in any position except On,
and the driver side front door is not closed. The BCM
internal programming and hard wired inputs from
the key-in ignition circuitry of the ignition switch,
the ignition switch, and the driver side front door
ajar switch to determine the proper messages to send
to the EMIC. These chimes will continue to sound
until the key is removed from the ignition lock cylin-
der, until the ignition switch is turned to the On
position, or until the status of the driver side front
door ajar input changes from not closed to closed,
whichever occurs first.
²Low Coolant Warning- On vehicles equipped
with a diesel engine, the EMIC chime tone generator
will generate a single ªbong-likeº chime tone when
the ignition switch is first turned to the On position
and a hard wired input from the engine coolant level
sensor to the EMIC indicates that the coolant level is
low for more than about one-quarter second. Any
time after the ignition switch is first turned to the
On position, the EMIC uses internal programming to
check the status of the engine coolant level sensor
inputs about once every second, then adjusts an
internal counter up or down based upon the status of
this input. When the counter accumulates thirty
inputs indicating that the coolant level is low, a sin-
gle chime tone is sounded. This strategy is intended
to reduce the effect that coolant sloshing within the
coolant reservoir can have on reliable chime warning
operation. This warning will only occur once during
an ignition cycle.
²Low Fuel Warning- Each time the ignition
switch is turned to the On position, the EMIC chime
tone generator will generate a single ªbong-likeº
chime tone the first time an electronic message isreceived over the PCI data bus from the PCM
requesting ªLow Fuelº indicator illumination. The
chime will only occur a second time during the same
ignition cycle if another electronic message has been
received from the PCM indicating that there is an
increase in the fuel level equal to about 3 liters (0.8
gallon), then a subsequent electronic message from
the PCM requests ªLow Fuelº indicator illumination.
This strategy combined with filtering performed by
the internal programming of the PCM on the fuel
tank sending unit input is intended to reduce the
possibility of fuel sloshing within the fuel tank caus-
ing multiple low fuel warning chimes during a given
ignition cycle. The EMIC will also respond with the
low fuel warning chime when electronic fuel level
messages are received from the PCM indicating that
the hard wired input to the PCM from the fuel tank
sending unit is an open circuit (greater than full), or
a short circuit (less than empty).
²Low Washer Fluid Warning- The EMIC
chime tone generator will generate a single ªbong-
likeº chime tone when the ignition switch is turned
to the On position and a hard wired input from the
washer fluid level switch to the EMIC indicates the
washer fluid is low for more than about one-quarter
second. Any time after the ignition switch is first
turned to the On position, the EMIC uses internal
programming to check the status of the washer fluid
level switch inputs about once every second, then
adjusts an internal counter up or down based upon
the status of this input. When the counter accumu-
lates thirty inputs indicating that the washer fluid
level is low, a single chime tone is sounded. This
strategy is intended to reduce the effect that fluid
sloshing within the washer reservoir can have on
reliable chime warning operation. This warning will
only occur once during an ignition cycle.
²Overspeed Warning- The EMIC chime tone
generator will generate repetitive ªbong-likeº chime
tones at a slow rate when the ignition switch is in
the On position, and an electronic message received
over the PCI data bus from the PCM indicates that
the vehicle speed is over a programmed speed value.
The PCM uses internal programming and distance
pulse information received over a hard wired vehicle
speed pulse input from the BCM to determine the
proper vehicle speed messages to send to the EMIC.
The BCM uses an internally programmed electronic
pinion factor and a hard wired input from the rear
wheel speed sensor to calculate the proper distance
pulse information to send to the PCM. The electronic
pinion factor represents the proper tire size and axle
ratio information for the vehicle. These chimes will
continue to sound until the vehicle speed messages
are below the programmed speed value, or until the
ignition switch is turned to the Off position, which-
8B - 4 CHIME/BUZZERKJ
CHIME WARNING SYSTEM (Continued)

ever occurs first. The overspeed warning feature is
only enabled on a BCM that has been programmed
with a Middle East Gulf Coast Country (GCC) coun-
try code.
²No Airbag Indicator Message Warning- The
EMIC chime tone generator will generate one, short,
ªbong-likeº chime tone and turn on the ªAirbagº indi-
cator when the ignition switch is in the On position,
and a PCI data bus ªAirbagº indicator on or off mes-
sage is not received from the ACM for six consecutive
seconds.
²No Antilock Brake Indicator Message Warn-
ing- The EMIC chime tone generator will generate
one, short, ªbong-likeº chime tone and turn on the
ªABSº indicator when the ignition switch is in the On
position, and a PCI data bus ªABSº indicator on or
off message is not received from the CAB for six con-
secutive seconds.
²No Fuel Level Message Warning- The EMIC
chime tone generator will generate one, short, ªbong-
likeº chime tone and turn on the ªLow Fuelº indica-
tor when the ignition switch is in the On position,
and a PCI data bus fuel level message is not received
from the PCM for twelve consecutive seconds.
²Remote Keyless Entry Transmitter Pro-
gramming- On vehicles so equipped, the EMIC
chime tone generator will generate a single ªbong-
likeº chime tone when an electronic message is
received over the PCI data bus from the BCM indi-
cating that a Remote Keyless Entry (RKE) transmit-
ter has been successfully programmed by the
customer into the RKE module memory.
²Sentry Key Immobilizer System Transpon-
der Programming- On vehicles so equipped, the
EMIC chime tone generator will generate a single
ªbong-likeº chime tone when an electronic message is
received over PCI data bus message from the Sentry
Key Immobilizer Module (SKIM) indicating that the
Sentry Key Immobilizer System (SKIS) has been
placed in the ªCustomer Learnº programming mode,
and again each time a new SKIS transponder has
been successfully programmed by the customer.
²Turn Signal Cancel Warning- The EMIC
chime tone generator will generate repetitive ªbong-
likeº chime tones at a slow rate when the vehicle is
driven for a distance of about 3.2 kilometers (about
two miles) with a turn signal indicator flashing. The
EMIC uses an electronic message received over the
PCI data bus from the PCM, and a hard wired input
from the turn signal switch circuitry of the multi-
function switch to determine when to sound the turn
signal cancel warning. The PCM uses internal pro-
gramming and distance pulse information received
over a hard wired vehicle speed pulse input from the
BCM to determine the proper vehicle speed messages
to send to the EMIC. The BCM uses an internallyprogrammed electronic pinion factor and a hard
wired input from the rear wheel speed sensor to cal-
culate the proper distance pulse information to send
to the PCM. The electronic pinion factor represents
the proper tire size and axle ratio information for the
vehicle. These chimes will continue to sound until
the turn signal is turned Off, until the hazard warn-
ing system is turned On, or until the ignition switch
is turned to the Off position, whichever occurs first.
²Water-In-Fuel Warning- On vehicles equipped
with a diesel engine, each time the ignition switch is
turned to the On position, the EMIC chime tone gen-
erator will generate a single ªbong-likeº chime tone
the first time an electronic message is received over
the PCI data bus from the PCM requesting ªWater-
in-Fuelº indicator illumination. The PCM uses inter-
nal programming and a hard wired input from the
water-in-fuel sensor to determine the proper water-
in-fuel messages to send to the EMIC. This warning
will only occur once during an ignition cycle.
The EMIC provides chime service for all available
features in the chime warning system. The EMIC
relies upon its internal programming and hard wired
inputs from the turn signal (multi-function) switch,
the washer fluid level switch, and the engine coolant
level sensor (diesel engine only) to provide chime ser-
vice for the turn signal cancel warning, the low
washer fluid warning, and the low coolant warning
respectively. The EMIC relies upon electronic mes-
sage inputs received from other electronic modules
over the PCI data bus network to provide chime ser-
vice for all of the remaining chime warning system
features. Upon receiving the proper inputs, the EMIC
activates the integral chime tone generator to pro-
vide the audible chime warning to the vehicle opera-
tor. The internal programming of the EMIC
determines the priority of each chime request input
that is received, as well as the rate and duration of
each chime tone that is to be generated. See the own-
er's manual in the vehicle glove box for more infor-
mation on the features provided by the chime
warning system.
The hard wired chime warning system inputs to
the EMIC, as well as other hard wired circuits for
this system may be diagnosed and tested using con-
ventional diagnostic tools and procedures. However,
conventional diagnostic methods may not prove con-
clusive in the diagnosis of the EMIC, the PCI data
bus network, or the electronic message inputs used
by the EMIC to provide chime warning system ser-
vice. The most reliable, efficient, and accurate means
to diagnose the EMIC, the PCI data bus network,
and the electronic message inputs for the chime
warning system requires the use of a DRBIIItscan
tool. Refer to the appropriate diagnostic information.
KJCHIME/BUZZER 8B - 5
CHIME WARNING SYSTEM (Continued)

ELECTRONIC CONTROL MODULES
TABLE OF CONTENTS
page page
ELECTRONIC CONTROL MODULES
STANDARD PROCEDURE - PCM/SKIM
PROGRAMMING.......................1
BODY CONTROL MODULE
DESCRIPTION..........................2
OPERATION............................5
DIAGNOSIS AND TESTING - BODY CONTROL
MODULE.............................7
REMOVAL.............................7
INSTALLATION..........................7
COMMUNICATION
DESCRIPTION..........................8
OPERATION............................8
CONTROLLER ANTILOCK BRAKE
REMOVAL.............................10
INSTALLATION.........................10
DATA LINK CONNECTOR
DESCRIPTION - DATA LINK CONNECTOR....10
OPERATION - DATA LINK CONNECTOR......10
POWERTRAIN CONTROL MODULE
DESCRIPTION
DESCRIPTION - PCM..................11
DESCRIPTION - MODES OF OPERATION . . . 11
DESCRIPTION - 5 VOLT SUPPLIES.......13
DESCRIPTION - IGNITION CIRCUIT SENSE . 13DESCRIPTION - POWER GROUNDS......13
DESCRIPTION - SENSOR RETURN.......14
OPERATION
OPERATION - PCM....................14
OPERATION - 5 VOLT SUPPLIES.........15
OPERATION - IGNITION CIRCUIT SENSE . . . 15
REMOVAL.............................15
INSTALLATION.........................15
SENTRY KEY IMMOBILIZER MODULE
DESCRIPTION.........................15
OPERATION...........................16
REMOVAL.............................17
INSTALLATION.........................18
TRANSMISSION CONTROL MODULE
DESCRIPTION.........................18
OPERATION...........................18
STANDARD PROCEDURE - TCM QUICK
LEARN..............................21
HEATED SEAT MODULE
DESCRIPTION.........................21
OPERATION...........................21
DIAGNOSIS AND TESTING - HEATED SEAT
MODULE............................22
REMOVAL.............................24
INSTALLATION.........................24
ELECTRONIC CONTROL
MODULES
STANDARD PROCEDURE - PCM/SKIM
PROGRAMMING
NOTE: Before replacing the PCM for a failed driver,
control circuit, or ground circuit, be sure to check
the related component/circuit integrity for failures
not detected due to a double fault in the circuit.
Most PCM driver/control circuit failures are caused
by internal component failures (i.e. relays and sole-
noids) and shorted circuits (i.e. pull-ups, drivers,
and switched circuits). These failures are difficult to
detect when a double fault has occurred and only
one DTC has been set.
When a PCM (JTEC) and the SKIM are replaced
at the same time, perform the following steps in
order:
(1) Program the new PCM (JTEC).(2) Program the new SKIM.
(3) Replace all ignition keys and program them to
the new SKIM.
PROGRAMMING THE PCM (JTEC)
The SKIS Secret Key is an ID code that is unique
to each SKIM. This code is programmed and stored
in the SKIM, the PCM, and the ignition key tran-
sponder chip(s). When replacing the PCM, it is nec-
essary to program the secret key into the new PCM
using the DRBIIItscan tool. Perform the following
steps to program the secret key into the PCM.
(1) Turn the ignition switch to the On position
(transmission in Park/Neutral).
(2) Use the DRBIIItand 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.
KJELECTRONIC CONTROL MODULES 8E - 1

NOTE: If three attempts are made to enter secured
access mode using an incorrect PIN, secured
access mode will be locked out for one hour. To
exit this lockout mode, turn the ignition switch to
the ON 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 DRBIIItwill ask, ªIs odometer reading
between XX and XX?º Select the YES or NO button
on the DRBIIIt. If NO is selected, the DRBIIItwill
read, ªEnter Odometer Reading (From I.P. odome-
ter)º. Enter the odometer reading from the instru-
ment cluster and press ENTER.
PROGRAMMING THE SKIM
(1) Turn the ignition switch to the On position
(transmission in Park/Neutral).
(2) Use the DRBIIItand 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, it cannot be changed and 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 the SKIM.
NOTE: If the PCM and the SKIM are replaced at the
same time, all vehicle ignition keys will need to be
replaced and programmed to the new SKIM.
PROGRAMMING IGNITION KEYS TO THE SKIM
(1) Turn the ignition switch to the On position
(transmission in Park/Neutral).
(2) Use the DRBIIItand 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.
(5) Obtain ignition keys to be programmed from
the customer (8 keys maximum).
(6) Using the DRBIIIt, erase all ignition keys by
selecting MISCELLANEOUS, and ERASE ALL CUR-
RENT IGN. KEYS.
(7) Program all of the ignition keys.
If ignition key programming is unsuccessful, the
DRBIIItwill display one of the following messages:
²Programming Not Attempted- The DRBIIIt
attempts to read the programmed key status and
there are no keys programmed into SKIM memory.
²Programming Key Failed (Possible Used
Key From Wrong Vehicle)- SKIM is unable to pro-
gram an ignition key transponder due to one of the
following:
²The ignition key transponder is faulty.
²The ignition key transponder is or has been
already programmed to another vehicle.
²8 Keys Already Learned, Programming Not
Done- The SKIM transponder ID memory is full.
²Learned Key In Ignition- The ID for the igni-
tion key transponder currently in the ignition lock
cylinder is already programmed in SKIM memory.
BODY CONTROL MODULE
DESCRIPTION
A Body Control Module (BCM) is concealed behind
the driver side end of the instrument panel in the
passenger compartment, where it is secured to the
fuse panel side of the Junction Block (JB) with four
screws (Fig. 1). The JB is the interface between the
body, the instrument panel, and the headlamp and
dash wire harnesses. The JB also contains the fuses
and relays used for the interior electrical system of
the vehicle. The BCM is enclosed in a molded plastic
housing with two integral external connector recepta-
cles that connect it to the vehicle electrical system
through two take outs with connectors from the
instrument panel wire harness (Fig. 2). The BCM
also has an integral interface connector concealed on
the back side of the unit that joins it through a con-
nector receptacle that is integral to the JB housing to
the circuitry within the JB. This connector is referred
to as the JB-BCM connector. The combined BCM and
JB are sometimes referred to as the Junction Block
Module (JBM).
8E - 2 ELECTRONIC CONTROL MODULESKJ
ELECTRONIC CONTROL MODULES (Continued)

There are two different versions of the BCM: base
and premium. The base BCM is a subset of the com-
ponents in the premium version. Basically, the base
version BCM does not support the following features:
Compass Mini-Trip Computer (CMTC), fog lamps
(front and/or rear), Remote Keyless Entry (RKE),
remote radio switches, or Vehicle Theft Security Sys-
tem (VTSS). Both versions of the BCM utilize inte-
grated circuitry and information carried on the
Programmable Communications Interface (PCI) databus 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 out-
puts and the transmission of electronic message out-
puts to other electronic modules in the vehicle over
the PCI data bus. The electronic functions and fea-
tures that the BCM supports or controls include the
following:
²A/C Select Switch Status- The BCM monitors
an input from, and transmits the status of the A/C
switch on the heater-A/C control.
²Ambient Temperature Data- The premium
BCM monitors and transmits the ambient tempera-
ture sensor input data.
²Cargo Lamp Disable- The BCM monitors an
input from the cargo lamp switch to provide an inte-
rior lighting disable feature.
²Chimes- The chime tone generator is located
on the ElectroMechanical Instrument Cluster (EMIC)
circuit board, but the EMIC goes to sleep with the
ignition switch in the Off position. The BCM provides
a wake-up output to the EMIC based upon inputs
from the key-in ignition switch or the exterior light-
ing switch, then sends electronic chime request mes-
sages to the EMIC for the headlamps-on warning
and key-in ignition warning.
²Door Lock Inhibit- The BCM monitors the
key-in ignition switch and the driver side front door
ajar switch to provide a door lock inhibit feature.
²Exterior Lamp Load Shedding- The BCM
provides a battery saver feature which will automat-
ically turn off exterior lamps that remain on after a
timed interval.
²Exterior Lamp Status- The BCM monitors
the status of the park lamp, low beam, high beam or
Daytime Running Lamp (DRL - Canada only), front
fog lamp (optional), and rear fog lamp (in required
markets only) relays.
²Exterior Lighting Control- The BCM pro-
vides exterior lamp control for standard head and
park lamps, as well as Daytime Running Lamps
(DRL - Canada only), front fog lamps (optional), and
rear fog lamps (in required markets only). This
includes support for features including optical horn
(also known as flash-to-pass) and headlamp time
delay.
²Flip-Up Glass Control- The BCM monitors
the tailgate cylinder lock switch, the tailgate handle
switch, the Remote Keyless Entry (RKE) module
inputs and the rear wiper switch to provide control
for the rear flip-up glass actuator.
Fig. 1 Body Control Module Location
1 - DRIVER DOOR
2 - INSTRUMENT PANEL END BRACKET
3 - JUNCTION BLOCK
4 - BODY CONTROL MODULE
Fig. 2 Body Control Module
1 - BODY CONTROL MODULE (FRONT VIEW)
2 - REMOTE KEYLESS ENTRY MODULE RECEPTACLE
3 - BCM-RKE CONNECTOR
4 - BODY CONTROL MODULE (BACK VIEW)
5 - JB-BCM CONNECTOR
6 - CONNECTOR RECEPTACLE (2)
KJELECTRONIC CONTROL MODULES 8E - 3
BODY CONTROL MODULE (Continued)

²Fog Lamp Control- The premium BCM pro-
vides fog lamp control for front fog lamps (optional),
and rear fog lamps (in required markets only).
²Front Wiper System Status- The BCM moni-
tors the status of the front wiper motor park switch.
²Fuel Economy and Distance to Empty Cal-
culations- The BCM calculates and transmits the
fuel economy and Distance To Empty (DTE) data.
²Headlamp Time Delay- The BCM provides a
headlamp time delay feature with the ignition switch
in the Off position.
²Heated Rear Glass Control- The BCM pro-
vides control and timer functions for the heated rear
glass feature and transmits the system status.
²Ignition On/Off Timer- The BCM monitors
and transmits the elapsed ignition On timer data
and monitors the ignition Off time.
²Ignition Switch Position Status- The BCM
monitors and transmits the status of the ignition
switch.
²Instrument Panel Dimming- The BCM mon-
itors and transmits the selected illumination inten-
sity level of the panel lamps dimmer switch.
²Interior Lamp Load Shedding- The BCM
provides a battery saver feature which will automat-
ically turn off all interior lamps that remain on after
a timed interval.
²Interior Lighting Control- The BCM moni-
tors inputs from the interior lighting switch, the door
ajar switches, the flip-up glass ajar switch, the tail-
gate ajar switch, the cargo lamp switch, the reading
lamp switches, and the Remote Keyless Entry (RKE)
module to provide courtesy lamp control. This
includes support for timed illuminated entry with
theater-style fade-to-off and courtesy illumination
defeat features.
²Intermittent Wipe and Front Wiper System
Control- The BCM monitors inputs from the front
wiper and washer switch and the front wiper motor
park switch to provide front wiper system control
through the wiper on/off and high/low relays. This
includes support for adjustable intermittent wipe,
mist wipe (also known as pulse wipe), and wipe-after-
wash features.
²Key-In-Ignition Switch Status- The BCM
monitors and transmits the status of the key-in-igni-
tion switch.
²Panic Mode- The BCM provides support for
the Remote Keyless Entry (RKE) system panic mode
feature.
²Parade Mode- The BCM provides a parade
mode (also known as funeral mode) that allows the
interior Vacuum Fluorescent Displays (VFD) to be
illuminated at full intensity while driving in daylight
with the exterior lamps On.²Power Locks- The BCM monitors inputs from
the power lock switches and the Remote Keyless
Entry (RKE) module (optional) to provide control of
the power lock motors through outputs to the lock,
unlock, and driver unlock (RKE only) relays. This
includes support for rolling door locks (also known as
automatic door locks) and a door lock inhibit mode.
²Programmable Features- The BCM provides
support for several standard and optional program-
mable features, including: rolling door locks, head-
lamp time delay interval, Remote Keyless Entry
(RKE) driver-door-only or unlock-all-doors, RKE opti-
cal chirp, and RKE audible chirp.
²Remote Keyless Entry- The premium BCM
provides the optional Remote Keyless Entry (RKE)
system features, including support for the RKE Lock,
Unlock (with optional driver-door-only unlock, and
unlock-all-doors), rear flip-up glass control, Panic,
audible chirp, optical chirp, and illuminated entry
modes, as well as the ability to be programmed to
recognize up to four RKE transmitters.
²Rolling Door Locks- The BCM provides sup-
port for the power lock system rolling door locks fea-
ture (also known as automatic door locks).
²Tailgate and Flip-Up Glass Ajar Status- The
BCM monitors and transmits the status of the tail-
gate and rear flip-up glass ajar switches.
²Remote Radio Switch Interface- The pre-
mium BCM monitors and transmits the status of the
optional remote radio switches.
²Self-Diagnostics- The BCM provides support
for diagnostics through communication with the
DRBIIItscan tool over the PCI data bus network.
Each analog and digital input can be verified, and
each output can be actuated through the use of this
diagnostic protocol. The BCM also stores Diagnostic
Trouble Codes (DTCs) to assist in troubleshooting
this unit.
²Vacuum Fluorescent Display Synchroniza-
tion- The BCM transmits panel lamp intensity data
which allows modules with Vacuum Fluorescent Dis-
plays (VFD) to coordinate their illumination inten-
sity.
²Vehicle Speed System- The BCM monitors a
vehicle speed input from the vehicle speed sensor
(without Antilock Brake System [ABS]) or from the
Controller Antilock Brake (CAB)(with ABS), calcu-
lates the vehicle speed based upon a programmed
axle ratio/tire size (electronic pinion factor), and
transmits the vehicle speed information to the Pow-
ertrain Control Module (PCM) on a hard wired out-
put circuit.
²Vehicle Theft Security System- The pre-
mium BCM monitors inputs from the door cylinder
lock switches, the tailgate cylinder lock switch, the
door ajar switches, the tailgate ajar switch, the
8E - 4 ELECTRONIC CONTROL MODULESKJ
BODY CONTROL MODULE (Continued)

flip-up glass ajar switch, the hood ajar switch (in
required markets only), and the Remote Keyless
Entry (RKE) module to control the features of the
optional Vehicle Theft Security System (VTSS).
Hard wired circuitry connects the BCM to the elec-
trical system of the vehicle. These hard wired circuits
are integral to several wire harnesses, which are
routed throughout the vehicle and retained by many
different methods. These circuits may be connected to
each other, to the vehicle electrical system and to the
BCM through the use of a combination of soldered
splices, splice block connectors, and many different
types of wire harness terminal connectors and insu-
lators. Refer to the appropriate wiring information.
The wiring information includes wiring diagrams,
proper wire and connector repair procedures, further
details on wire harness routing and retention, as well
as pin-out and location views for the various wire
harness connectors, splices and grounds.
Many of the electronic features in the vehicle con-
trolled or supported by the BCM are programmable
using a customer programming procedure or the
DRBIIItscan tool. In addition, the BCM software is
Flash compatible, which means it can be repro-
grammed using Flash reprogramming procedures.
However, if any of the BCM hardware components is
damaged or faulty, the entire BCM unit must be
replaced.
OPERATION
The microprocessor-based Body Control Module
(BCM) monitors many hard wired switch and sensor
inputs as well as those resources it shares with other
electronic modules in the vehicle through its commu-
nication over the Programmable Communications
Interface (PCI) data bus network. The internal pro-
gramming and all of these inputs allow the BCM
microprocessor to determine the tasks it needs to
perform and their priorities, as well as both the stan-
dard and optional features that it should provide.
The BCM programming then performs those tasks
and provides those features through both PCI data
bus communication with other electronic modules
and through hard wired outputs through a number of
driver circuits, relays, and actuators. These outputs
allow the BCM the ability to control numerous acces-
sory systems in the vehicle.
The BCM operates on battery current received
through a fuse in the Junction Block (JB) on a non-
switched fused B(+) circuit, through another fuse in
the JB on a fused ignition switch output (run-start)
circuit, and through a third fuse in the JB on a fused
ignition switch output (run-acc) circuit. This arrange-
ment allows the BCM to provide some features
regardless of the ignition switch position, while other
features will operate only with the ignition switch inthe On, Start, and/or Accessory positions. All of the
battery current circuits are connected to the BCM
through the JB/BCM connector. The BCM receives
ground through five separate circuits. Three of these
circuits are connected to the BCM through a connec-
tor and take out of the instrument panel wire har-
ness on three separate ground circuits, while the
other two circuits are connected to the BCM through
the JB/BCM connector. All of these circuits are
grounded through a splice block located in the instru-
ment panel wire harness with an eyelet terminal con-
nector that is secured by a nut to a ground stud on
the driver side instrument panel end bracket near
the JB.
The BCM monitors its own internal circuitry as
well as many of its input and output circuits, and
will store a Diagnostic Trouble Code (DTC) in elec-
tronic memory for any failure it detects. These DTCs
can be retrieved and diagnosed using a DRBIIItscan
tool. Refer to the appropriate diagnostic information.
HARD WIRED INPUTS The hard wired inputs to
the BCM include the following:
²A/C on/off control
²Ambient temperature sensor signal
²Body control module flash enable
²Door lock switch mux
²Driver door ajar switch sense
²Flip-up glass ajar switch sense
²Flip-up glass release switch sense
²Fog lamp switch sense
²Front wiper park switch sense
²Front wiper switch mux
²Front washer pump driver
²Fused B(+)
²Fused ignition switch output (run-acc)
²Fused ignition switch output (run-start)
²Headlamp switch mux
²High beam switch sense
²Hood ajar switch sense - premium with
VTSS - in markets where required only
²Key-in ignition switch sense
²Left cylinder lock switch sense - premium
with VTSS only - omitted in some markets as
required
²Panel lamps dimmer switch mux
²Passenger doors ajar switch sense (input
from three ajar switches connected in parallel)
²Radio control mux - premium with remote
radio switches only
²Rear courtesy lamp control
²Rear window defogger control
²Rear wiper intermittent driver
²Rear wiper on driver
²Right cylinder lock switch sense - premium
with VTSS only - omitted in some markets as
required
KJELECTRONIC CONTROL MODULES 8E - 5
BODY CONTROL MODULE (Continued)

²RKE antenna (two circuits) - premium with
RKE only
²Tailgate ajar switch sense
²Tailgate cylinder lock switch sense
²Vehicle speed sensor
Refer to the appropriate wiring information for
additional details.
HARD WIRED OUTPUTS The hard wired outputs
of the BCM include the following:
²Courtesy lamp driver
²Courtesy lamp load shed
²Door lock relay control
²Driver door unlock relay control - premium
with RKE only
²Flip-up glass release motor driver
²Front fog lamp relay control - premium
with front fog lamps only
²Front wiper high/low relay control
²Front wiper on/off relay control
²Hazard lamp control
²High beam relay control
²Horn relay control - premium with RKE
only
²Instrument cluster wake up signal
²Low beam relay control
²Park lamp relay control
²Passenger door unlock relay control
²Rear fog lamp relay control - premium with
rear fog lamps in markets where required only
²Rear window defogger relay control
²RKE supply - premium with RKE only
²Tailgate lock driver
²Tailgate unlock driver
²Vehicle speed output
²Vehicle speed sensor supply
²VTSS indicator driver - premium with
VTSS only
Refer to the appropriate wiring information for
additional details.
GROUNDS The BCM receives ground through five
separate circuits, and also supplies a ground path to
several switches through the following hard wired
circuits:
²Ambient temperature sensor return
²Door lock switch ground
²Headlamp switch return
²Radio control mux return
²RKE ground - premium with RKE only
²Tailgate switch ground
Refer to the appropriate wiring information for
additional details.
COMMUNICATION Not including the two RKE
antenna circuits (RKE antenna + and ±), which
merely pass through the premium BCM from the
RKE module to the external RKE antenna in theinstrument panel wire harness, the BCM has the fol-
lowing communication circuits:
²PCI bus
²RKE program serial data - premium with
RKE only
²RKE transmit serial data - premium with
RKE only
Refer to the appropriate wiring information for
additional details.
MESSAGING The BCM uses the following mes-
sages received from other electronic modules over the
PCI data bus:
²Battery Temperature (PCM)
²Compass Mini-Trip Computer Button Sta-
tus (CMTC) - premium only
²Coolant Temperature (PCM)
²Distance Pulses (PCM)
²Engine Speed (PCM)
²Fuel Tank Level (PCM)
²Fuel Used (PCM)
²Intrusion Transceiver Module Commands
(ITM) - premium in markets where required
only
²Manifold Absolute Pressure (PCM)
²OK to Lock - Rolling Locks (PCM)
²SKIS Status (SKIM)
²Vehicle Identification Number (PCM)
²Vehicle Speed (PCM)
The BCM provides the following messages to other
electronic modules over the PCI data bus:
²A/C Select Switch Status (PCM)
²Country Code (EMIC, PCM, CMTC)
²Distance to Empty (CMTC) - premium only
²Door Ajar Status (EMIC)
²Exterior Lighting Status (EMIC)
²Flip-up Glass Ajar Status (EMIC)
²Fuel Economy (Average and Instantaneous)
(CMTC) - premium only
²Hood Ajar Status (ITM) - premium in mar-
kets where required only
²Ignition On Timer (CMTC) - premium only
²Intrusion Transceiver Module Commands
(ITM) - premium in markets where required
only
²Key-In Ignition Switch Status (EMIC)
²Outside Temperature (CMTC) - premium
only
²Panel Lamp Intensity (CMTC, Radio)
²Tailgate Ajar Status (EMIC)
²Radio Mode (Radio) - premium only
²Radio Preset Scan (Radio) - premium only
²Radio Seek Down (Radio) - premium only
²Radio Seek Up (Radio) - premium only
²Radio Volume Down (Radio) - premium
only
²Radio Volume Up (Radio) - premium only
8E - 6 ELECTRONIC CONTROL MODULESKJ
BODY CONTROL MODULE (Continued)

²Vacuum Fluorescent Display Synchroniza-
tion (CMTC, EMIC, Radio)
²Vehicle Theft Security System Status (PCM,
ITM) - premium only
Refer to the appropriate diagnostic information for
additional details.
DIAGNOSIS AND TESTING - BODY CONTROL
MODULE
The hard wired inputs to and outputs from the
Body Control Module (BCM), as well as other hard
wired circuits for this module may be diagnosed and
tested using conventional diagnostic tools and proce-
dures. However, conventional diagnostic methods
may not prove conclusive in the diagnosis of the
BCM, the Programmable Communications Interface
(PCI) data bus network, or the electronic messages
received and transmitted by the BCM over the PCI
data bus. The most reliable, efficient, and accurate
means to diagnose the BCM and the PCI data bus
network inputs to and outputs from this module
requires the use of a DRBIIItscan tool. Refer to the
appropriate diagnostic information.
Refer to the appropriate wiring information. The
wiring information includes wiring diagrams, proper
wire and connector repair procedures, further details
on wire harness routing and retention, as well as
pin-out and location views for the various wire har-
ness connectors, splices and grounds.
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, DISABLE THE SUPPLEMENTAL RESTRAINT
SYSTEM BEFORE ATTEMPTING ANY STEERING
WHEEL, STEERING COLUMN, DRIVER AIRBAG,
PASSENGER AIRBAG, SEAT BELT TENSIONER,
FRONT IMPACT SENSORS, SIDE CURTAIN AIRBAG,
OR INSTRUMENT PANEL COMPONENT DIAGNOSIS
OR SERVICE. DISCONNECT AND ISOLATE THE
BATTERY NEGATIVE (GROUND) CABLE, THEN
WAIT TWO MINUTES FOR THE SYSTEM CAPACI-
TOR TO DISCHARGE BEFORE PERFORMING FUR-
THER DIAGNOSIS OR SERVICE. THIS IS THE ONLY
SURE WAY TO DISABLE THE SUPPLEMENTAL
RESTRAINT SYSTEM. FAILURE TO TAKE THE
PROPER PRECAUTIONS COULD RESULT IN ACCI-
DENTAL AIRBAG DEPLOYMENT AND POSSIBLE
PERSONAL INJURY.
REMOVAL
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, DISABLE THE SUPPLEMENTAL RESTRAINT
SYSTEM BEFORE ATTEMPTING ANY STEERING
WHEEL, STEERING COLUMN, DRIVER AIRBAG,
PASSENGER AIRBAG, SEAT BELT TENSIONER,FRONT IMPACT SENSORS, SIDE CURTAIN AIRBAG,
OR INSTRUMENT PANEL COMPONENT DIAGNOSIS
OR SERVICE. DISCONNECT AND ISOLATE THE
BATTERY NEGATIVE (GROUND) CABLE, THEN
WAIT TWO MINUTES FOR THE SYSTEM CAPACI-
TOR TO DISCHARGE BEFORE PERFORMING FUR-
THER DIAGNOSIS OR SERVICE. THIS IS THE ONLY
SURE WAY TO DISABLE THE SUPPLEMENTAL
RESTRAINT SYSTEM. FAILURE TO TAKE THE
PROPER PRECAUTIONS COULD RESULT IN ACCI-
DENTAL AIRBAG DEPLOYMENT AND POSSIBLE
PERSONAL INJURY.
NOTE: Before replacing a Body Control Module
(BCM), use a DRBIIITscan tool to retrieve the cur-
rent settings for the BCM programmable features
and the axle ratio/tire size (electronic pinion factor).
Refer to the appropriate diagnostic information.
These settings should be duplicated in the replace-
ment BCM using the DRBIIITscan tool before
returning the vehicle to service.
(1) Disconnect and isolate the battery negative
cable.
(2) Remove the Junction Block Module (JBM) from
the instrument panel end bracket on the driver side
of the vehicle. (Refer to 8 - ELECTRICAL/POWER
DISTRIBUTION/JUNCTION BLOCK - REMOVAL).
(3) Remove the four screws that secure the BCM
to the Junction Block (JB) (Fig. 3).
(4) Remove the BCM from the JB.
(5) If the vehicle is equipped with the optional
Remote Keyless Entry (RKE) system, remove the
RKE module from the receptacle on the BCM. (Refer
to 8 - ELECTRICAL/POWER LOCKS/REMOTE KEY-
LESS ENTRY MODULE - REMOVAL).
INSTALLATION
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, DISABLE THE SUPPLEMENTAL RESTRAINT
SYSTEM BEFORE ATTEMPTING ANY STEERING
WHEEL, STEERING COLUMN, DRIVER AIRBAG,
PASSENGER AIRBAG, SEAT BELT TENSIONER,
FRONT IMPACT SENSORS, SIDE CURTAIN AIRBAG,
OR INSTRUMENT PANEL COMPONENT DIAGNOSIS
OR SERVICE. DISCONNECT AND ISOLATE THE
BATTERY NEGATIVE (GROUND) CABLE, THEN
WAIT TWO MINUTES FOR THE SYSTEM CAPACI-
TOR TO DISCHARGE BEFORE PERFORMING FUR-
THER DIAGNOSIS OR SERVICE. THIS IS THE ONLY
SURE WAY TO DISABLE THE SUPPLEMENTAL
RESTRAINT SYSTEM. FAILURE TO TAKE THE
PROPER PRECAUTIONS COULD RESULT IN ACCI-
DENTAL AIRBAG DEPLOYMENT AND POSSIBLE
PERSONAL INJURY.
KJELECTRONIC CONTROL MODULES 8E - 7
BODY CONTROL MODULE (Continued)

NOTE: Before replacing a Body Control Module
(BCM), use a DRBIIITscan tool to retrieve the cur-
rent settings for the BCM programmable features
and the axle ratio/tire size (electronic pinion factor).
Refer to the appropriate diagnostic information.
These settings should be duplicated in the replace-
ment BCM using the DRBIIITscan tool before
returning the vehicle to service.
(1) If the vehicle is equipped with the optional
Remote Keyless Entry (RKE) system, reinstall the
RKE module into the receptacle on the BCM. (Refer
to 8 - ELECTRICAL/POWER LOCKS/REMOTE KEY-
LESS ENTRY MODULE - INSTALLATION).
(2) Position the BCM onto the Junction Block (JB)
(Fig. 3).
(3) Install and tighten the four screws that secure
the BCM to the JB. Tighten the screws to 2 N´m (18
in. lbs.).
(4) Reinstall the Junction Block Module (JBM)
onto the instrument panel end bracket on the driver
side of the vehicle. (Refer to 8 - ELECTRICAL/
POWER DISTRIBUTION/JUNCTION BLOCK -
INSTALLATION).
(5) Reconnect the battery negative cable.
COMMUNICATION
DESCRIPTION
The DaimlerChrysler Programmable Communica-
tion Interface (PCI) data bus system is a single wire
multiplex system used for vehicle communications on
many DaimlerChrysler Corporation vehicles. Multi-
plexing is a system that enables the transmission of
several messages over a single channel or circuit. All
DaimlerChrysler vehicles use this principle for com-
munication between various microprocessor-based
electronic control modules. The PCI data bus exceeds
the Society of Automotive Engineers (SAE) J1850
Standard for Class B Multiplexing.
Many of the electronic control modules in a vehicle
require information from the same sensing device. In
the past, if information from one sensing device was
required by several controllers, a wire from each con-
troller needed to be connected in parallel to that sen-
sor. In addition, each controller utilizing analog
sensors required an Analog/Digital (A/D) converter in
order to9read9these sensor inputs. Multiplexing
reduces wire harness complexity, sensor current
loads and controller hardware because each sensing
device is connected to only one controller, which
reads and distributes the sensor information to the
other controllers over the data bus. Also, because
each controller on the data bus can access the con-
troller sensor inputs to every other controller on the
data bus, more function and feature capabilities are
possible.
In addition to reducing wire harness complexity,
component sensor current loads and controller hard-
ware, multiplexing offers a diagnostic advantage. A
multiplex system allows the information flowing
between controllers to be monitored using a diagnos-
tic scan tool. The DaimlerChrysler system allows an
electronic control module to broadcast message data
out onto the bus where all other electronic control
modules can9hear9the messages that are being sent.
When a module hears a message on the data bus
that it requires, it relays that message to its micro-
processor. Each module ignores the messages on the
data bus that are being sent to other electronic con-
trol modules.
OPERATION
Data exchange between modules is achieved by
serial transmission of encoded data over a single wire
broadcast network. The wire colors used for the PCI
data bus circuits are yellow with a violet tracer, or
violet with a yellow tracer, depending upon the appli-
cation. The PCI data bus messages are carried over
the bus in the form of Variable Pulse Width Modu-
lated (VPWM) signals. The PCI data bus speed is an
average 10.4 Kilo-bits per second (Kbps). By compar-
Fig. 3 Body Control Module Remove/Install
1 - SCREW (4)
2 - RKE MODULE
3 - BODY CONTROL MODULE
4 - JUNCTION BLOCK
8E - 8 ELECTRONIC CONTROL MODULESKJ
BODY CONTROL MODULE (Continued)