2001 CHRYSLER VOYAGER airbag

this type of system would only refer to this circuit.
A faulty speaker could not cause this DTC.
3.2.1 REMOTE RADIO CONTROLS
These radios can be controlled via remote radio
switches (optional). These switches are located on
the back side of the steering wheel. They control
mode, preset, seek up, seek down, volume up and
volume down functions.
These functions are inputs to the Body Control
Module and can be read with the DRBIIItunder
ªbody computerº. The switches are a multiplexed
signal to the BCM. The radio control MUX circuit is
a 5 volt line that is pulled to ground through
different value resistors built into the switches.
This causes a voltage drop to be seen by the BCM
and it sends a specific message to the radio on the
PCI Bus circuit. The radio then responses to the
message.
This circuit is fairly simple to troubleshoot. The
circuit must be complete from the switches in the
steering wheel to the BCM. The ground must be
complete so that the switches can cause the voltage
drop for the BCM to see. The circuit passes through
the clockspring so continuity through this devise
must be verified.
3.2.2 CD CHANGER
The new in-dash CD Changer is designed to fit
into the existing cubby bin in the center stack. This
new cartridge-less CD Changer is controlled by
your radio, and allows you to individually load up to
four discs at a time. However, due to its compact
design, the CD Changer can only carry out one
operation at a time. For example, you can not load
a new disc while playing another at the same time.
Each operation happens sequentially.
The radio unit installed with your system pro-
vides control over all features of the CD Changer
with the exception of the CD load and eject func-
tions, which are controlled by buttons located on the
front of the CD Changer. The radio also supplies the
power, ground, PCI Bus, left and right speaker
output thru a single DIN cable. All features you
would expect, such as Disc Up/Down, Track Up/
Down, Random and Scan are controlled by the
radio, which also displays all relevant CD Changer
information on the radio display.
The CD Changer contains a Load/Eject button
and an indicator light for each of the four disc
positions. The individual light indicates whether a
CD is currently loaded in that particular chamber of
the CD Changer. Pressing the individual Load/Eject
button for a particular chamber will eject a disc
currently present in that chamber. If the chamber iscurrently empty, actuating the Load/Eject button
will position that chamber to receive and load a new
disc in that chamber.
3.3 BODY CONTROL MODULE
The body control module (BCM) supplies vehicle
occupants with visual and audible information and
controls various vehicle functions. To provide and
receive information, the module is interfaced to the
vehicle's serial bus communications network (PCI).
This network consists of the powertrain control
module (PCM), the engine control module (ECM) -
diesel only, the transmission control module (TCM),
the mechanical instrument cluster (MIC), the front
control module (FCM), the occupant restraint con-
troller (ORC), the compass/mini-trip (CMTC), the
electronic vehicle information center (EVIC), the
controller antilock brake (CAB), the HVAC control
module (ATC & MTC), the power sliding door (Left
& Right) modules (PSD), the power liftgate module
(PLG), the Audio system, the side impact airbag
control (left & right) modules (SIACM), the memory
seat/mirror module (MSMM), the RKE/thatcham
alarm module and the sentry key immobilizer mod-
ule (SKIM). The BCM is operational when battery
power is supplied to the module.
The body control module provides the following
features:
²Power Door Locks
²Automatic Door Lock
²Door Lock Inhibit
²Central Locking (with VTSS Only)
²Battery Protection
²The 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
²Compass/Minitrip Support
²Interior Lighting (Courtesy/Reading Lamps)
²BCM Diagnostic Reporting
²Electronic Liftgate Release (with Power Door
Locks)
²Exterior Lighting
²Power Folding Mirrors
²Remote Radio Controls
²Headlamp Time Delay (with/without Autohead-
lamps)
²Automatic Headlamps (with electrochromatic
mirror)
²Illuminated Entry
²Fade to Off
8
GENERAL INFORMATION

3.5 COMMUNICATION
The Programmable Communication Interface or
PCI Bus is a single wire multiplexed network capa-
ble of supporting binary encoded messages shared
between multiple modules. The PCI bus circuit is
identified as D25 and is white with a violet tracer.
Additional tracer colors may be added to the violet
in order to distinguish between different module
connections. The modules are wired in parallel.
Connections are made in the harness using splices.
One splice called the Diagnostic Junction Port,
serves as the ªHubº of the bus. The Diagnostic
Junction Port provides an access point to isolate
most of the modules on the bus in order to assist in
diagnosing the circuit. The following modules are
used on the RG:
²Body Control Module
²Front Control Module
²Occupant Restraint Controller
²Left Side Impact Airbag Control Module
²Right Side Impact Airbag Control Module
²Controller Antilock Brake
²Powertrain Control Module
²Engine Control Module - Diesel Only
²Radio
²CD Changer
²Transmission Control Module
²Automatic Temperature Control Module
²A/C Heater Control Module (MTC)
²Sentry Key Immobilizer Module
²RKE/Thatcham Alarm Module
²Memory Seat/Mirror Module
²Overhead Console
²Mechanical Instrument Cluster
²Left Sliding Door Control Module
²Right Sliding Door Control Module
²Power Liftgate Module
Each module provides its own bias and termina-
tion in order to transmit and receive messages. The
bus voltage is at zero volts when no modules are
transmitting and is pulled up to about seven and a
half volts when modules are transmitting.
The bus messages are transmitted at a rate
averaging 10800 bits per second. Since there is only
voltage present when the modules transmit and the
message length is only about 500 milliseconds, it is
ineffective to try and measure the bus activity witha conventional voltmeter. The preferred method is
to use the DRBIIItlab scope. The 12v square wave
selection on the 20-volt scale provides a good view of
the bus activity. Voltage on the bus should pulse
between zero and about seven and a half volts.
Refer to the following figure for some typical dis-
plays.
The PCI Bus failure modes are broken down into
two categories. Complete PCI Bus Communication
Failure and individual module no response. Causes
of complete PCI Bus Communication Failure in-
clude a short to ground or battery on the PCI
circuit. Individual module no response can be
caused by an open circuit at either the Diagnostic
Junction Port or the module, or an open battery or
ground circuit to the affected module.
Symptoms of a complete PCI Bus Communication
Failure would include but are not limited to:
²All gauges on the MIC stay at zero
²All telltales on MIC illuminate
²MIC backlighting at full intensity
²Dashed lines in the overhead console ambient
temperature display
²No response received from any module on the PCI
bus (except the PCM)
²No start (if equipped with Sentry Key Immobi-
lizer)
Symptoms of Individual module failure could
include any one or more of the above. The difference
would be that at least one or more modules would
respond to the DRBIIIt.
Diagnosis starts with symptom identification. If a
complete PCI Bus Communication Failure is sus-
pected, begin by identifying which modules the
vehicle is equipped with and then attempt to get a
response from the modules with the DRBIIIt.Ifany
modules are responding, the failure is not related to
the total bus, but can be caused by one or more
modules PCI circuit or power supply and ground
circuits. The DRBIIItmay display ªBUS +/- SIG-
NAL OPENº or ªNO RESPONSEº to indicate a
communication problem. These same messages will
be displayed if the vehicle is not equipped with that
particular module. The CCD error message is a
default message used by the DRBIIItand in no way
indicates whether or not the PCI bus is operational.
The message is only an indication that a module is
either not responding or the vehicle is not equipped.
11
GENERAL INFORMATION

3.7.6 EXTERIOR LIGHTING BATTERY
SAVER
The BCM monitors the status of, and controls, the
Park Lamps, Headlamps and Fog Lamp relays. If
any exterior lamps are left ON after the ignition is
turned OFF, the BCM will turn them OFF after 3
minutes.
3.7.7 AUTO HEADLAMPS
This feature is available on vehicles equipped
with both the Electrocromatic Mirror (ECM) and
the Compass/Mini-Trip Computer (CMTC). When
the BCM detects a day/night signal from the CMTC,
an ECM is present and Auto Headlamp mode is
selected.
3.8 FRONT CONTROL MODULE
The Front Control Module (FCM) is an electrical
control and interface center located in the engine
compartment. When it is mated to the Power Dis-
tribution Center (PDC), it is referred to as the
Intelligent Power Module (IPM). The IPM, with its
fuses and relays provides power and signal distri-
bution throughout most of the vehicle. The FCM
receives both hard wire and digital electronic inputs
from the vehicle electrical system through the PDC.
Based on these inputs and the ignition switch
position, it provides direct power feeds and relay
control to some of the vehicles' most critical electri-
cal systems.
The Front Control Module provides the following
features:
Controlled power feeds:
²Front airbag system
²Side airbag system
²Headlamp power
²EATX module power (4 speed only)
²Front washer motor
²Rear washer motor
²Brake shift interlock system
Relay controls:
²Fog lamp relay (when equipped)
²Park lamp relay
²Front wiper on relay
²Front wiper high/low relay
²Accessory relay
²Horn relay
²Front & rear blower relay
²Name brand speakers (NBS) relay
²Electronic back light (EBL) run only relay
²Cabin heater relayElectrical inputs:
²Headlamp battery supplies1&2
²Module battery supply
²Power ground
²Ignition switch RUN or START position status
²Ignition switch START only status
²PCI Bus
²Stop lamp switch
²Horn switch
²Back-up switch
²Wiper park switch
²Washer fluid level switch
²Brake fluid level switch
²Ambient temperature sensor
²Right park lamp outage
²Left park lamp outage
²Battery IOD
²Battery (+) connection detection
²Flash reprogramming voltage
3.8.1 CONTROLLED POWER FEEDS
Front airbag system
The FCM provides power to the Occupant Re-
straint Control (ORC) system through two ªfuse-
lessº circuits (ORC RUN/START, and ORC RUN
only). These circuits are electronically controlled
and continuously monitored for malfunctions.
Power is supplied while the ignition switch is in the
RUN and START positions on pin 48 of the FCM
connector, and in the RUN only position on pin 29.
Side airbag system
The FCM provides power to the Side Impact
Airbag Control Module (SIACM) system through
one ªfuselessº circuit. This circuit is electronically
controlled and continuously monitored for malfunc-
tions. Power is supplied in the ignition RUN and
START positions on pin 28 of the FCM connector.
Headlamp power
The headlamp switch is a direct input to the
BCM. The BCM sends a PCI Bus message to the
FCM informing it of a headlamp switch status
change. The FCM then turns on power to the
headlamps through four ªfuselessº circuits. These
circuits are electronically controlled and continu-
ously monitored for malfunctions. Power is supplied
to each filament in a separate circuit (RH low on pin
6, RH high on pin 4, LH low on pin 3 and LH high
on pin 5). For vehicles equipped with Daytime
Running Lamps (DRL), the FCM electronically
steps down the headlamp voltage to provide the
desired illumination.
13
GENERAL INFORMATION

WARNING: BEFORE ROAD TESTING A
VEHICLE, BE SURE THAT ALL
COMPONENTS ARE REASSEMBLED.
DURING THE TEST DRIVE, DO NOT TRY TO
READ THE DRBIIITSCREEN WHILE IN
MOTION. DO NOT HANG THE DRBIIITFROM
THE REAR VIEW MIRROR OR OPERATE IT
YOURSELF. HAVE AN ASSISTANT
AVAILABLE TO OPERATE THE DRBIIIT.
5.0 REQUIRED TOOLS AND
EQUIPMENT
DRBIIIt(diagnostic read-out box)
Jumper wires
Ohmmeter
Voltmeter
Sentry Key Tester
Test Light
8310 Airbag System Load Tool
8443 SRS Airbag System Load Tool
Diagnostic Junction Port Tester 8339
6.0 GLOSSARY OF TERMS
ABSantilock brake system
ACMairbag control module
AECMairbag electronic control module
(ACM)
ASDMairbag system diagnostic module
(ACM)
AT Cautomatic temperature control
BCMbody control module
CABcontroller antilock brake
CMTCcompass/mini-trip computer
CPAconnector positive assurance
DABdriver airbag
DCHAdiesel cabin heater assist
(cabin heater)
DLCdata link connector
DTCdiagnostic trouble code
DRdriver
EBLelectric back lite (rear window de-
fogger)ECMEngine control module
EVICelectronic vehicle information center
FCMfront control module
GCCGulf Coast Countries
HVACheater ventilation, air conditioning
IPMintelligent power module
LDUlower drive unit
LHDLeft Hand Drive
MICmechanical instrument cluster
MTCmanual temperature control
MSMMmemory seat/mirror module
OBDon board diagnostics
ODOodometer
ORCoccupant restraint controller
PA Bpassenger airbag
PASSpassenger
PCIProgrammable Communication In-
terface (vehicle communication bus)
PCMpowertrain control module
PDCpower distribution center
PLGpower liftgate
PLGMpower liftgate module
PSDpower sliding door
PSDMpower sliding door module
PWMpulse width modulated
RHDRight Hand Drive
RKEremote keyless entry
SABseat airbag
SBTseat belt tensioner
SIACMside impact airbag control module
SKIMsentry key immobilizer module
SKISsentry key immobilizer system
SQUIBalso called initiator (located inside
airbag)
SRSsupplemental restraint system
TCMtransmission control module
VFDvacuum fluorescent display
VTSSvehicle theft security system
30
GENERAL INFORMATION

Symptom List:
FCM, ORC RUN ONLY DRIVER OPEN - ACTIVE
FCM, ORC RUN ONLY DRIVER OVER CURRENT - ACTIVE
FCM, ORC RUN ONLY DRIVER OVER TEMP - ACTIVE
FCM, ORC RUN ONLY DRIVER OVER VOLT - ACTIVE
FCM, ORC RUN ONLY DRIVER SHORT TO GROUND - ACTIVE
ORC, LOSS OF IGNITION RUN ONLY - ACTIVE
Test Note: All symptoms listed above are diagnosed using the same tests.
The title for the tests will be FCM, ORC RUN ONLY DRIVER
OPEN - ACTIVE.
When Monitored and Set Condition:
FCM, ORC RUN ONLY DRIVER OPEN - ACTIVE
When Monitored: When the ignition is turned OFF, the microprocessor controlled
transistor (high side driver) places a diagnostic voltage on the ORC Run-Start circuit for
60 seconds. An open high side driver (HSD) circuit voltage is between 2.4 and 5.0 volts.
Set Condition: This code will set within 10 second, if the microprocessor senses 2.4 to 5.0
volts on the HSD. Note: the diagnostic voltage will only last for 60 seconds after the
ignition is turned off.
FCM, ORC RUN ONLY DRIVER OVER CURRENT - ACTIVE
When Monitored: The FCM uses a microprocessor controlled transistor (high side driver)
to supply power to the ORC. The microprocessor monitors the high side driver (HSD)
internal temperature when the ignition is in the Run Only position.
Set Condition: The code will set within 1 second, if the microprocessor senses HSD
internal temperature. The high temperature is caused by over current.
FCM, ORC RUN ONLY DRIVER OVER TEMP - ACTIVE
When Monitored: The FCM uses a microprocessor controlled transistor (high side driver)
to supply power to the ORC. The microprocessor monitors the high side driver (HSD)
internal temperature when the ignition is in the Run position.
Set Condition: The code will set within 2.5 second, if the microprocessor senses high HSD
internal temperature. The high temperature is caused by over current.
FCM, ORC RUN ONLY DRIVER OVER VOLT - ACTIVE
When Monitored: The FCM uses a microprocessor controlled transistor (high side driver)
to supply power to the ORC. The microprocessor monitors the high side driver (HSD)
battery voltage when the ignition is in the run position.
Set Condition: The code will set if the microprocessor senses HSD battery voltage is over
30 volts.
32
AIRBAG

FCM, ORC RUN ONLY DRIVER SHORT TO GROUND - ACTIVE
When Monitored: When the ignition is turned OFF, the microprocessor controlled
transistor (high side driver) places a diagnostic voltage on the ORC Run-Start circuit for
60 seconds. An open high side driver (HSD) circuit voltage is between 2.4 and 5.0 volts.
Set Condition: This code will set within 10 second, if the microprocessor senses 2.4 to 5.0
volts on the HSD. Note: the diagnostic voltage will only last for 60 seconds after the
ignition is turned off.
ORC, LOSS OF IGNITION RUN ONLY - ACTIVE
When Monitored: With the ignition in the run only position the ORC monitors the ORC
Run Only Driver circuit for proper system voltage.
Set Condition: If the voltage on the ORC Run Only Driver circuit drops below 4.5 volts,
the code will set.
POSSIBLE CAUSES
VERIFYING ORC RUN ONLY DRIVER CODES
CHECK BATTERY VOLTAGE
FCM, RUN ONLY DRIVER OVER VOLTAGE
ORC, RUN ONLY OPEN TEST
FCM, RUN ONLY OPEN TEST
IPM, RUN ONLY OPEN TEST
ORC RUN ONLY DRIVER CIRCUIT OPEN
FCM, RUN ONLY SHORT TEST
IPM, RUN ONLY SHORT TEST
ORC RUN ONLY DRIVER CIRCUIT SHORT
33
AIRBAG
FCM, ORC RUN ONLY DRIVER OPEN - ACTIVE ÐContinued

TEST ACTION APPLICABILITY
1 Ensure that the battery is fully charged.
WARNING: TURN THE IGNITION OFF, DISCONNECT THE BATTERY AND
WAIT TWO MINUTES BEFORE PROCEEDING.
WARNING: IF THE OCCUPANT RESTRAINT CONTROLLER IS DROPPED
AT ANY TIME, IT MUST BE REPLACED.
Disconnect the Occupant Restraint Controller Connector.
NOTE: Check connectors - Clean and repair as necessary.
WARNING: TURN IGNITION ON, THEN RECONNECT THE BATTERY.
With the DRBIIIt, read the active FCM DTCs.
Turn the ignition off.
With the DRBIIIt, read the active FCM DTCs.
NOTE: The ORC RUN ONLY DRIVER OPEN code may not set until the
ignition key is turned off.
Select the active FCM DTC that was displayed on the DRB.All
1. ORC RUN ONLY DRIVER OPEN
Go To 2
2. ORC RUN ONLY DRIVER OVER VOLTAGE
Go To 5
3. ORC RUN ONLY SHORT TO GROUND
Go To 6
4. ORC RUN ONLY DRIVER OVER CURRENT
Go To 6
5. ORC RUN ONLY DRIVER OVER TEMP
Go To 6
6. None of the above.
Replace the Front Control Module.
Perform BODY VERIFICATION TEST - VER 1.
NOTE: When reconnecting airbag system components the Ignition must be
turned off and the Battery must be disconnected.
2WARNING: TURN THE IGNITION OFF, DISCONNECT THE BATTERY AND
WAIT TWO MINUTES BEFORE PROCEEDING.
WARNING: IF THE OCCUPANT RESTRAINT CONTROLLER IS DROPPED
AT ANY TIME, IT MUST BE REPLACED.
Disconnect the Occupant Restraint Controller.
TURN THE IGNITION ON, THEN RECONNECT THE BATTERY.
Connect a test light to ground and the ORC Run Only Driver circuit at the Occupant
Restraint Controller connector.
Cycle the ignition switch from ON to OFF.
With the DRBIIIt, read the active FCM DTCs.
Does the DRB show an active ORC RUN ONLY DRIVER OPEN code?All
Ye s®Go To 3
No®Replace the Occupant Restraint Controller in accordance with
Service Instructions. WARNING: make sure the battery is discon-
nected and wait 2 minutes before proceeding.
Perform AIRBAG VERIFICATION TEST - VER 1.
NOTE: When reconnecting airbag system components the Ignition must be
turned off and the Battery must be disconnected.
34
AIRBAG
FCM, ORC RUN ONLY DRIVER OPEN - ACTIVE ÐContinued

TEST ACTION APPLICABILITY
3 Disconnect the Front Control Module.
NOTE: Check connectors - Clean and repair as necessary.
Measure the resistance of the ORC Run Only Driver circuit between the Front
Control Module connector and the Occupant Restraint Controller connector.
Is the resistance below 1.0 ohms ?All
Ye s®Replace the Front Control Module.
Perform AIRBAG VERIFICATION TEST - VER 1.
No®Go To 4
NOTE: When reconnecting airbag system components the Ignition must be
turned off and the Battery must be disconnected.
4 Gain access to the connectors on the bottom of the IPM.
Disconnect the IPM C7 connector.
NOTE: Check connectors - Clean/repair as necessary.
Measure the resistance of the ORC Run Only Driver circuit between the IPM C7
connector and the Occupant Restraint Controller connector.
Is the resistance below 1.0 ohms ?All
Ye s®Replace the IPM.
Perform AIRBAG VERIFICATION TEST - VER 1.
No®Repair the open ORC Run Only Driver circuit.
Perform AIRBAG VERIFICATION TEST - VER 1.
NOTE: When reconnecting airbag system components the Ignition must be
turned off and the Battery must be disconnected.
5 Measure the battery voltage.
Is the voltage above 30.0 volts?All
Ye s®Refer to Charging Category for the P1594 Charging System Too
High symptom.
Perform AIRBAG VERIFICATION TEST - VER 1.
No®Replace the Front Control Module.
Perform AIRBAG VERIFICATION TEST - VER 1.
6WARNING: TURN IGNITION OFF, DISCONNECT THE BATTERY AND WAIT
TWO MINUTES BEFORE PROCEEDING.
Disconnect Occupant Restraints Controller.
NOTE: Check connectors - Clean and repair as necessary.
Measure the resistance of the ORC Run Only Driver circuit between the Front
Control Module connector and ground.
Is the resistance below 500.0 Kohms?All
Ye s®Go To 7
No®Replace the Front Control Module.
Perform AIRBAG VERIFICATION TEST - VER 1.
NOTE: When reconnecting airbag system components the Ignition must be
turned off and the Battery must be disconnected.
35
AIRBAG
FCM, ORC RUN ONLY DRIVER OPEN - ACTIVE ÐContinued