instrument panel DODGE RAM 2003 Service Owner's Manual

appropriate wiring information. The wiring informa-
tion includes wiring diagrams, proper wire and con-
nector repair procedures, details of wire harness
routing and retention, connector pin-out information
and location views for the various wire harness con-
nectors, splices and grounds.
DIAGNOSIS AND TESTING - SPEAKER
Any diagnosis of the Audio system should
begin with the use of the DRB IIItdiagnostic
tool. For information on the use of the DRB
IIIt, refer to the appropriate Diagnostic Service
Manual.
Refer to the appropriate wiring information. The
wiring information includes wiring diagrams, proper
wire and connector repair procedures, details of wire
harness routing and retention, connector pin-out
information and location views for the various wire
harness connectors, splices and grounds.
WARNING: DISABLE THE AIRBAG SYSTEM
BEFORE ATTEMPTING ANY STEERING WHEEL,
STEERING COLUMN, SEAT BELT TENSIONER, SIDE
AIRBAG, OR INSTRUMENT PANEL COMPONENT
DIAGNOSIS OR SERVICE. DISCONNECT AND ISO-
LATE THE BATTERY NEGATIVE (GROUND) CABLE,
THEN WAIT TWO MINUTES FOR THE AIRBAG SYS-
TEM CAPACITOR TO DISCHARGE BEFORE PER-
FORMING FURTHER DIAGNOSIS OR SERVICE. THIS
IS THE ONLY SURE WAY TO DISABLE THE AIRBAG
SYSTEM. FAILURE TO TAKE THE PROPER PRE-
CAUTIONS COULD RESULT IN ACCIDENTAL AIR-
BAG DEPLOYMENT AND POSSIBLE PERSONAL
INJURY.
CAUTION: The speaker output of the radio is a
ªfloating groundº system. Do not allow any speaker
lead to short to ground, as damage to the radio
and/or amplifier may result.
(1) If all speakers are inoperative, check the fuses
in the Integrated Power Module (IPM). If OK, go to
Step 2. If not OK, repair the shorted circuit or com-
ponent as required and replace the faulty fuse.
(2) Check the amplifier fuse (if equipped) in the
IPM. If OK, go to Step 3. If not OK, repair the
shorted circuit or component as required and replace
the faulty fuse.
(3) Turn the ignition switch to the ON position.
Turn the radio receiver ON. Adjust the balance and
fader control controls to check the performance of
each individual speaker. Note the speaker locations
that are not performing correctly. Go to Step 4.
(4) Turn the radio receiver OFF. Turn the ignition
OFF. Disconnect and isolate the battery negativecable. If vehicle isnotequipped with a amplifier,
remove the radio receiver. If vehicle is equipped with
an amplifier. disconnect wire harness connector at
output side of amplifier. Go to Step 5.
(5) Check both the speaker feed (+) circuit and
return (-) circuit cavities for the inoperative speaker
at the radio receiver wire harness connector for con-
tinuity to ground. There should be no continuity. If
OK, go to Step 6. If not OK, repair the shorted
speaker feed (+) and/or return (-) circuits(s) to the
speaker as required.
(6) Disconnect wire harness connector at the inop-
erative speaker. Check for continuity between the
speaker feed (+) circuit cavities of the radio receiver
wire harness connector or if equipped, the amplifier
wire harness connector and the speaker wire harness
connector. Repeat the check between the speaker
return (-) circuit cavities of the radio receiver wire
harness connector and the speaker wire harness con-
nector. In each case, there should be continuity. If
OK, replace the faulty speaker. If not OK, repair the
open speaker feed (+) and/or return (-) circuits(s) as
required.
REMOVAL
FRONT DOOR SPEAKER
(1) Disconnect and isolate the battery negative
cable.
(2) Remove front door trim panel (Refer to 23 -
BODY/DOOR - FRONT/TRIM PANEL - REMOVAL).
(3) Remove speaker mounting screws (Fig. 16).
(4) Disconnect electrical harness connector and
remove speaker.
Fig. 16 FRONT DOOR SPEAKER
DRAUDIO 8A - 13
SPEAKER (Continued)

INSTRUMENT PANEL CENTER SPEAKER
(1) Disconnect and isolate the battery negative
cable.
(2) Remove instrument panel top cover (Refer to
23 - BODY/INSTRUMENT PANEL/INSTRUMENT
PANEL TOP COVER - REMOVAL).
(3) Remove speaker mounting screws (Fig. 17).
(4) Disconnect electrical harness connector and
remove speaker.
INSTRUMENT PANEL END SPEAKER
(1) Disconnect and isolate the battery negative
cable.
(2) Remove instrument panel top cover (Refer to
23 - BODY/INSTRUMENT PANEL/INSTRUMENT
PANEL TOP COVER - REMOVAL).
(3) Remove speaker mounting screws (Fig. 18)
(4) Disconnect electrical harness connector and
remove speaker.
REAR CAB SIDE SPEAKER
(1) Disconnect and isolate the battery negative
cable.
(2) Remove B-pillar lower trim (Refer to 23 -
BODY/INTERIOR/B-PILLAR LOWER TRIM -
REMOVAL).
(3) Remove speaker mounting screws (Fig. 19).
(4) Disconnect electrical harness connector and
remove speaker.
REAR DOOR SPEAKER
(1) Disconnect and isolate the battery negative
cable.
(2) Remove rear door trim panel (Refer to 23 -
BODY/DOORS - REAR/TRIM PANEL - REMOVAL).
(3) Remove speaker mounting screws (Fig. 20).
(4) Disconnect electrical harness connector and
remove speaker.
Fig. 17 INSTRUMENT PANEL CENTER SPEAKER
Fig. 18 INSTRUMENT PANEL END SPEAKER
Fig. 19 REAR CAB SIDE SPEAKER
Fig. 20 REAR DOOR SPEAKER
8A - 14 AUDIODR
SPEAKER (Continued)

INSTALLATION
FRONT DOOR SPEAKER
(1) Connect electrical harness connector and
install speaker.
(2) Install front door trim panel (Refer to 23 -
BODY/DOOR - FRONT/TRIM PANEL - INSTALLA-
TION).
(3) Connect battery negative cable.
INSTRUMENT PANEL CENTER SPEAKER
(1) Connect electrical harness connector and
install speaker.
(2) Install instrument panel top cover (Refer to 23
- BODY/INSTRUMENT PANEL/INSTRUMENT
PANEL TOP COVER - INSTALLATION).
(3) Connect battery negative cable.
INSTRUMENT PANEL END SPEAKER
(1) Connect electrical harness connector and
install speaker.(2) Install instrument panel top cover (Refer to 23
- BODY/INSTRUMENT PANEL/INSTRUMENT
PANEL TOP COVER - INSTALLATION).
(3) Connect battery negative cable.
REAR CAB SIDE SPEAKER
(1) Connect electrical harness connector and
install speaker.
(2) Install B-pillar lower trim (Refer to 23 - BODY/
INTERIOR/B-PILLAR LOWER TRIM - INSTALLA-
TION).
(3) Connect battery negative cable.
REAR DOOR SPEAKER
(1) Connect electrical harness connector and
install speaker.
(2) Install rear door trim panel (Refer to 23 -
BODY/DOORS - REAR/TRIM PANEL - INSTALLA-
TION).
(3) Connect battery negative cable.
DRAUDIO 8A - 15
SPEAKER (Continued)

²Cyclic Redundancy Check (CRC) Byte- This
byte is used to detect errors during a message trans-
mission.
²In-Frame Response (IFR) byte(s)-Ifa
response is required from the target module(s), it can
be sent during this frame. This function is described
in greater detail in the following paragraph.
The IFR consists of one or more bytes, which are
transmitted during a message. If the sending module
requires information to be received immediately, the
target module(s) can send data over the bus during
the original message. This allows the sending module
to receive time-critical information without having to
wait for the target module to access the bus. After
the IFR is received, the sending module broadcasts
an End of Frame (EOF) message and releases control
of the bus.
The PCI data bus can be monitored using the
DRBIIItscan tool. It is possible, however, for the bus
to pass all DRBIIIttests and still be faulty if the
voltage parameters are all within the specified range
and false messages are being sent.
CONTROLLER ANTILOCK
BRAKE
DESCRIPTION
The Controler Antilock Brake (CAB) is mounted to
the Hydraulic Control Unit (HCU) and operates the
ABS system (Fig. 1).
OPERATION
The CAB voltage source is through the ignition
switch in the RUN position. The CAB contains a self
check program that illuminates the ABS warning
light when a system fault is detected. Faults are
stored in a diagnostic program memory and are
accessible with the DRB III scan tool. ABS faults
remain in memory until cleared, or until after the
vehicle is started approximately 50 times. Stored
faults arenoterased if the battery is disconnected.
NOTE: If the CAB is being replaced with a new CAB
is must be reprogrammed with the use of a DRB III.
REMOVAL
(1) Remove the negative battery cable from the
battery.
(2) Pull up on the CAB harness connector release
and remove connector.
(3) Remove the CAB mounting bolts.
(4) Remove the pump connector from the CAB.
(5) Remove the CAB from the HCU.
INSTALLATION
NOTE: If the CAB is being replaced with a new CAB
is must be reprogrammed with the use of a DRB III.
(1) Install CAB to the HCU.
(2) Install the pump connector to the CAB.
(3) Install mounting bolts. Tighten to 2 N´m (16 in.
lbs.).
(4) Install the wiring harness connector to the
CAB and push down on the release to secure the con-
nector.
(5) Install negative battery cable to the battery.
DATA LINK CONNECTOR
DESCRIPTION - DATA LINK CONNECTOR
The Data Link Connector (DLC) is located at the
lower edge of the instrument panel near the steering
column.
OPERATION - DATA LINK CONNECTOR
The 16±way data link connector (diagnostic scan
tool connector) links the Diagnostic Readout Box
(DRB) scan tool or the Mopar Diagnostic System
(MDS) with the Powertrain Control Module (PCM).
Fig. 1 HYDRAULIC CONTROL UNIT
1 - HYDRAULIC CONTROL UNIT
2 - MOUNTING BOLTS
DRELECTRONIC CONTROL MODULES 8E - 3
COMMUNICATION (Continued)

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) If ignition key programming is unsuccessful,
the DRBIIItscan tool will display one of the follow-
ing messages:
(a) Programming Not Attempted - The DRBIIIt
scan tool attempts to read the programmed key
status and there are no keys programmed into
SKIM memory.
(b) 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.
(c) 8 Keys Already Learned, Programming Not
Done - SKIM transponder ID memory is full.
(6) Obtain ignition keys to be programmed from
customer (8 keys maximum).
(7) Using the DRBIIItscan tool, erase all ignition
keys by selecting MISCELLANEOUS and ERASE
ALL CURRENT IGN. KEYS.
(8) Program all ignition keys.
Learned Key In Ignition - Ignition key transponder
ID is currently programmed in SKIM memory.
REMOVAL
(1) Disconnect and isolate the battery negative
cable.
(2) Remove the steering column upper and lower
shrouds. Refer to Steering, Column, Shroud,
Removal.
(3) Disconnect the steering column wire harness
connector from the Sentry Key Immobilizer Module
(SKIM)
(4) Remove the screw securing the SKIM module
to the steering column (Fig. 8).
(5) Release the SKIM antenna ring retaining clips
from around the ignition switch lock cylinder housing
and remove the SKIM.
INSTALLATION
NOTE: If the SKIM is replaced with a new unit, a
DRBIIITscan tool MUST be used to initialize the
new SKIM and to program at least two Sentry Key
transponders. (Refer to 8 - ELECTRICAL/VEHICLE
THEFT SECURITY - STANDARD PROCEDURE).
(1) Slide the SKIM antenna ring around the igni-
tion switch lock cylinder housing and clip in place
(Fig. 8).
(2) Install the retaining screw.
(3) Connect the steering column wire harness con-
nector to the Sentry Key Immobilizer Module
(SKIM).(4) Install the steering column upper and lower
shrouds. Refer to Steering, Column, Shroud, Installa-
tion.
(5) Connect the battery negative cable.
TRANSFER CASE CONTROL
MODULE
DESCRIPTION
The Transfer Case Control Module (TCCM) (Fig. 9)
is a microprocessor-based assembly, controlling the
4X4 transfer case shift functions via the actuation of
a shift motor and utilizing the feedback of a mode
sensor assembly. Communication is via the PCI serial
bus. Inputs include user selectable 4X4 modes that
include 2WD, 4HI, 4LO, and Neutral. The logic and
driver circuitry is contained in a molded plastic hous-
ing with an embedded heat-sink and is located
behind the left side of the lower instrument panel.
OPERATION
The Transfer Case Control Module (TCCM) utilizes
the input from the transfer case mounted mode sen-
sor, the instrument panel mounted selector switch,
and the following information from the vehicle's PCI
serial bus to determine if a shift is allowed.
²Engine RPM and Vehicle Speed
Fig. 8 SENTRY KEY IMMOBILIZER MODULE (SKIM)
1 - SENTRY KEY IMMOBILIZER MODULE (SKIM)
2 - STEERING COLUMN
3 - SCREW
4 - WIRING HARNES
DRELECTRONIC CONTROL MODULES 8E - 15
SENTRY KEY IMMOBILIZER MODULE (Continued)

²Diagnostic Requests
²Manual Transmission and Brake Applied
²PRNDL
²Ignition Status
²ABS Messages
Once the TCCM determines that a requested shift
is allowed, it actuates the bi-directional shift motor
as necessary to achieve the desired transfer case
operating mode. The TCCM also monitors the mode
sensor while controlling the shift motor to determine
the status of the shift attempt.
Several items can cause the requested shift not to
be completed. If the TCCM has recognized a fault
(DTC) of some variety, it will begin operation in one
of four Functionality Levels. These levels are:
²Level Zero- Normal Operation.
²Level One- Only Mode Shifts Are Allowed.
²Level Two- Only Mode Shifts and Shifts Into
LOW Are Allowed (No Neutral Shifts Are Allowed).
²Level Three- No Shifts Are Allowed
The TCCM can also be operating in one of three
possible power modes. These power modes are:
²Full Power Modeis the normal operational
mode of the module. This mode is achieved by normal
PCI bus traffic being present and the ignition being
in the RUN position.
²Reduced Power Modewill be entered when
the ignition has been powered off. In this state, the
module will shut down power supplied to external
devices, and to electronic interface inputs and out-
puts. From this state the module can enter either
Sleep Mode or Full Power Mode. To enter this mode,
the module must receive an ignition message denot-
ing that the ignition is off, or not receive any mes-
sages for 5  0.5 seconds. To exit this mode, themodule must receive one ignition message that
denotes that the ignition is in the RUN position.
²Sleep Modewill be entered, from the Reduced
Power Mode, when no PCI traffic has been sensed for
20  1 seconds. If during Sleep Mode the module
detects PCI bus traffic, it will revert to the Reduced
Power mode while monitoring for ignition messages.
It will remain in this state as long as there is traffic
other than run or start messages, and will return to
Sleep mode if the bus goes without traffic for 20  1
seconds.
SHIFT REQUIREMENTS
If the TCCM is in full power mode and at function-
ality level zero, it uses the following criteria to deter-
mine if a shift is allowed.
If any of the driver controllable conditions are not
met once the shift request is recognized, the TCCM
will solidly illuminate the source position's LED and
flash the desired position's LED for all shifts except
NEUTRAL. The NEUTRAL shift LED strategy will
be discussed later.
Mode shiftswill be allowed regardless of trans-
mission gear or vehicle speed, whenever the following
conditions are met:
²Front and rear wheel speed are within 21 km/hr
(13 mph).
²A change in the Selector switch state indicates
that a mode shift has been requested.
²A valid mode sensor signal is being sensed by
the TCCM.
²Proper transmit/receive messages are occurring
on the PCI bus.
²Ignition key switch is in the RUN position.
Range shiftswill be allowed only if all of the fol-
lowing conditions are met:
²Front and rear wheel speed are within 21 km/hr
(13 mph).
²A change in the Selector Switch state indicating
a range shift has been requested.
²Transmission in NEUTRAL signal must be rec-
ognized for at least 1.5 seconds  100 msec. (Automat-
ic transmissions only)
²Proper transmit/receive messages are occurring
on the PCI bus.
²Clutch signal is recognized for 500 msec   50
msec (Manual transmissions only).
²Vehicle speed is less than or equal to 4.8 km/hr
(3 miles per hour).
²Ignition key switch is in the RUN position.
²A valid mode sensor signal is being sensed by
the TCCM.
Ashift into transfer case Neutralwill be
allowed only if all of the following conditions are met:
²Front and rear wheel speed are within 21 km/hr
(13 mph).
Fig. 9 Transfer Case Control Module (TCCM)
Location
1 - INSTRUMENT PANEL
2 - TRANSFER CASE CONTROL MODULE (TCCM)
3 - TRANSFER CASE SELECTOR SWITCH
8E - 16 ELECTRONIC CONTROL MODULESDR
TRANSFER CASE CONTROL MODULE (Continued)

CHARGING
TABLE OF CONTENTS
page page
CHARGING
DESCRIPTION.........................19
OPERATION...........................19
DIAGNOSIS AND TESTING - CHARGING
SYSTEM............................19
SPECIFICATIONS
GENERATOR RATINGS.................20
SPECIFICATIONS - TORQUE - GENERATOR
/ CHARGING SYSTEM..................20
BATTERY TEMPERATURE SENSOR
DESCRIPTION.........................21OPERATION...........................21
REMOVAL.............................21
INSTALLATION.........................21
GENERATOR
DESCRIPTION.........................22
OPERATION...........................22
REMOVAL.............................22
INSTALLATION.........................25
VOLTAGE REGULATOR
DESCRIPTION.........................27
OPERATION...........................27
CHARGING
DESCRIPTION
The charging system consists of:
²Generator
²Electronic Voltage Regulator (EVR) circuitry
within the Powertrain Control Module (PCM). Elec-
tronic Control Module (ECM) for diesel engines.
²Ignition switch
²Battery (refer to 8, Battery for information)
²Battery temperature sensor
²Check Gauges Lamp (if equipped)
²Voltmeter (refer to 8, Instrument Panel and
Gauges for information)
²Wiring harness and connections (refer to 8, Wir-
ing Diagrams for information)
OPERATION
The charging system is turned on and off with the
ignition switch. The system is on when the engine is
running and the ASD relay is energized. When the
ASD relay is on, voltage is supplied to the ASD relay
sense circuit at the PCM (ECM Diesel). This voltage
is connected through the PCM (ECM Diesel) and sup-
plied to one of the generator field terminals (Gen.
Source +) at the back of the generator.
The amount of direct current produced by the gen-
erator is controlled by the EVR (field control) cir-
cuitry contained within the PCM (ECM Diesel). This
circuitry is connected in series with the second rotor
field terminal and ground.
A battery temperature sensor, located in the bat-
tery tray housing, is used to sense battery tempera-
ture. This temperature data, along with data from
monitored line voltage, is used by the PCM (ECM
Diesel) to vary the battery charging rate. This isdone by cycling the ground path to control the
strength of the rotor magnetic field. The PCM then
compensates and regulates generator current output
accordingly.
All vehicles are equipped with On-Board Diagnos-
tics (OBD). All OBD-sensed systems, including EVR
(field control) circuitry, are monitored by the PCM
(ECM Diesel). Each monitored circuit is assigned a
Diagnostic Trouble Code (DTC). The PCM will store a
DTC in electronic memory for certain failures it
detects.
The Check Gauges Lamp (if equipped) monitors:
charging system voltage,engine coolant tempera-
ture and engine oil pressure. If an extreme condition
is indicated, the lamp will be illuminated. This is
done as reminder to check the three gauges. The sig-
nal to activate the lamp is sent via the CCD bus cir-
cuits. The lamp is located on the instrument panel.
Refer to 8, Instrument Panel and Gauges for addi-
tional information.
DIAGNOSIS AND TESTING - CHARGING
SYSTEM
The following procedures may be used to diagnose
the charging system if:
²the check gauges lamp (if equipped) is illumi-
nated with the engine running
²the voltmeter (if equipped) does not register
properly
²an undercharged or overcharged battery condi-
tion occurs.
Remember that an undercharged battery is often
caused by:
²accessories being left on with the engine not
running
DRCHARGING 8F - 19

Starting System Diagnosis
CONDITION POSSIBLE CAUSE CORRECTION
STARTER ENGAGES,
SPINS OUT BEFORE
ENGINE STARTS.1. Starter ring gear faulty. 1. Refer to Starter Motor Removal and Installation.
Remove starter motor to inspect starter ring gear.
Replace starter ring gear if required.
2. Starter motor faulty. 2. If all other starting system components and circuits test
OK, replace starter motor assembly.
STARTER DOES NOT
DISENGAGE.1. Starter motor
improperly installed.1. Refer to Starter Motor Removal and Installation.
Tighten starter mounting hardware to correct torque
specifications.
2. Starter relay faulty. 2. Refer to Starter Relay Diagnosis and Testing. Replace
starter relay if required.
3. Ignition switch faulty. 3. Refer to Ignition Switch and Key Lock Cylinder.
Replace ignition switch if required.
4. Starter motor faulty. 4. If all other starting system components and circuits test
OK, replace starter motor.
INSPECTION
For complete starter wiring circuit diagrams, refer
to 8, Wiring Diagrams. Before removing any unit
from starting system for repair or diagnosis, perform
the following inspections:
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, REFER TO 8, PASSIVE RESTRAINT SYS-
TEMS, BEFORE ATTEMPTING ANY STEERING
WHEEL, STEERING COLUMN, OR INSTRUMENT
PANEL COMPONENT DIAGNOSIS OR SERVICE.
FAILURE TO TAKE THE PROPER PRECAUTIONS
COULD RESULT IN ACCIDENTAL AIRBAG DEPLOY-
MENT AND POSSIBLE PERSONAL INJURY.
²Battery- Visually inspect battery for indica-
tions of physical damage and loose or corroded cable
connections. Determine state-of-charge and cranking
capacity of battery. Charge or replace battery if
required. Refer toBatteryin 8, Battery.Note: If
equipped with diesel engine, a dual battery sys-
tem may be used, and both batteries must be
inspected.
²Ignition Switch- Visually inspect ignition
switch for indications of physical damage and loose
or corroded wire harness connections. Refer toIgni-
tion Switch and Key Lock Cylinder.
²Clutch Pedal Position Switch- If equipped
with manual transmission, visually inspect clutch
pedal position switch for indications of physical dam-
age and loose or corroded wire harness connections.
Refer toClutch Pedal Position Switchin 6,
Clutch.
²Park/Neutral Position Switch- If equipped
with automatic transmission, visually inspect park/
neutral position switch for indications of physical
damage and loose or corroded wire harness connec-tions. Refer toPark/Neutral Position Switchin
21, Transmission.
²Starter Relay- Visually inspect starter relay
for indications of physical damage and loose or cor-
roded wire harness connections.
²Starter Motor- Visually inspect starter motor
for indications of physical damage and loose or cor-
roded wire harness connections.
²Starter Solenoid- Visually inspect starter sole-
noid for indications of physical damage and loose or
corroded wire harness connections.
²Wiring- Visually inspect wire harnesses for
damage. Repair or replace any faulty wiring, as
required. Refer to 8, Wiring Diagrams.
TESTING
COLD CRANKING TEST
For complete starter wiring circuit diagrams, refer
to 8, Wiring Diagrams. The battery must be fully-
charged and load-tested before proceeding. Refer to
Batteryin 8, Battery.
(1) Connect volt-ampere tester to battery terminals
(Fig. 1). See instructions provided by manufacturer of
volt-ampere tester being used.Note: Certain diesel
equipped models use dual batteries. If equipped
with dual battery system, tester should be con-
nected to battery on left side of vehicle only.
Also, tester current reading must be taken from
positive battery cable lead that connects to
starter motor.
(2) Fully engage parking brake.
(3) If equipped with manual transmission, place
gearshift selector lever in Neutral position and block
clutch pedal in fully depressed position. If equipped
8F - 30 STARTINGDR
STARTING (Continued)

HEATED SYSTEMS
TABLE OF CONTENTS
page page
HEATED MIRRORS......................... 1 HEATED SEATSYSTEM..................... 3
HEATED MIRRORS
TABLE OF CONTENTS
page page
HEATED MIRRORS
DESCRIPTION - HEATED MIRROR SYSTEM . . . 1
OPERATION - HEATED MIRROR SYSTEM.....1DIAGNOSIS AND TESTING - HEATED
MIRROR SYSTEM......................2
HEATED MIRRORS
DESCRIPTION - HEATED MIRROR SYSTEM
Electrically heated outside rear view mirrors are
an additional factory-installed option on models that
are equipped with factory-installed dual power mir-
rors. Vehicles with this option can be visually identi-
fied by the International Control and Display Symbol
icon for rear window defogger, which appears on thelower inboard corner of each outside mirror glass
(Fig. 1); or, by the heated mirror switch that is
located in the lower left corner of the a/c heater con-
trol unit face plate. The heated mirror system helps
the vehicle operator maintain outside rear view mir-
ror visibility during inclement operating conditions
by keeping both outside mirror glasses clear of ice,
snow, or fog. The heated mirror system for this vehi-
cle includes the following major components:
²The heated mirror switch, including the heated
mirror system solid state electronic control logic and
timer circuitry, the heated mirror relay and the
heated mirror system indicator lamp. All of these
components are integral to the a/c heater control unit
on the instrument panel.
²The two outside mirror heating grids, which are
integral to the power outside mirror units.
Following are general descriptions of the major
components in the heated mirror system. See the
owner's manual in the vehicle glove box for more
information on the features, use and operation of the
heated mirror system.
OPERATION - HEATED MIRROR SYSTEM
The solid state electronic control logic and timer
circuitry for the heated mirror system receives bat-
tery current from a fuse in the Junction Block (JB)
only when the ignition switch is in the On or Start
positions. After the heated mirror system is turned
On, the electronic control logic and timer circuitry
will automatically turn the system off after a pro-
grammed time interval of about fifteen minutes.
After the initial time interval has expired, if the
Fig. 1 HEATED MIRROR- typical
1 - POWER HEATED OUTSIDE REAR VIEW MIRROR
2 - REAR WINDOW DEFOGGER ICON
DRHEATED SYSTEMS 8G - 1

heated mirror switch is depressed and released a sec-
ond time during the same ignition cycle, the elec-
tronic control logic and timer circuitry will
automatically turn the heated mirror system off after
a programmed time interval of about five minutes.
The heated mirror system will be shut off automati-
cally if the ignition switch is turned to the Off or
Accessory positions. After the heated mirror system
is turned On, it can also be turned off manually by
depressing and releasing the heated mirror switch a
second time.
When the heated mirror system is turned On, the
heated mirror system control logic and timer cir-
cuitry energizes the heated mirror system indicator
lamp and the heated mirror relay. When energized,
the heated mirror relay supplies fused ignition
switch output (run/start) current from a fuse in the
JB to the outside mirror heating grids located behind
the mirror glass of each of the outside rear view mir-
rors. When energized, each of the outside mirror
heating grids produces enough heat to warm the
glass of the outside rear view mirrors.
DIAGNOSIS AND TESTING - HEATED MIRROR
SYSTEM
If only one of the outside mirror heating grids is
inoperative, perform continuity checks on the circuits
and heater grid for that mirror only. If both outside
mirror heating grids are inoperative, proceed with
the heated mirror system diagnosis as follows. (Refer
to Appropriate Wiring Information).
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, DISABLE THE AIRBAG SYSTEM BEFORE
ATTEMPTING ANY STEERING WHEEL, STEERING
COLUMN, OR INSTRUMENT PANEL COMPONENT
DIAGNOSIS OR SERVICE. DISCONNECT AND ISO-
LATE THE BATTERY NEGATIVE (GROUND) CABLE,
THEN WAIT TWO MINUTES FOR THE AIRBAG SYS-
TEM CAPACITOR TO DISCHARGE BEFORE PER-
FORMING FURTHER DIAGNOSIS OR SERVICE. THIS
IS THE ONLY SURE WAY TO DISABLE THE AIRBAG
SYSTEM. FAILURE TO TAKE THE PROPER PRE-
CAUTIONS COULD RESULT IN ACCIDENTAL AIR-
BAG DEPLOYMENT AND POSSIBLE PERSONAL
INJURY.The operation of the heated mirror system can be
confirmed in one of the following manners:
1. Turn the ignition switch to the On position.
While monitoring the instrument panel voltmeter,
momentarily depress and release the heated mirror
switch. When the heated mirror system is turned On,
a distinct voltmeter needle deflection should be
noted.
2. Turn the ignition switch to the On position.
Momentarily depress and release the heated mirror
switch to turn the heated mirror system On. The
heated mirror operation can be checked by feeling
the outside rear view mirror glass. A distinct differ-
ence in temperature between the unheated and
heated mirror glass can be detected within three to
four minutes of system operation.
The above checks will confirm system operation.
Illumination of the heated mirror system indicator
lamp means that there is electrical current available
at the heated mirror relay, but does not confirm that
the electrical current is reaching the outside mirror
heating grids.
If the heated mirror system does not operate, the
problem should be isolated in the following manner:
(1) Confirm that the ignition switch is in the On
position.
(2) Check the fuses in the Power Distribution Cen-
ter (PDC) and in the Junction Block (JB). The fuses
must be tight in their receptacles and all electrical
connections must be secure.
When the above steps have been completed and
both outside mirror heating grids are still inopera-
tive, one or more of the following is faulty:
²Heated mirror switch, electronic control logic
and timer circuitry, and heated mirror relay.
²Heated mirror wire harness circuits or connec-
tors.
²Outside mirror heating grid (both mirror grids
would have to be faulty).
If turning On the heated mirror system produces a
severe voltmeter deflection or fuse failures, check for
a shorted circuit between the output of the heated
mirror relay and the outside mirror heating grids.
8G - 2 HEATED MIRRORSDR
HEATED MIRRORS (Continued)