radio CHRYSLER CARAVAN 2002 Owner's Manual

(4) Install the battery in the vehicle. Refer to the
procedure in Battery Systems.
(5) Connect the positive and negative battery
cables.
(6) Using the DRB IIIt, under ªFRONT CON-
TROL MODULEº then ªMISCº program the EQ
curve of the radio into the Front Control Module.
Refer to the appropriate diagnostic manual.
NOTE: If the vehicle is not equipped with Name
Brand Speakers (Infinity, etc.) or Headlamp Washers
the DRB IIITmust be used to Disable the appropri-
ate relays in the Intelligent Power Module Assembly.
HEATED SEAT MODULE
DESCRIPTION
Vehicles equipped with heated seats utilize two
heated seat modules. The heated seat modules (Fig.
8) are located under the front seats, where they are
secured to the seat cushion pans. The left heated
seat module controls the left heated seat, and the
right controls the right. Each heated seat module has
three connector receptacles that allows the module to
be connected to all of the required inputs and out-
puts through the seat wire harness.The heated seat module is an electronic micropro-
cessor controlled device designed and programmed to
use inputs from the ignition switch, heated seat
switch and the heated seat sensor to operate and
control the heated seat elements in the front seat
and the two heated seat indicator lamp Light-Emit-
ting Diodes (LEDs) in the heated seat switch.
The heated seat module cannot be repaired. If the
heated seat module is damaged or faulty, the entire
module must be replaced.
OPERATION
The heated seat module operates on fused battery
current received from the ignition switch and inte-
grated power module. The module is grounded at all
times through the seat wire harness. Inputs to the
module include a resistor multiplexed heated seat
switch request circuit for the heated seat switch and
the heated seat sensor inputs from the seat cushions
of each front seat. In response to those inputs the
heated seat module controls battery current feeds to
the heated seat elements, and controls the ground for
the heated seat switch indicator lamps.
When a heated seat switch request signal is
received by the heated seat module, the module ener-
gizes the proper indicator lamp (Low or High) in the
switch by grounding the indicator lamp circuit to
indicate that the heated seat system is operating. At
the same time, the heated seat module energizes the
selected heated seat sensor circuit and the sensor
provides the module with an input indicating the
surface temperature of the selected seat cushion.
The Low heat set point is about 38É C (100.4É F),
and the High heat set point is about 42É C (107.6É F).
If the seat cushion surface temperature input is
below the temperature set point for the selected tem-
perature setting, the heated seat module energizes
an N-channel Field Effect Transistor (N-FET) within
the module which energizes the heated seat elements
in the selected seat cushion and back. When the sen-
sor input to the module indicates the correct temper-
ature set point has been achieved, the module
de-energizes the N-FET which de-energizes the
heated seat elements. The heated seat module will
continue to cycle the N-FET as needed to maintain
the selected temperature set point.
DIAGNOSIS AND TESTING - HEATED SEAT
MODULE
If a heated seat fails to heat and one or both of the
indicator lamps on a heated seat switch flash, refer
toDiagnosis and Testing Heated Seat Systemin
Heated Seats for the location of flashing LED heated
seat system diagnosis and testing procedures. If a
heated seat heats but one or both indicator lamps on
the heated seat switch fail to operate, test the heated
Fig. 8 RS/RG Heated Seat Modules
1 - HEATED SEAT MODULE
2 - C1 CONNECTOR
3 - C3 CONNECTOR
4 - C1 CONNECTOR
RSELECTRONIC CONTROL MODULES8E-9
FRONT CONTROL MODULE (Continued)
ProCarManuals.com

(2) Turn the ignition switch on and access the
ªRead Faultº screen.
(3) Record all the DTC's and ªfreeze frameº infor-
mation shown on the DRB scan tool.
(4) To erase DTC's, use the ªErase Trouble Codeº
data screen on the DRB scan tool.Do not erase any
DTC's until problems have been investigated
and repairs have been performed.
OBTAINING DTC'S USING IGNITION KEY
(1) Cycle the ignition key On - Off - On - Off - On
within 5 seconds.
(2) The Odometer will show the P-code for the
DTC code number. Refer to the Emission section for
the DTC chart for a detailed explanation of the DTC
codes.
(3) If no DTC's are present, the cluster will display
one of two texts: ªP1684º and ªdoneº or only ªdoneº.
²P1684 is only a status and indicates that the
PCM memory has been cleared within the last 50
ignition cycles and does not indicate a problem.
²done indicates that NO DTCs are present and
the procedure is complete.
REMOVAL
(1) Disconnect the negative battery cable.
(2) Remove the battery shield, refer to the Battery
section for more information.
(3) Remove the 2 upper PCM bracket bolts (Fig.
12).(4) Remove the 2 PCM connectors.
(5) Remove the headlamp, refer to the Lamps sec-
tion for more information.
(6) Remove the lower PCM mounting bolt (Fig. 13).
(7) Remove PCM.
INSTALLATION
(1) Install the PCM.
(2) Install the lower PCM mounting bolt. Tighten
bolt.
(3) Install the 2 upper PCM bracket bolts. Tighten
bolt.
(4) Install the headlamp, refer to the Lamps sec-
tion for more information.
(5) Install the 2 PCM connectors.
(6) Install the battery shield, refer to the Battery
section for more information.
(7) Connect the negative battery cable.
SENTRY KEY IMMOBILIZER
MODULE
DESCRIPTION
The Sentry Key Immobilizer Module (SKIM) con-
tains a Radio Frequency (RF) transceiver and a
microprocessor. The SKIM retains in memory the ID
numbers of any Sentry Key that is programmed to it.
The maximum number of keys that may be pro-
grammed to each module is eight (8). The SKIM also
communicates over the PCI bus with the Powertrain
Control Module (PCM), the Body Control Module
Fig. 12 PCM
1 - Attaching Bolts
Fig. 13 PCM LOWER BOLT
8E - 26 ELECTRONIC CONTROL MODULESRS
POWERTRAIN CONTROL MODULE (Continued)
ProCarManuals.com

these sensor inputs to adjust fuel quantity and fuel
injector timing.
Limp-In Mode
If there is a fault detected with the accelerator
pedal position sensor, the ECM will set the engine
speed at 1100 RPM.
Overspeed Detection Mode
If the ECM detects engine RPM that exceeds 5200
RPM, the ECM will set a DTC in memory and illu-
minate the MIL until the DTC is cleared.
After-Run Mode
The ECM transfers RAM information to ROM and
performs an Input/Output state check.
MONITORED CIRCUITS
The ECM is able to monitor and identify most
driveability related trouble conditions. Some circuits
are directly monitored through ECM feedback cir-
cuitry. In addition, the ECM monitors the voltage
state of some circuits and compares those states with
expected values. Other systems are monitored indi-
rectly when the ECM conducts a rationality test to
identify problems. Although most subsytems of the
engine control module are either directly or indirectly
monitored, there may be occasions when diagnostic
trouble codes are not immediately identified. For a
trouble code to set, a specific set of conditions must
occur and unless these conditions occur, a DTC will
not set.
DIAGNOSTIC TROUBLE CODES
Each diagnostic trouble code (DTC) is diagnosed by
following a specific procedure. The diagnostic test
procedure contains step-by-step instruction for deter-
mining the cause of the DTC as well as no trouble
code problems. Refer to the appropriate Diesel Pow-
ertrain Diagnostic Manual for more information.
HARD CODE
A DTC that comes back within one cycle of the
ignition key is a hard code. This means that the
problem is current every time the ECM/SKIM checks
that circuit or function. Procedures in this manual
verify if the DTC is a hard code at the beginning of
each test. When the fault is not a hard code, an
intermittent test must be performed. NOTE: If the
DRBIIItdisplays faults for multiple components (i.e.
ECT, VSS, IAT sensors) identify and check the
shared circuits for possible problems before continu-
ing (i.e. sensor grounds or 5-volt supply circuits).
Refer to the appropriate schematic to identify shared
circuits. Refer to the appropriate Diesel Powertrain
Diagnostic Manual for more information.INTERMITTENT CODE
A DTC that is not current every time the ECM/
SKIM checks the circuit or function is an intermit-
tent code. Most intermittent DTCs are caused by
wiring or connector problems. Problems that come
and go like this are the most difficult to diagnose;
they must be looked for under specific conditions that
cause them.NOTE: Electromagnetic (radio)
interference can cause an intermittent system
malfunction.This interference can interrupt com-
munication between the ignition key transponder and
the SKIM. The following checks may assist you in
identifying a possible intermittent problem:
²Visually inspect the related wire harness connec-
tors. Look for broken, bent, pushed out or corroded
terminals.
²Visually inspect the related wire harness. Look
for chafed, pierced or partially broken wire.
²Refer to hotlines or technical service bulletins
that may apply. Refer to the appropriate Diesel Pow-
ertrain Diagnostic Manual for more information.
ECM DIAGNOSTIC TROUBLE CODES
IMPORTANT NOTE: Before replacing the ECM 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 ECM driver/control circuit failures are
caused by internal failures to components (i.e. relays
and solenoids) and shorted circuits (i.e. sensor pull-
ups, drivers and ground circuits). These faults are
difficult to detect when a double fault has occurred
and only one DTC has set. If the DRBIIItdisplays
faults for multiple components (i.e.VSS, ECT, Batt
Temp, etc.) identify and check the shared circuits for
possible problems before continuing (i.e. sensor
grounds or 5-volt supply circuits). Refer to the appro-
priate wiring diagrams to identify shared circuits.
Refer to the appropriate Diesel Powertrain Diagnos-
tic Manual for more information.
STANDARD PROCEDURE - PCM/ECM/SKIM
PROGRAMMING - DIESEL
NOTE: Before replacing the PCM/ECM 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 cir-
cuit. Most PCM/ECM driver/control circuit failures
are caused by internal component failures (i.e. relay
and solenoids) 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 set.
8Ea - 2 ELECTRONIC CONTROL MODULESRG
ENGINE CONTROL MODULE (Continued)
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CONVENTIONAL BATTERY CHARGING TIME TABLE
Charging
Amperage5 Amps10
Amps20 Amps
Open Circuit
VoltageHours Charging @ 21É C (70É
F)
12.25 to 12.49 6 hours 3 hours 1.5
hours
12.00 to 12.24 10 hours 5 hours 2.5
hours
10.00 to 11.99 14 hours 7 hours 3.5
hours
Below 10.00 18 hours 9 hours 4.5
hours
STANDARD PROCEDURE - OPEN-CIRCUIT
VOLTAGE TEST
A battery open-circuit voltage (no load) test will
show the approximate state-of-charge of a battery.
This test can be used if no other battery tester is
available.
Before proceeding with this test, completely charge
the battery. Refer to Standard Procedures for the
proper battery charging procedures.
(1) Before measuring the open-circuit voltage, the
surface charge must be removed from the battery.
Turn on the headlamps for fifteen seconds, then
allow up to five minutes for the battery voltage to
stabilize.
(2) Disconnect and isolate both battery cables, neg-
ative cable first.
(3) Using a voltmeter connected to the battery
posts (see the instructions provided by the manufac-
turer of the voltmeter), measure the open-circuit volt-
age (Fig. 9).
See the Open-Circuit Voltage Table. This voltage
reading will indicate the battery state-of-charge, but
will not reveal its cranking capacity. If a battery has
an open-circuit voltage reading of 12.4 volts orgreater, it may be load tested to reveal its cranking
capacity. Refer to Standard Procedures for the proper
battery load test procedures.
OPEN CIRCUIT VOLTAGE TABLE
Open Circuit Voltage Charge Percentage
11.7 volts or less 0%
12.0 volts 25%
12.2 volts 50%
12.45 volts 75%
12.65 volts or more 100%
STANDARD PROCEDURE - IGNITION-OFF
DRAW TEST
The term Ignition-Off Draw (IOD) identifies a nor-
mal condition where power is being drained from the
battery with the ignition switch in the Off position. A
normal vehicle electrical system will draw from five
to thirty-five milliamperes (0.015 to 0.025 ampere)
with the ignition switch in the Off position, and all
non-ignition controlled circuits in proper working
order. Up to twenty-five milliamperes are needed to
enable the memory functions for the Powertrain Con-
trol Module (PCM), digital clock, electronically tuned
radio, and other modules which may vary with the
vehicle equipment.
A vehicle that has not been operated for approxi-
mately twenty-one days, may discharge the battery
to an inadequate level. When a vehicle will not be
used for twenty-one days or more (stored), remove
the IOD fuse from the Integrated Power Module
(IPM). This will reduce battery discharging.
Excessive IOD can be caused by:
²Electrical items left on.
²Faulty or improperly adjusted switches.
²Faulty or shorted electronic modules and compo-
nents.
²An internally shorted generator.
²Intermittent shorts in the wiring.
If the IOD is over twenty-five milliamperes, the
problem must be found and corrected before replac-
ing a battery. In most cases, the battery can be
charged and returned to service after the excessive
IOD condition has been corrected.
(1) Verify that all electrical accessories are off.
Turn off all lamps, remove the ignition key, and close
all doors. If the vehicle is equipped with an illumi-
nated entry system or an electronically tuned radio,
allow the electronic timer function of these systems
to automatically shut off (time out). This may take
up to three minutes.
(2) Disconnect the battery negative cable.
(3) Set an electronic digital multi-meter to its
highest amperage scale. Connect the multi-meter
Fig. 9 Testing Open-Circuit Voltage - Typical
RSBATTERY SYSTEM8F-13
BATTERY (Continued)
ProCarManuals.com

F). When a fast battery charger is connected to a cold
battery, the current accepted by the battery will be
very low at first. As the battery warms, it will accept
a higher charging current rate (amperage).
²Charger Capacity- A battery charger that
supplies only five amperes will require a longer
charging time. A battery charger that supplies
twenty amperes or more will require a shorter charg-
ing time.
²State-Of-Charge- A completely discharged bat-
tery requires more charging time than a partially
discharged battery. Electrolyte is nearly pure water
in a completely discharged battery. At first, the
charging current (amperage) will be low. As the bat-
tery charges, the specific gravity of the electrolyte
will gradually rise.
The Conventional Battery Charging Time Table
gives an indication of the time required to charge a
typical battery at room temperature based upon the
battery state-of-charge and the charger capacity.
CONVENTIONAL BATTERY CHARGING TIME
TABLE
Charging
Amperage5 Amps10
Amps20 Amps
Open Circuit
VoltageHours Charging @ 21É C (70É F)
12.25 to 12.49 6 hours 3 hours 1.5 hours
12.00 to 12.24 10 hours 5 hours 2.5 hours
10.00 to 11.99 14 hours 7 hours 3.5 hours
Below 10.00 18 hours 9 hours 4.5 hours
STANDARD PROCEDURE - OPEN-CIRCUIT
VOLTAGE TEST
A battery open-circuit voltage (no load) test will show
the approximate state-of-charge of a battery. This test
can be used if no other battery tester is available.
Before proceeding with this test, completely charge
the battery. Refer to Standard Procedures for the
proper battery charging procedures.
(1)
Before measuring the open-circuit voltage, the
surface charge must be removed from the battery.
Turn on the headlamps for fifteen seconds, then allow
up to five minutes for the battery voltage to stabilize.
(2) Disconnect and isolate both battery cables, neg-
ative cable first.
(3) Using a voltmeter connected to the battery
posts (see the instructions provided by the manufac-
turer of the voltmeter), measure the open-circuit volt-
age (Fig. 9).
See the Open-Circuit Voltage Table. This voltage
reading will indicate the battery state-of-charge, but
will not reveal its cranking capacity. If a battery has
an open-circuit voltage reading of 12.4 volts orgreater, it may be load tested to reveal its cranking
capacity. Refer to Standard Procedures for the proper
battery load test procedures.
OPEN CIRCUIT VOLTAGE TABLE
Open Circuit Voltage Charge Percentage
11.7 volts or less 0%
12.0 volts 25%
12.2 volts 50%
12.45 volts 75%
12.65 volts or more 100%
STANDARD PROCEDURE - IGNITION-OFF
DRAW TEST
The term Ignition-Off Draw (IOD) identifies a nor-
mal condition where power is being drained from the
battery with the ignition switch in the Off position. A
normal vehicle electrical system will draw from five
to thirty-five milliamperes (0.015 to 0.025 ampere)
with the ignition switch in the Off position, and all
non-ignition controlled circuits in proper working
order. Up to twenty-five milliamperes are needed to
enable the memory functions for the Powertrain Con-
trol Module (PCM), digital clock, electronically tuned
radio, and other modules which may vary with the
vehicle equipment.
A vehicle that has not been operated for approxi-
mately twenty-one days, may discharge the battery
to an inadequate level. When a vehicle will not be
used for twenty-one days or more (stored), remove
the IOD fuse from the Integrated Power Module
(IPM). This will reduce battery discharging.
Excessive IOD can be caused by:
²Electrical items left on.
²Faulty or improperly adjusted switches.
²Faulty or shorted electronic modules and compo-
nents.
²An internally shorted generator.
Fig. 9 Testing Open-Circuit Voltage - Typical
RGBATTERY SYSTEM8Fa-13
BATTERY (Continued)
ProCarManuals.com

²Intermittent shorts in the wiring.
If the IOD is over twenty-five milliamperes, the
problem must be found and corrected before replac-
ing a battery. In most cases, the battery can be
charged and returned to service after the excessive
IOD condition has been corrected.
(1) Verify that all electrical accessories are off.
Turn off all lamps, remove the ignition key, and close
all doors. If the vehicle is equipped with an illumi-
nated entry system or an electronically tuned radio,
allow the electronic timer function of these systems
to automatically shut off (time out). This may take
up to three minutes.
(2) Disconnect the battery negative cable.
(3) Set an electronic digital multi-meter to its
highest amperage scale. Connect the multi-meter
between the disconnected battery negative cable ter-
minal clamp and the battery negative terminal post.
Make sure that the doors remain closed so that the
illuminated entry system is not activated. The multi-
meter amperage reading may remain high for up to
three minutes, or may not give any reading at all
while set in the highest amperage scale, depending
upon the electrical equipment in the vehicle. The
multi-meter leads must be securely clamped to the
battery negative cable terminal clamp and the bat-
tery negative terminal post. If continuity between the
battery negative terminal post and the negative cable
terminal clamp is lost during any part of the IOD
test, the electronic timer function will be activated
and all of the tests will have to be repeated.
(4) After about three minutes, the high-amperage
IOD reading on the multi-meter should become very
low or nonexistent, depending upon the electrical
equipment in the vehicle. If the amperage reading
remains high, remove and replace each fuse or circuit
breaker in the Integrated Power Module (IPM), one
at a time until the amperage reading becomes very
low, or nonexistent. Refer to the appropriate wiring
information in this service manual for complete Inte-
grated Power Module fuse, circuit breaker, and cir-
cuit identification. This will isolate each circuit and
identify the circuit that is the source of the high-am-
perage IOD. If the amperage reading remains high
after removing and replacing each fuse and circuit
breaker, disconnect the wire harness from the gener-
ator. If the amperage reading now becomes very low
or nonexistent, refer to Charging System for the
proper charging system diagnosis and testing proce-
dures. After the high-amperage IOD has been cor-
rected, switch the multi-meter to progressively lower
amperage scales and, if necessary, repeat the fuse
and circuit breaker remove-and-replace process to
identify and correct all sources of excessive IOD. It is
now safe to select the lowest milliampere scale of the
multi-meter to check the low-amperage IOD.CAUTION: Do not open any doors, or turn on any
electrical accessories with the lowest milliampere
scale selected, or the multi-meter may be damaged.
(5) Allow twenty minutes for the IOD to stabilize
and observe the multi-meter reading. The low-amper-
age IOD should not exceed twenty-five milliamperes
(0.025 ampere). If the current draw exceeds twenty-
five milliamperes, isolate each circuit using the fuse
and circuit breaker remove-and-replace process in
Step 4. The multi-meter reading will drop to within
the acceptable limit when the source of the excessive
current draw is disconnected. Repair this circuit as
required; whether a wiring short, incorrect switch
adjustment, or a component failure is at fault.
STANDARD PROCEDURE - CHECKING BATTERY
ELECTROLYTE LEVEL
The following procedure can be used to check the
electrolyte level in a low-maintenance lead-acid bat-
tery.
(1) Unscrew and remove the battery cell caps with
a flat-bladed screw driver (Fig. 10).
WARNING: NEVER PUT YOUR FACE NEAR A GAS-
SING, HOT OR SWELLED BATTERY. SERIOUS PER-
SONAL INJURY MAY RESULT.
Fig. 10 BATTERY CELL CAP REMOVAL/
INSTALLATION - LOW-MAINTENANCE BATTERY
ONLY
1 - BATTERY CELL CAP
2 - BATTERY CASE
8Fa - 14 BATTERY SYSTEMRG
BATTERY (Continued)
ProCarManuals.com

HEATED SEAT SYSTEM
TABLE OF CONTENTS
page page
HEATED SEAT SYSTEM
DESCRIPTION..........................7
OPERATION............................8
DIAGNOSIS AND TESTING - HEATED SEAT
SYSTEM.............................8
DRIVER HEATED SEAT SWITCH
DESCRIPTION..........................9
OPERATION............................9
DIAGNOSIS AND TESTING - DRIVER HEATED
SEAT SWITCH.........................9
REMOVAL.............................10
INSTALLATION.........................10
HEATED SEAT ELEMENT
DESCRIPTION.........................11
OPERATION...........................11
DIAGNOSIS AND TESTING - HEATED SEAT
ELEMENTS..........................11REMOVAL.............................12
INSTALLATION.........................12
HEATED SEAT SENSOR
DESCRIPTION.........................12
OPERATION...........................12
DIAGNOSIS AND TESTING - HEATED SEAT
SENSOR............................12
PASSENGER HEATED SEAT SWITCH
DESCRIPTION.........................13
OPERATION...........................13
DIAGNOSIS AND TESTING - PASSENGER
HEATED SEAT SWITCH.................13
REMOVAL.............................14
INSTALLATION.........................15
HEATED SEAT SYSTEM
DESCRIPTION
Vehicles with the heated seat option can be visu-
ally identified by the two separate heated seat
switches located in the instrument panel center
stack, just above the radio (Fig. 1). The heated seat
system allows the front seat driver and passenger to
select from two different levels of supplemental elec-
trical seat heating (HI/LO), or no seat heating to suit
their individual comfort requirements. The heated
seat system for this vehicle includes the following
major components, which are described in further
detail later in this section:
²Heated Seat Elements- Four heated seat ele-
ments are used per vehicle, two for each front seat.
One heated seat element is integral to each front
seat trim cover, one in the seat back and one in the
seat bottom (cushion). Service replacement heating
elements are available, refer to heated seat elements
later in this section for additional information.
²Heated Seat Modules- Two heated seat mod-
ules are used per vehicle. One module is mounted to
each of the seat cushion pans, located under the for-
ward edge of each front seat. Refer to heated seat
module in the electronic control modules section of
the service manual for additional information.
²Heated Seat Sensors- Two heated seat sen-
sors are used per vehicle, one for each front seat. The
heated seat sensors are integral to each of the heated
seat bottoms (cushions).
Fig. 1 HEATED SEAT SWITCH LOCATIONS
1 - HEATED SEAT SWITCHES
RSHEATED SEAT SYSTEM8G-7
ProCarManuals.com

(3) On All Wheel Drive vehicles install the PTU
(Power Transfer Unit) for the rear wheels, refer to
the Transmission section for more information.
(4) Lower vehicle.
(5) Connect the negative cable.
SPARK PLUG
DESCRIPTION
DESCRIPTION - STANDARD 4 CYLINDER
All engines use resistor spark plugs. They have
resistance values ranging from 6,000 to 20,000 ohms
when checked with at least a 1000 volt spark plug
tester.
Do not use an ohm meter to check the resis-
tance of the spark plugs. This will give an inac-
curate reading.
Refer to the Specifications section for gap and type
of spark plug.
DESCRIPTION - PLATINUM PLUGS
The V6 engines use platinum resistor spark plugs.
They have resistance values of 6,000 to 20,000 ohms
when checked with at least a 1000 volt tester. Forspark plug identification and specifications, Refer to
the Specifications section.
Do not use an ohm meter to check the resis-
tance of the spark plugs. This will give an inac-
curate reading.
When the spark plugs use a single or double plat-
inum tips and they have a recommended service life
of 100,000 miles for normal driving conditions per
schedule A in this manual. The spark plugs have a
recommended service life of 75,000 miles for severe
driving conditions per schedule B in this manual. A
thin platinum pad is welded to both or center elec-
trode end(s) as show in (Fig. 13). Extreme care must
be used to prevent spark plug cross threading, mis-
gaping (Fig. 14) and ceramic insulator damage dur-
ing plug removal and installation.
CAUTION: Cleaning of the platinum plug may dam-
age the platinum tip.
REMOVAL
When replacing the spark plugs and spark plug
cables, route the cables correctly and secure them in
the appropriate retainers. Failure to route the cables
properly can cause the radio to reproduce ignition
noise, cross ignition of the spark plugs orshort cir-
cuit the cables to ground.
Always remove cables by grasping at the boot,
rotating the boot 1/2 turn, and pulling straight back
in a steady motion.
(1) Prior to removing the spark plug, spray com-
pressed air around the spark plug hole and the area
around the spark plug.
(2) Remove the spark plug using a quality socket
with a foam insert.
(3) Inspect the spark plug condition.
Fig. 12 Knock Sensor
1 - GENERATOR
2 - INTAKE MANIFOLD
3 - KNOCK SENSOR
4-STARTER
Fig. 13 Platinum Pads
1 - APPLY ANTI-SEIZE COMPOUND HERE ONLY
2 - PLATINUM SPARK SURFACE
RSIGNITION CONTROL8I-9
KNOCK SENSOR (Continued)
ProCarManuals.com

INSTALLATION
When replacing the spark plugs and spark plug
cables, route the cables correctly and secure them in
the appropriate retainers. Failure to route the cables
properly can cause the radio to reproduce ignition
noise, cross ignition of the spark plugs orshort cir-
cuit the cables to ground.
(1) To avoid cross threading, start the spark plug
into the cylinder head by hand.
(2) Tighten spark plugs to 17.5 N´m (13 ft. lbs.)
torque.
(3) Install spark plug cables over spark plugs. A
click will be heard and felt when the cable properly
attaches to the spark plug.
SPARK PLUG CABLE
DESCRIPTION
Spark Plug cables are sometimes referred to as
secondary ignition wires. The wires transfer electri-
cal current from the ignition coil pack to individual
spark plugs at each cylinder. The resistive spark plug
cables are of nonmetallic construction. The cables
provide suppression of radio frequency emissions
from the ignition system.
Check the spark plug cable connections for good
contact at the coil, and spark plugs. Terminals should
be fully seated. The insulators should be in good con-
dition and should fit tightly on the coil, and spark
plugs. Spark plug cables with insulators that are
cracked or torn must be replaced.
Clean Spark Plug cables with a cloth moistened
with a non-flammable solvent. Wipe the cables dry.
Check for brittle or cracked insulation. The spark
plug cables and spark plug boots are made from high
temperature silicone materials. All spark plug cable
leads are properly identified with cylinder numbers.
The inside of most the spark plug boot is coated with
a special high temperature silicone grease for greater
sealing and to minimize boot bonding to the spark
plug insulator.
REMOVAL
Failure to route the cables properly could cause the
radio to reproduce ignition noise, cross ignition of the
spark plugs or short circuit the cables to ground.
Remove spark plug cable from coil first.
Always remove the spark plug cable by grasping
the top of the spark plug insulator, turning the boot
1/2 turn and pulling straight up in a steady motion.
INSTALLATION
Failure to route the cables properly could cause the
radio to reproduce ignition noise, cross ignition of the
spark plugs or short circuit the cables to ground.
Install spark plug insulators over spark plugs.
Ensure the top of the spark plug insulator covers the
upper end of the spark plug tube, then connect the
other end to coil pack.
Fig. 14 Setting Spark Plug Electrode Gap
1 - TAPER GAUGE
8I - 10 IGNITION CONTROLRS
SPARK PLUG (Continued)
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ules push buttons located just rearward of the dis-
play screen in the overhead console. The three
universal transmitter push buttons are identified
with one, two or three light indicators so that they be
easily identified by sight or by feel.
Each of the three universal transmitter push but-
tons controls an independent radio transmitter chan-
nel. Each of these three channels can be trained to
transmit a different radio frequency signal for the
remote operation of garage door openers, motorized
gate openers, home or office lighting, security sys-
tems or just about any other device that can be
equipped with a radio receiver in the 286 to 399
MegaHertz (MHz) frequency range for remote opera-
tion. The universal transmitter is capable of operat-
ing systems using either rolling code or non-rolling
code technology.
The electronics module displays messages and a
small house-shaped icon with one, two or three dots
corresponding to the three transmitter buttons to
indicate the status of the universal transmitter. The
EVIC messages are:
²Cleared Channels- Indicates that all of the
transmitter codes stored in the universal transmitter
have been successfully cleared.
²Training- Indicates that the universal trans-
mitter is in its transmitter learning mode.
²Trained- Indicates that the universal transmit-
ter has successfully acquired a new transmitter code.
²Transmit- Indicates that a trained universal
transmitter button has been depressed and that the
universal transmitter is transmitting.
The universal transmitter cannot be repaired, and
is available for service only as a unit with the EVIC
or CMTC modules. If any of these components is
faulty or damaged, the complete EVIC or CMTC
module must be replaced.
OPERATION
The universal transmitter operates on a non-
switched source of battery current so the unit will
remain functional, regardless of the ignition switch
position. For more information on the features, pro-
gramming procedures and operation of the universal
transmitter, see the owner's manual in the vehicle
glove box.
DIAGNOSIS AND TESTING - UNIVERSAL
TRANSMITTER
If the universal transmitter is inoperative, but the
Electronic Vehicle Information Center (EVIC) or
Compass Mini-Trip Computer is operating normally,
see the owner's manual in the vehicle glove box for
instructions on training the universal transmitter.
Retrain the universal transmitter with a known good
transmitter as instructed in the owner's manual andtest the universal transmitter operation again. If the
unit is still inoperative, replace the faulty universal
transmitter and EVIC/CMTC module as a unit. If
both the universal transmitter and the EVIC/CMTC
module are inoperative, refer toOverhead Console
Diagnosis and Testingearlier in this group for fur-
ther diagnosis. For complete circuit diagrams, refer
toOverhead Consolein Wiring Diagrams.
AMBIENT TEMP SENSOR
DESCRIPTION
Ambient air temperature is monitored by the over-
head console through ambient temperature messages
received from the Front Control Module (FCM) over
the Programmable Communications Interface (PCI)
J1850 data bus circuit. The FCM receives a hard
wired input from the ambient temperature sensor.
The ambient temperature sensor is a variable resis-
tor mounted to a bracket that is secured with a screw
to the right side of the headlamp mounting module
grille opening, behind the radiator grille and in front
of the engine compartment.
Refer toFront Control Modulein Electronic
Control Modules. For complete circuit diagrams, refer
to the appropriate wiring information. The ambient
temperature sensor cannot be adjusted or repaired
and, if faulty or damaged, it must be replaced.
OPERATION
The ambient temperature sensor is a variable
resistor that operates on a five-volt reference signal
sent to it by the Front Control Module. The resis-
tance in the sensor changes as temperature changes,
changing the temperature sensor signal circuit volt-
age to the Front Control Module. Based upon the
resistance in the sensor, the Front Control Module
senses a specific voltage on the temperature sensor
signal circuit, which it is programmed to correspond
to a specific temperature. The Front Control Module
then sends the proper ambient temperature mes-
sages to the EVIC, CMTC over the PCI J1850 data
bus.
The thermometer function is supported by the
ambient temperature sensor, a wiring circuit, the
Front Control Module, the Programmable Communi-
cations Interface (PCI) data bus, and a portion of the
Electronics module. If any portion of the ambient
temperature sensor circuit fails, the Front Control
Module will self-diagnose the circuit.
The ambient temperature sensor circuit can also be
diagnosed by referring toDiagnosis and Testing -
Ambient Temperature Sensor, and Diagnosis
and Testing - Ambient Temperature Sensor Cir-
cuit. If the temperature sensor and circuit are con-
8M - 10 MESSAGE SYSTEMSRS
UNIVERSAL TRANSMITTER (Continued)
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