2001 DODGE TOWN AND COUNTRY turn signal

SKIM is properly installed on the steering column,
the antenna ring fits snugly around the circumfer-
ence of the ignition lock cylinder housing. If this ring
is not mounted properly, communication problems
may arise in the form of transponder-related faults.
For added system security, each SKIM is pro-
grammed with a unique9Secret Key9code. This code
is stored in memory and is sent over the PCI bus to
the PCM and to each key that is programmed to
work with the vehicle. The9Secret Key9code is there-
fore a common element found in all components of
the Sentry Key Immobilizer System (SKIS). In the
event that a SKIM replacement is required, the
9Secret Key9code can be restored from the PCM by
following the SKIM replacement procedure found in
the DRB IIItscan tool. Proper completion of this
task will allow the existing ignition keys to be repro-
grammed. Therefore, new keys will NOT be needed.
In the event that the original9Secret Key9code can
not be recovered, new ignition keys will be required.
The DRB IIItscan tool will alert the technician if
key replacement is necessary. Another security code,
called a PIN, is used to gain secured access to the
SKIM for service. The SKIM also stores in its mem-
ory the Vehicle Identification Number (VIN), which it
learns through a bus message from the assembly
plant tester. The SKIS scrambles the information
that is communicated between its components in
order to reduce the possibility of unauthorized SKIM
access and/or disabling.
OPERATION
When the ignition switch is moved to the RUN
position, the SKIM transmits an RF signal to the
transponder in the ignition key. The SKIM then
waits for a response RF signal from the transponder
in the key. If the response received identifies the key
as valid, the SKIM sends a9valid key9message to
the PCM over the PCI bus. If the response received
identifies the key as invalid or no response is
received from the transponder in the ignition key, the
SKIM sends an9invalid key9message to the PCM.
The PCM will enable or disable engine operation
based upon the status of the SKIM messages. It is
important to note that the default condition in the
PCM is9invalid key.9Therefore, if no response is
received by the PCM, the engine will be immobilized
after two (2) seconds of running.
The SKIM also sends indicator light status mes-
sages to the BCM to operate the light. This is the
method used to turn the light ON solid or to flash it
after the indicator light test is complete to signify a
fault in the SKIS. If the light comes ON and stays
ON solid after the indicator light test, this signifies
that the SKIM has detected a system malfunction
and/or that the SKIS has become inoperative. If theSKIM detects an invalid keyORa key-related fault
exists, the indicator light will flash following the
indicator light test. The SKIM may also request an
audible chime if the customer key programming fea-
ture is available and the procedure is being utilized.
Refer to Electrical, Vehicle Theft Security, Transpon-
der Key, Standard Procedure - Transponder Program-
ming.
REMOVAL
(1) Disconnect and isolate the battery negative
cable.
(2) Remove Lower Instrument Panel Cover. Refer
to Body, Instrument Panel, Lower Instrument Panel
Cover, Removal.
(3) Remove the steering column upper and lower
shrouds. Refer to Steering, Column, Column Shroud,
Removal.
(4) Disengage the steering column wire harness
from the Sentry Key Immobilizer Module (SKIM).
(5) Remove the one screws securing the SKIM to
the steering column.
(6) Rotate the SKIM upwards and then to the side
away from the steering column to slide the SKIM
antenna ring from around the ignition switch lock
cylinder housing.
(7) Remove the SKIM from the vehicle.
INSTALLATION
(1) Slip the SKIM antenna ring around the igni-
tion switch lock cylinder housing. Rotate the SKIM
downwards and then towards the steering column.
(2) Install the one screws securing the SKIM to
the steering column.
(3) Engage the steering column wire harness from
the Sentry Key Immobilizer Module (SKIM).
(4) Install the steering column upper and lower
shrouds. Refer to Steering, Column, Column Shroud,
Installation.
(5) Install the Lower Instrument Panel Cover.
Refer to Body, Instrument Panel, Lower Instrument
Panel Cover, Installation.
(6) Connect the battery negative cable.
SLIDING DOOR CONTROL
MODULE
DESCRIPTION
Vehicles equipped with a power sliding door utilize
a sliding door control module. The sliding door con-
trol module is located behind the sliding door trim
panel in the center of the door, just above the sliding
door motor. This module controls the operation of the
door through the Programmable Communication
Interface (PCI) J1850 data bus circuit and the Body
RSELECTRONIC CONTROL MODULES8E-23
SENTRY KEY IMMOBILIZER MODULE (Continued)
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²Remote Keyless Entry Module (RKE)- Refer
toRemote Keyless Entry Modulein Power Locks
for more information.
²Electronic Vehicle Information Center
(EVIC)- Refer toElectronic Vehicle Information
Centerin Overhead Console for more information.
²Heated Seat Module (HSM)- Refer toHeated
Seat Modulein Electronic Control Modules for more
information.
²Memory Heated Seat Module (MHSM)-If
the vehicle is equipped with the Memory System,
refer toMemory Seat Mirror Module (MSMM)in
Electronic Control Modules for more information.
Refer toWiring Diagramsfor complete circuit
diagrams. Following are general descriptions of the
major components in the heated seat system.
OPERATION
The heated seat system will only operate when the
ignition switch is in the On position, and the surface
temperature at the front seat heating element sen-
sors is below the designed temperature set points of
the system. The heated seat system will not operate
in ambient temperatures greater than about 41É C
(105É F). The front seat heating elements and sensors
are hard wired to the Heated Seat Module (HSM) or
the Memory Heated Seat Module (MHSM).
The heated seat switches are hard wired to the
Body Control Module (BCM). The BCM monitors the
heated seat switch inputs, then sends heated seat
switch status messages to the HSM or MHSM over
the Programmable Communications Interface J1850
(PCI) data bus. The HSM or MHSM contains the con-
trol logic for the heated seat system. The HSM or
MHSM responds to the heated seat switch status
messages, ignition switch status messages, and the
front seat heating element sensor inputs by control-
ling the output to the front seat heating elements
through integral solid-state relays.
When a seat heater is turned on, the sensor
located on the seat cushion electric heater element
provides the HSM or MHSM with an input indicating
the surface temperature of the seat cushion. If the
surface temperature input is below the temperature
set point for the selected Low or High heated seat
switch position, the HSM or MHSM energizes the
integral solid-state relay, which supplies battery cur-
rent to the heating elements in the seat cushion and
back. When the sensor input indicates the correct
temperature set point has been achieved, the HSM or
MHSM de-energizes the solid-state relay. The HSM
or MHSM will continue to cycle the solid-state relay
as needed to maintain the temperature set point.
The HSM or MHSM and the seat heater elements
operate on non-switched battery current supplied
through the power seat fuse in the intelligent powermodule. However, the HSM or MHSM will automati-
cally turn off the heating elements if it detects an
open in the sensor circuit, a short in the heating ele-
ment circuit causing an excessive current draw, or
when the ignition switch is turned to the Off posi-
tion.
See the owner's manual in the vehicle glove box for
more information on the features, use and operation
of the heated seat system.
DRIVER HEATED SEAT
SWITCH
DESCRIPTION
The heated seat switches are mounted in the
instrument panel center bezel (Fig. 2). The two three-
position rocker-type switches, one switch for each
front seat, are incorporated into one large switch
assembly that also includes the hazzard, rear window
wiper and washer switches. The heated seat switches
provide a resistor multiplexed signal to the Body
Control Module (BCM) through separate hard wired
circuits. Each switch has an Off, Low, and High posi-
tion so that both the driver and the front seat pas-
senger can select a preferred seat heating mode.
Each switch has two Light-Emitting Diodes (LED)
which light to indicate that the heater for the seat is
turned on.
The heated seat switches and their LEDs cannot
be repaired. If either switch or LED is faulty or dam-
aged, the entire switch assembly must be replaced.
Fig. 2 HEATED SEAT SWITCHES
8G - 8 HEATED SEAT SYSTEMRS
HEATED SEAT SYSTEM (Continued)
ProCarManuals.com

OPERATION
The heated seat elements resist the flow of electri-
cal current. When battery current is passed through
the elements, the energy lost by the resistance of the
elements to the current flow is released in the form
of heat. The temperature sensor is a NTC thermistor.
When the temperature of the seat cushion cover
rises, the resistance of the sensor decreases. The
HSM or MHSM supplies a five-volt current to one
side of each sensor, and monitors the voltage drop
through the sensor on a return circuit. The MSM or
MHSM uses this temperature sensor input to moni-
tor the temperature of the seat, and regulates the
current flow to the seat heating elements accordingly.
DIAGNOSIS & TESTING - HEATED SEAT
ELEMENT
The wire harness connectors for the seat cushion
and seat back heating elements are located under the
seat, near the rear edge of the seat cushion frame.
For circuit descriptions and diagrams, refer to Group
8W, Wiring Diagrams.
SEAT CUSHION
(1) Disconnect and isolate the battery negative
cable. Unplug the 4-way heated seat cushion wire
harness connector.
(2) Check for continuity between the two heated
seat driver circuit cavities of the seat cushion cover
half of the heated seat cushion wire harness connec-
tor. There should be continuity. If OK, go to Step 3. If
not OK, replace the faulty seat cushion cover.
(3) Check for continuity between one of the heated
seat driver circuit cavities of the seat cushion cover
half of the heated seat cushion wire harness connec-
tor and the seat cushion frame. There should be no
continuity. If OK, go to the Seat Back test. If not OK,
replace the faulty seat cushion cover.
SEAT BACK
(1) Disconnect and isolate the battery negative
cable. Unplug the 2-way heated seat back wire har-
ness connector.
(2) Check for continuity between the heated seat
driver circuit cavity and the ground circuit cavity of
the seat back cover half of the heated seat back wire
harness connector. There should be continuity. If OK,
go to Step 3. If not OK, replace the faulty seat back
cover.
(3) Check for continuity between the heated seat
driver circuit cavity of the seat back cover half of the
heated seat back wire harness connector and the seat
back frame. There should be no continuity. If OK,
test the heated seat sensor as described in this
group. If not OK, replace the faulty seat back cover.
HEATED SEAT SENSOR
DESCRIPTION
The heated seat temperature sensor is a Negative
Temperature Coefficient (NTC) thermistor. One tem-
perature sensor is used for each seat, and is inte-
grated into the seat cushion heating element.
DIAGNOSIS & TESTING - HEATED SEAT
SENSOR
For complete circuit diagrams, refer toWiring
Diagrams.
(1) Disconnect and isolate the battery negative
cable. Disconnect the 4-way heated seat cushion ele-
ment wire harness connector from the power seat
wire harness. The power seat wire harness connec-
tors for the seat cushion and seat back heating ele-
ments are secured to a bracket located under the
rear edge of the seat cushion frame.
(2) Using an ohmmeter, check the resistance
between the seat sensor circuit and the seat temper-
ature sensor input circuit cavities of the 4-way
heated seat cushion element wire harness connector.
The sensor resistance should be between 2 kilohms
at 15É C (60É F) and 200 kilohms at 30É C (85É F). If
not OK, replace the faulty seat cushion cover trim
and sensor unit.
PASSENGER HEATED SEAT
SWITCH
DESCRIPTION
The heated seat switches are mounted in the
instrument panel center bezel (Fig. 5). The two three-
position rocker-type switches, one switch for each
front seat, are incorporated into one large switch
assembly that also includes the hazzard, rear window
wiper and washer switches. The heated seat switches
provide a resistor multiplexed signal to the Body
Control Module (BCM) through separate hard wired
circuits. Each switch has an Off, Low, and High posi-
tion so that both the driver and the front seat pas-
senger can select a preferred seat heating mode.
Each switch has two Light-Emitting Diodes (LED)
which light to indicate that the heater for the seat is
turned on.
The heated seat switches and their LEDs cannot
be repaired. If either switch or LED is faulty or dam-
aged, the entire switch assembly must be replaced.
OPERATION
There are three positions that can be selected with
each of the heated seat switches: Off, Low, or High.
When the left side of the switch rocker is fully
RSHEATED SEAT SYSTEM8G-11
HEATED SEAT ELEMENT (Continued)
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AUTO SHUT DOWN RELAY
DESCRIPTION
The relay is located in the Power Distribution Cen-
ter (PDC). For the location of the relay within the
PDC, refer to the PDC cover for location. Check elec-
trical terminals for corrosion and repair as necessary
OPERATION
The ASD sense circuit informs the PCM when the
ASD relay energizes. A 12 volt signal at this input
indicates to the PCM that the ASD has been acti-
vated. This input is used only to sense that the ASD
relay is energized.
When energized, the ASD relay supplies battery
voltage to the fuel injectors, ignition coils and the
heating element in each oxygen sensor. If the PCM
does not receive 12 volts from this input after
grounding the ASD relay, it sets a Diagnostic Trouble
Code (DTC).
When energized, the ASD relay provides power to
operate the injectors, ignition coil, generator field, O2
sensor heaters (both upstream and downstream), and
also provides a sense circuit to the PCM for diagnos-
tic purposes. The PCM energizes the ASD any time
there is a Crankshaft Position sensor signal that
exceeds a predetermined value. The ASD relay can
also be energized after the engine has been turned
off to perform an O2 sensor heater test, if vehicle is
equipped with OBD II diagnostics.
As mentioned earlier, the PCM energizes the ASD
relay during an O2 sensor heater test. This test is
performed only after the engine has been shut off.
The PCM still operates internally to perform several
checks, including monitoring the O2 sensor heaters.
CAMSHAFT POSITION
SENSOR
DESCRIPTION
The camshaft position sensorfor the 3.3/3.8L is
mounted in the front of the timing case cover (Fig. 7)
and the camshaft position sensor for the 2.4L is
mounted on the end of the cylinder head (Fig. 4).
OPERATION
The camshaft position sensor provides cylinder
identification to the Powertrain Control Module
(PCM) (Fig. 2). The sensor generates pulses as
groups of notches on the camshaft sprocket pass
underneath it (Fig. 3). The PCM keeps track of
crankshaft rotation and identifies each cylinder by
the pulses generated by the notches on the camshaftsprocket. Four crankshaft pulses follow each group of
camshaft pulses.
When the PCM receives 2 cam pulses followed by
the long flat spot on the camshaft sprocket, it knows
that the crankshaft timing marks for cylinder 1 are
next (on driveplate). When the PCM receives one
camshaft pulse after the long flat spot on the
sprocket, cylinder number 2 crankshaft timing marks
are next. After 3 camshaft pulses, the PCM knows
cylinder 4 crankshaft timing marks follow. One cam-
shaft pulse after the 3 pulses indicates cylinder 5.
The 2 camshaft pulses after cylinder 5 signals cylin-
der 6 (Fig. 3). The PCM can synchronize on cylinders
1or4.
When metal aligns with the sensor, voltage goes
low (less than 0.3 volts). When a notch aligns with
the sensor, voltage switches high (5.0 volts). As a
group of notches pass under the sensor, the voltage
switches from low (metal) to high (notch) then back
to low. The number of notches determine the amount
of pulses. If available, an oscilloscope can display the
square wave patterns of each timing event.
Top Dead Center (TDC) does not occur when
notches on the camshaft sprocket pass below the cyl-
inder. TDC occurs after the camshaft pulse (or
pulses) and after the 4 crankshaft pulses associated
with the particular cylinder. The arrows and cylinder
call outs on Figure 4 represent which cylinder the
flat spot and notches identify, they do not indicate
TDC position.
REMOVAL - 2.4L
The camshaft position sensor is mounted to the
rear of the cylinder head.
(1) Remove the negative battery cable.
Fig. 2 Camshaft Position Sensor
1 - ELECTRICAL CONNECTOR
2 - O-RING
3 - PAPER SPACER
RSIGNITION CONTROL8I-3
ProCarManuals.com

INSTALLATION - 3.3/3.8L
(1) Install coil over studs on bracket.
(2) Install 2 bolts to ignition coil.
(3) Install 2 nuts to the ignition coil studs. Tighten
nuts and bolts.
(4) Connect the electrical connector to the ignition
coil.
(5) Install the ignition cables to the ignition coil.
(6) Reposition the Power steering reservoir. Slide
bracket over the mounting stud (Fig. 12).
(7) Install 2 bolts the Power steering reservoir to
intake manifold.
(8) Tighten the lower nut to stud on ignition coil
bracket.
(9) Install the throttle and speed control cables to
clip.
(10) Connect the negative battery cable.
KNOCK SENSOR
DESCRIPTION
The knock sensor threads into the cylinder block.
The knock sensor is designed to detect engine vibra-
tion that is caused by detonation.
OPERATION
When the knock sensor detects a knock in one of
the cylinders, it sends an input signal to the PCM. In
response, the PCM retards ignition timing for all cyl-
inders by a scheduled amount.Knock sensors contain a piezoelectric material
which constantly vibrates and sends an input voltage
(signal) to the PCM while the engine operates. As the
intensity of the crystal's vibration increases, the
knock sensor output voltage also increases.
The voltage signal produced by the knock sensor
increases with the amplitude of vibration. The PCM
receives as an input the knock sensor voltage signal.
If the signal rises above a predetermined level, the
PCM will store that value in memory and retard
ignition timing to reduce engine knock. If the knock
sensor voltage exceeds a preset value, the PCM
retards ignition timing for all cylinders. It is not a
selective cylinder retard.
The PCM ignores knock sensor input during engine
idle conditions. Once the engine speed exceeds a
specified value, knock retard is allowed.
Knock retard uses its own short term and long
term memory program.
Long term memory stores previous detonation
information in its battery-backed RAM. The maxi-
mum authority that long term memory has over tim-
ing retard can be calibrated.
Short term memory is allowed to retard timing up
to a preset amount under all operating conditions (as
long as rpm is above the minimum rpm) except WOT.
The PCM, using short term memory, can respond
quickly to retard timing when engine knock is
detected. Short term memory is lost any time the
ignition key is turned off.
NOTE: Over or under tightening affects knock sen-
sor performance, possibly causing improper spark
control.
REMOVAL - 2.4L
The knock sensor threads into the side of the cyl-
inder block in front of the starter (Fig. 13).
(1) Disconnect electrical connector from knock sen-
sor.
(2) Use a crow foot socket to remove the knock
sensors.
REMOVAL - 3.8L
The knock sensor threads into the side of the cyl-
inder block in the rear.
(1) Disconnect the negative battery cable.
(2) Raise vehicle and support.
(3) On All Wheel Drive vehicles remove the PTU
(Power Transfer Unit), refer to the Transmission sec-
tion for more information.
(4) Disconnect electrical connector from knock sen-
sor.
(5) Use a crow foot socket to remove the knock
sensor.
Fig. 12 IGNITION COIL BRACKET 3.3/3.8L
RSIGNITION CONTROL8I-7
IGNITION COIL (Continued)
ProCarManuals.com

LAMPS
TABLE OF CONTENTS
page page
LAMPS/LIGHTING - EXTERIOR............... 1LAMPS/LIGHTING - INTERIOR............... 17
LAMPS/LIGHTING - EXTERIOR
TABLE OF CONTENTS
page page
LAMPS/LIGHTING - EXTERIOR
DESCRIPTION............................2
OPERATION.............................2
DIAGNOSIS AND TESTING..................3
LAMPS/LIGHTING - EXTERIOR.............3
SPECIFICATIONS.........................7
BRAKE LAMP SWITCH
DESCRIPTION............................7
OPERATION.............................7
DIAGNOSIS AND TESTING..................7
BRAKE LAMP SWITCH...................7
REMOVAL...............................8
INSTALLATION............................8
CENTER HIGH MOUNTED STOP LAMP
REMOVAL...............................9
INSTALLATION............................9
CENTER HIGH MOUNTED STOP LAMP UNIT
REMOVAL...............................9
INSTALLATION............................9
FOG LAMP
REMOVAL...............................9
INSTALLATION............................9
FOG LAMP UNIT
REMOVAL..............................10
INSTALLATION...........................10
ADJUSTMENTS..........................10
HEADLAMP
REMOVAL..............................11
INSTALLATION...........................11HEADLAMP SWITCH
DIAGNOSIS AND TESTING.................11
HEADLAMP SWITCH....................11
REMOVAL..............................11
INSTALLATION...........................11
HEADLAMP UNIT
REMOVAL..............................12
INSTALLATION...........................12
ADJUSTMENTS..........................12
LICENSE PLATE LAMP
REMOVAL..............................14
INSTALLATION...........................14
MULTI-FUNCTION SWITCH
DESCRIPTION...........................14
OPERATION.............................15
DIAGNOSIS AND TESTING.................15
MULTI-FUNCTION SWITCH...............15
REMOVAL..............................15
INSTALLATION...........................15
PARK/TURN SIGNAL LAMP
REMOVAL..............................15
INSTALLATION...........................15
TAIL LAMP
REMOVAL..............................16
INSTALLATION...........................16
TAIL LAMP UNIT
REMOVAL..............................16
INSTALLATION...........................16
RSLAMPS8L-1
ProCarManuals.com

LAMPS/LIGHTING - EXTERIOR
DESCRIPTION
LAMP SYSTEMS
RS vehicles use lighting on the interior and exte-
rior of the vehicle for illuminating and indicating
purposes. Lighting circuits are protected by fuses.
Lighting circuits require an overload protected power
source, on/off device, lamps and body ground to oper-
ate properly. Plastic lamps require a wire in the har-
ness to supply body ground to the lamp socket.
Replace sockets and bulbs that are corroded.
Some of the interior and exterior lighting functions
are governed by the Body Control Module. The head-
lamp, dome, and the door ajar switches provide sig-
nals to the Body Control Module. The Body Control
Module in turn sends a J1850 message to the Front
Control Module (FCM) to enable the necessary driv-
ers to set the required illumination configuration.
Wire connectors can make intermittent contact or
become corroded. Before coupling wire connectors,
inspect the terminals inside the connector. Male termi-
nals should not be bent or disengaged from the insu-
lator. Female terminals should not be sprung open or
disengaged from the insulator. Bent and sprung termi-
nals can be repaired using needle nose pliers and pick
tool. Corroded terminals appear chalky or green. Cor-
roded terminals should be replaced to avoid recur-
rence of the problem symptoms.
Begin electrical system failure diagnosis by testing
related fuses in the fuse block and intelligent power
module. Verify that bulbs are in good condition and
test continuity of the circuit ground. Refer to the
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.
AUTOMATIC HEADLAMP SYSTEM
The Automatic Headlamp system turns the instru-
mentation and exterior illumination lamps ON when
the ambient light levels are Night and OFF when
light levels are Day.
DAYTIME RUNNING LAMPS
Operating the high-beam headlamps at reduced
power provides daytime running lamps, which are
required on all new Canadian vehicles.
HEADLAMPS ON WITH WINDSHIELD WIPERS
For vehicles equipped with the Automatic Head-
lamp System, the instrumentation and exterior illu-
mination lamps will be turned ON when theheadlamp switch is in the AUTO position, RPM >
450 and the windshield wipers have been in the
intermittent, low or high mode of operation for more
than ten seconds. When the windshield wipers are
turned OFF the Body Control Module will determine
if the instrumentation and exterior illumination
lamps should remain ON base upon the current
ambient light level.
HEADLAMP SYSTEM
The configuration of the headlamp system of head-
lamps, park lamps and fog lamps is determined by
the BCM. The BCM determines the lighting configu-
ration as a result of the inputs from the ignition
switch, headlamp switch and multifunction switch. A
J1850 is transmitted from the BCM to the FCM to
enable the necessary drivers to set the illumination
configuration. Four wires are connected between the
headlamp switch and the BCM. The first wire con-
tains information regarding the position of the head-
lamp switch (Off, Automatic Headlamps, Automatic
Headlamp switch fog, Park with Fog, Head, or Head
with Fog Lamps). The second wire contains informa-
tion regarding the position of the dimmer switch
(Dome Lamp, Daytime Brightness, Dimming Level or
Off). The third wire is a dedicated signal return
(ground) wire. The fourth wire provides power to the
front fog lamp indicator.
HEADLAMP TIME DELAY SYSTEM
The headlamp time delay system is controlled by
the Body Control Module (BCM) via a J1850 message
transmitted by the BCM to the FCM to turn off the
headlamps.
OPERATION
AUTOMATIC HEADLAMP SYSTEM
Automatic headlamps are controlled by the Body
Control Module (BCM). With the headlamp switch in
the AUTO position, the BCM will control the head-
lamp, parking, side marker, tail and instrumentation
lamps based on ambient light levels. Ambient light
levels are monitored by the BCM using the Day/
Night signal and Electrochromatic Mirror (ECM)
present from the Compass Mini Trip (CMTC) located
on the front windshield in front of the rear view mir-
ror (ECM). Ambient light readings are averaged to
limit cycling the lamps ON and OFF when passing
through areas with varying light levels. The auto-
matic headlamps will only function when the engine
is running with RPM > 450. When the headlamp
switch is in the AUTO position (Automatic mode), the
Headlamp Time Delay system will function when the
ignition switch is placed in any position other than
run/start.
8L - 2 LAMPS/LIGHTING - EXTERIORRS
ProCarManuals.com

DAYTIME RUNNING LAMPS
Power is reduced using pulse-width modulation to
the high beams, where by the power is switched on
and off rapidly instead of remaining on continuously.
The duration and interval of the power pulses is pro-
grammed into the Front Control Module (FCM).
HEADLAMP SYSTEM
The headlamp system will default to headlamps
ON position when ignition switch is ON and when an
open or short circuit failure occurs on the headlamp
switch input. The system will return to normal oper-
ation when the open or short is repaired. A fault will
be reported by the BCM when a failure occurs on the
dimmer or headlamp switch input.
If the exterior lamps are ON and the headlamp
switch is in any position other than OFF or AUTO
and with the ignition switch OFF (LOCK) after 3
minutes the BCM sends a message via J1850 to the
FCM informing the FCM to turn off the headlamps,
park lamps and fog lamps. This feature prevents the
vehicle battery from being discharged when the vehi-
cle lights have been left ON.
HEADLAMP TIME DELAY SYSTEM
The headlamp time delay system is activated by
turning the headlamps ON (high or low beam) while
the engine is running, turning the ignition switch
OFF, and then turning the headlamp switch OFF
within 45 seconds. The system will not activate if
more than 45 seconds elapse between ignition switch
OFF and headlamp switch OFF. The BCM will allow
the headlamps to remain ON for 90 seconds (config-
urable) before they automatically turn off (If the key
is in the ignition during the headlamp time delay
mode, then both the headlamps and park lamps
(including panel dimming) will be ON). Refer to the
Owner's Manual for more information.
If the headlamp switch is in the Auto Headlamp
Position, the headlamps are ON due to the night sig-
nal from the CMTC and the ignition switch is in any
position other than run/start, the BCM shall enter a
90 second (configurable) Auto Headlamps time delay
mode. If the key is in the ignition during the head-
lamp time delay mode, then both the headlamps and
park lamps (including panel dimming) will be ON. If
the key is not in the ignition, then only the head-
lamps will be ON. The BCM will allow the head-
lamps to remain ON for 90 seconds before they
automatically turn OFF. Refer to the Owner's Man-
ual for more information.
LAMP OUTAGE
If one or more of the following lamps (Low and/or
High beams) are out, then a ªlamps outº indicator
located in the cluster will illuminate.
OPTICAL HORN/HIGH BEAMS
When the multifunction switch is pulled to the first
detent (optical horn) signal, the headlamps are ON,
key-in the ignition the BCM shall send a message via
J1850 to the FCM to turn on the headlamps drivers
to illuminate all four filaments (Low and High
beams). When the multifunction switch is pulled to
the second detent (high beam) signal and the head-
lamps are ON, the BCM shall send a message via
J1850 to the FCM to turn on the headlamps drivers.
The High Beams are illuminated and the Low Beams
and Fog Lamps (if ON) are extinguished. If the head-
lamps were in the high beam configuration when
power was removed from the headlamps, the head-
lamps will be configured as low beam the next time
they are activated.
DIAGNOSIS AND TESTING
WARNING: EYE PROTECTION SHOULD BE USED
WHEN SERVICING GLASS COMPONENTS. PER-
SONAL INJURY CAN RESULT.
CAUTION: Do not touch the glass of halogen bulbs
with fingers or other possibly oily surface, reduced
bulb life will result. Do not use bulbs other than
those indicated in the Bulb Application table. Dam-
age to lamp and/or Daytime Running Lamp Module
can result. Do not use fuses, circuit breakers or
relays having greater amperage value than indi-
cated on the fuse panel or in the Owners Manual.
When a vehicle experiences problems with the
headlamp system, verify the condition of the battery
connections, fuses, charging system, headlamp bulbs,
wire connectors, relay, high beam switch, dimmer
switch, and headlamp switch. Refer to the appropri-
ate 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 connec-
tors, splices and grounds.
Each vehicle is equipped with various lamp assem-
blies. A good ground is necessary for proper lighting
operation. Grounding is provided by the lamp socket
when it comes in contact with the metal body, or
through a separate ground wire.
When changing lamp bulbs check the socket for
corrosion. If corrosion is present, clean it with a wire
brush.
When it is necessary to remove components to ser-
vice another, it should not be necessary to apply
excessive force or bend a component to remove it.
Before damaging a trim component, verify hidden
fasteners or captured edges are not holding the com-
ponent in place.
RSLAMPS/LIGHTING - EXTERIOR8L-3
LAMPS/LIGHTING - EXTERIOR (Continued)
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