fuse CHRYSLER CARAVAN 2005 Owner's Manual
Page 362 of 2339
CONDITION POSSIBLE CAUSE CORRECTION
(6) CLOCKSPRING
INOPERATIVE.(6) REPLACE CLOCKSPRING.
(7) FRONT CONTROL
MODULE INOPERATIVE.(7) REFER TO ELECTRONIC CONTROL
MODULES/FRONT CONTROL MODULE.
FUSE BLOWS WHEN HORN SOUNDS (1) SHORT CIRCUIT IN
HORN OR HORN WIRING.(1) REMOVE HORN RELAY, CHECK
FOR SHORTED HORN OR HORN
WIRING. DISCONNECT HORN WIRE
HARNESS TO ISOLATE SHORT AND
REPAIR AS NECESSARY.
(2) CLOCKSPRING
INOPERATIVE.(2) REPLACE CLOCKSPRING.
FUSE BLOWS WITHOUT BLOWING
HORN(1) SHORT CIRCUIT. (1) REMOVE RELAY, INSTALL NEW
FUSE, IF FUSE DOES NOT BLOW
REPLACE HORN RELAY. IF FUSE
BLOWS WITH RELAY REMOVED,
CHECK FOR SHORT TO GROUND
WITH OHMMETER ON CIRCUIT
BETWEEN TERMINALS 30 & 86 AND
THE FUSE TERMINAL. REPAIR AS
NECESSARY.
(2) CLOCKSPRING
INOPERATIVE.(2) REPLACE CLOCKSPRING.
HORN
DIAGNOSIS AND TESTING
HORN
HORN
(1) Disconnect wire connector at horn.
(2) Using a voltmeter, connect one lead to ground
terminal and the other lead to the positive wire ter-
minal (Fig. 1).
(3) Depress the horn switch, battery voltage
should be present.
(4) If no voltage, refer toHORNS WILL NOT
SOUND. If voltage is OK, go to step Step 5.
(5) Using ohmmeter, test ground wire for continu-
ity to ground.
(6) If no ground repair as necessary.
(7) If wires test OK and horn does not sound,
replace horn.
HORNS SOUND CONTINUOUSLY
CAUTION: Continuous sounding of horns may
cause relay to fail.
The horn switch (membrane) sometimes can be the
cause without the switch being depressed.(1) Remove the horn relay from the intelligent
power module.
(2)
Using a continuity tester, test continuity from the
X3 cavity of the horn relay to ground. 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.
(a)If continuity is detected, proceed to step Step 3.
(b) If NO continuity, replace the horn relay.
(3) Remove the airbag trim cover from the steering
wheel and disengage horn connector.
(4) Install horn relay into Integrated Power Mod-
ule (IPM).
(a)
If horn does not sound, replace airbag trim
cover.
(b) If horn sounds, repair grounded X3 circuit
from IPM to clockspring in the steering column.
HORNS WILL NOT SOUND
Check horn fuse#8intheIPM. If fuse is blown,
check for a shorted switch in the airbag module. and
refer to FUSE BLOWN section. If fuse is OK, refer to
FUSE OK section.
FUSE BLOWN
(1) Verify condition of battery terminals and volt-
age, (Refer to 8 - ELECTRICAL/BATTERY SYSTEM
RSHORN8H-3
HORN SYSTEM (Continued)
Page 363 of 2339
- DIAGNOSIS AND TESTING). If battery connec-
tions and battery charge is OK proceed to Step 2.
(2) Using a voltmeter, test for battery voltage at
both sides of horn fuse 7. If voltage is OK, on both
sides of fuse, proceed to Fuse OK. If voltage is OK,
on one side of fuse, the fuse is blown, proceed to Step
3.
(3) Using a suitable ammeter in place of the fuse,
test amperage draw of the horn circuit. If amperage
draw is greater than 20 amps without the horn
switch depressed, a grounded circuit exists between
the fuse and the horn relay. Proceed to Step 4. If
amperage draw is greater than 20 amps with the
horn switch depressed, a grounded circuit exists
between the horn relay and the horn. Proceed to step
Step 5.
(4) Remove the horn relay from the IPM. If the
amperage draw drops to 0 amps, the horn switch or
circuit is shorted. If the amperage draw does not
drop to 0 amps, repair short at the IPM.
(5) Disengage a wire connector from one of the
horns. If amperage drops and the connected horn
sounds, replace the faulty horn. If amperage does not
drop with both horns disconnected and the horn
switch depressed, proceed to Step 6.
(6) Using a continuity tester, with the horns dis-
connected test continuity of the X2 cavity of the horn
relay to ground. If continuity is detected, the circuit
is grounded between the Junction Block and the
horns. Locate and repair pinched harness.
FUSE OK
(1) Remove the horn relay from the intelligent
power module.
(2) Using a continuity tester, Depress horn switch
and test continuity from the X3 cavity of the horn
relay to ground.
(a) If continuity is detected, proceed to Step 3.
(b) If NO continuity, proceed to Step 4.
(3) Using a suitable jumper wire, jump across the
fuse F62 cavity and the X2 cavity of the horn relay in
the Junction Block.
(a) If the horn sounds, replace the horn relay.
(b) If the horn does not sound, proceed to Step 4.
(4) Remove airbag trim cover from steering wheel.
Refer to ELECTRICAL, RESTRAINTS.
(5) Test continuity across horn switch connectors
with horn switch depressed.
(a) If continuity is detected, repair open circuit
between the relay and the horn switch.
(b) If NO continuity, replace airbag trim cover.
(6) Install horn relay into intelligent power mod-
ule.
(7) Disengage wire connectors from horns.(8) Using a voltmeter, with the horn switch
depressed test voltage across horn connector termi-
nals of the wire harness (Fig. 1).
(a) If voltage is detected, replace horns.
(b) If NO voltage, proceed to step Step 9.
(9) With the horn switch depressed, test for volt-
age between the X2 circuit and ground.
(a) If voltage OK, repair system ground at right
cowl area.
(b) If NO voltage, repair open X2 circuit between
the relay and the horns.
REMOVAL
(1) Disconnect and isolate the battery negative
cable.
(2) Hoist and support the front of the vehicle on
safety stands.
(3) From behind the front fascia and forward of
the left front wheel, disconnect the wire connectors
from horn.
(4) Remove the mounting bracket attaching nut
from the bottom of radiator closure panel. Do not
remove the horn from mounting bracket.
(5) Separate the horn(s) from vehicle.
INSTALLATION
(1) Install the horns to the vehicle.
(2) Install the mounting bracket fastener.
(3) Reconnect the wire connectors to the horns.
(4) Lower the vehicle.
(5) Reconnect the battery negative cable.
HORN SWITCH
DESCRIPTION
The horn switch is molded into the airbag trim
cover. The horn switch can not be serviced separately.
For service procedures (Refer to 8 - ELECTRICAL/
RESTRAINTS/AIRBAG COVER - REMOVAL).
Fig. 1 Horn Connector
8H - 4 HORNRS
HORN (Continued)
Page 387 of 2339
LAMPS/LIGHTING - EXTERIOR
DESCRIPTION
LAMP SYSTEMS
Lighting circuits are protected by fuses. Lighting
circuits require an overload protected power and high
side drivers source, ON/OFF device, lamps and body
grounds to operate properly. Plastic lamps require a
wire in the harness to supply body ground to the
lamp socket. Replace sockets and bulbs that are cor-
roded.
Some of the interior and exterior lighting functions
are governed by the Body Control Module (BCM).
The headlamp, dome, and the door ajar switches pro-
vide signals to the BCM. The BCM in turn sends a
Programmable Communication Interface (PCI) bus
message to the Front Control Module (FCM) to
enable the necessary drivers to set the required illu-
mination configuration.
Wire connectors can make intermittent contact or
become corroded. Before coupling wire connectors,
inspect the terminals inside the connector. Male ter-
minals should not be bent or disengaged from the
insulator. Female terminals should not be sprung
open or disengaged from the insulator. Bent and
sprung terminals can be repaired using needle nose
pliers and pick tool. Corroded terminals appear
chalky or green. Corroded terminals should be
replaced to avoid recurrence of the problem symp-
toms.
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.
AUTOMATIC HEADLAMP SYSTEM
The Automatic Headlamp system turns the instru-
mentation and exterior illumination lamps ON when
the ambient light levels are Night and the engine
RPM is 450 or above, 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. Daytime run-
ning lamps are functional when 450 rpm's are
reached.
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 the
headlamp 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 multi-function switch. A
PCI bus 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 PCI bus mes-
sage 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
Page 388 of 2339
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 FCM. Daytime running lamps are
functional when 450 rpm's are reached.
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 or PCI data bus communication between
the BCM and the FCM fails. The system will return
to normal operation 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 PCI bus to
the FCM informing the FCM to turn off the head-
lamps, park lamps and fog lamps. This feature pre-
vents the vehicle battery from being discharged when
the vehicle 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.
OPTICAL HORN/HIGH BEAMS
When the multi-function switch is pulled to the
first detent (optical horn) signal, the headlamps are
ON, key-in the ignition the BCM shall send a mes-
sage via PCI bus to the FCM to turn on the head-
lamps drivers to illuminate all four filaments (Low
and High beams). When the multi-function switch is
pulled to the second detent (high beam) signal and
the headlamps are ON, the BCM shall send a mes-
sage via PCI bus to the FCM to turn on the head-
lamps drivers. The High Beams are illuminated and
the Low Beams and Fog Lamps (if ON) are extin-
guished. If the headlamps were in the high beam
configuration when power was removed from the
headlamps, the headlamps will be configured as low
beam the next time they are activated.
NOTE: For RG - Export vehicles, the low beams and
front fog lamps will remain ON when high beams
are activated.
WARNING
Eye protection should be used when servicing
glass components. Personal injury or death can
result.
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. Damage to lamp and/or Daytime Running
Lamp Module can result. Do not use fuses, cir-
cuit breakers or relays having greater amper-
age value than indicated on the fuse panel or in
the Owners Manual.
Do not use bulbs other than those listed in
the Bulb Application Table. Damage to lamp
can result. Do not touch halogen bulbs with fin-
gers or other oily surfaces. Bulb life will be
reduced.
SPECIFICATIONS
EXTERIOR LAMPS
BULB APPLICATION TABLE
LAMP BULB
BACK-UP 3057
CHMSL 921
FRONT SIDE MARKER/PARK/
TURN (DODGE)3157A
FRONT SIDE MARKER/PARK/
TURN (CHRYSLER)3157AK
RSLAMPS/LIGHTING - EXTERIOR8L-3
LAMPS/LIGHTING - EXTERIOR (Continued)
Page 392 of 2339
(3) Install the retaining screws.
(4) Reconnect the battery negative cable.
FRONT FOG LAMP
DIAGNOSIS AND TESTING - FRONT FOG LAMP
When a vehicle experiences problems with the
front fog lamp system, verify the condition of the bat-
tery connections, fuses, charging system, fog lamp
bulbs, wire connectors, relay, high beam switch, and
headlamp switch. Refer to the appropriate wiring
information.
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.
FRONT FOG LAMP DIAGNOSIS
CONDITION POSSIBLE CAUSES CORRECTION
FOG LAMPS ARE DIM
WITH ENGINE IDLING
OR IGNITION TURNED
OFF.1. Loose or corroded battery
cables.1. Clean and secure battery cable clamps and
posts.
2. Loose or worn generator drive
belt.2. Adjust or replace generator drive belt.
3. Charging system output too low. 3. Test and repair charging system. Refer to
Electrical, Charging,
4. Battery has insufficient charge. 4. Test battery state-of-charge. Refer to
Electrical, Battery System.
5. Battery is sulfated or shorted. 5. Load test battery. Refer to Electrical, Battery
System.
6. Poor lighting circuit Z349/Z248
ground.6. Test for voltage drop across Z349/248
ground locations. Refer to Electrical, Wiring
Information.
FOG LAMP BULBS
BURN OUT
FREQUENTLY1. Charging system output too
high.1. Test and repair charging system. Refer to
Electrical, Charging.
2. Loose or corroded terminals or
splices in circuit.2. Inspect and repair all connectors and splices.
Refer to Electrical, Wiring Information.
Fig. 7 CHMSL ELECTRICAL CONNECTOR
1 - CHMSL UNIT
2 - CHMSL ELECTRICAL CONNECTOR
RSLAMPS/LIGHTING - EXTERIOR8L-7
CENTER HIGH MOUNTED STOP LAMP UNIT (Continued)
Page 393 of 2339
CONDITION POSSIBLE CAUSES CORRECTION
FOG LAMPS ARE DIM
WITH ENGINE
RUNNING ABOVE IDLE1. Charging system output too low. 1. Test and repair charging system. Refer to
Electrical, Charging.
2. Poor lighting circuit Z349/Z248
ground.2. Test for voltage drop across Z349/Z248
ground locations. Refer to Electrical, Wiring
Information.
3. High resistance in fog lamp
circuit.3. Test amperage draw of fog lamp circuit.
FOG LAMPS FLASH
RANDOMLY1. Poor lighting circuit Z349/Z248
ground.1. Test for voltage drop across Z349/Z248
ground locations. Refer to Electrical, Wiring
Information.
2. Variable resistance in fog lamp
circuit.2. Test amperage draw of fog lamp circuit.
3. Faulty fog lamp switch (part of
headlamp switch).3. Replace headlamp switch.
4. Loose or corroded terminals or
splices in circuit.4. Inspect and repair all connectors and splices.
Refer to Electrical, Wiring Information.
5. Is relay engaging properly? 5. Verify function of fog lamp relay in IPM.
6. PCI Bus Communication. 6. Verify PCI bus message (fog lamp info)
transmitted from BCM and received by FCM.
FOG LAMPS DO NOT
ILLUMINATE1. Blown fuse for fog lamp. 1. Replace fuse. Refer to Electrical, Wiring
Information.
2. No Z349/Z248 ground at fog
lamps.2. Repair circuit ground. Refer to Electrical,
Wiring Information.
3. Faulty fog lamp switch (part of
headlamp switch).3. Replace headlamp switch.
4. Broken connector terminal or
wire splice in fog lamp circuit.4. Repair connector terminal or wire splice.
5. Faulty or burned out bulb. 5. Replace bulb.
6. Is relay engaging? 6. Verify function of fog lamp relay in IPM.
7. PCI Bus Communication. 7. Verify PCI bus message (fog lamp info)
transmitted from BCM and received by FCM.
REMOVAL
(1) Disconnect and isolate the battery negative
cable.
(2) From behind the bumper fascia, twist bulb
counter-clockwise, and remove bulb.
(3) Remove the wire connector from the fog lamp
bulb.
INSTALLATION
(1) Reconnect wire harness to bulb.
(2) Install bulb and twist clockwise.
(3) Install battery negative cable.
8L - 8 LAMPS/LIGHTING - EXTERIORRS
FRONT FOG LAMP (Continued)
Page 396 of 2339
HEADLAMP
DIAGNOSIS AND TESTING - HEADLAMP
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.
Each vehicle is equipped with various lamp assem-
blies. A good ground is necessary for proper lighting
operation. Grounding is provided by the lamp socketwhen 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.
HEADLAMP DIAGNOSIS
CONDITION POSSIBLE CAUSES CORRECTION
HEADLAMPS ARE DIM
WITH ENGINE IDLING
OR IGNITION TURNED
OFF.1. Loose or corroded battery
cables.1. Clean and secure battery cable clamps and
posts.
2. Loose or worn generator drive
belt.2. Adjust or replace generator drive belt.
3. Charging system output too low. 3. Test and repair charging system, refer to
Electrical, Charging
4. Battery has insufficient charge. 4. Test battery state-of-charge, refer to
Electrical, Battery System.
5. Battery is sulfated or shorted. 5. Load test battery, refer to Electrical, Battery
System.
6. Poor lighting circuit Z343/Z344-
ground.6. Test for voltage drop across Z343/Z344-
ground locations, refer to Electrical, Wiring
Diagram Information.
HEADLAMP BULBS
BURN OUT
FREQUENTLY.1. Integrated Power Module (IPM)
not controlling voltage.1. Test and repair Integrated Power Module.
2. Loose or corroded terminals or
splices in circuit.2. Inspect and repair all connectors and splices.
Refer to Electrical, Wiring Information.
HEADLAMPS ARE DIM
WITH ENGINE
RUNNING ABOVE IDLE.1. Charging system output too low. 1. Test and repair charging system, refer to
Electrical, Wiring Information.
2. Poor lighting circuit Z343/Z344-
ground.2. Test for voltage drop across Z343/Z344-
ground locations, refer to Electrical, Wiring
Information.
3. High resistance in headlamp
circuit.3. Test amperage draw of headlamp circuit.
RSLAMPS/LIGHTING - EXTERIOR8L-11
Page 412 of 2339
The compass unit will also compensate for magne-
tism the vehicle may acquire during normal use.
However, avoid placing anything magnetic directly on
the roof of the vehicle. Magnetic mounts for an
antenna, a repair order hat, or a funeral procession
flag can exceed the compensating ability of the com-
pass unit if placed on the roof panel. The use of mag-
netic tools on the fasteners that hold the overhead
console assembly to the roof header can also affect
compass operation. If the compass operation is
erratic and roof magnetization is suspected (Refer to
8 - ELECTRICAL/OVERHEAD CONSOLE - STAN-
DARD PROCEDURE - COMPASS DEMAGNETIZ-
ING).
DESCRIPTION - TEMPERATURE
All overhead consoles include temperature informa-
tion. The temperature displays the outside ambient
temperature in whole degrees. The temperature dis-
play can be toggled from Fahrenheit to Celsius by
selecting the desired U.S./Metric option from the cus-
tomer programmable features. The displayed temper-
ature is not an instant reading of conditions, but an
average temperature. It may take the temperature
display several minutes to respond to a major tem-
perature change, such as driving out of a heated
garage into winter temperatures.
When the ignition switch is turned to the Off posi-
tion, the last displayed temperature reading stays in
the electronic control modules (CMTC, EVIC) mem-
ory. When the ignition switch is turned to the On
position again, the electronic module will display the
memory temperature for one minute; then update the
display to the current average temperature reading
within five minutes.
The temperature function is supported by an ambi-
ent temperature sensor. The sensor is mounted near
the front and center of the vehicle, and is hard wired
to the Powertrain Control Module (PCM). The PCM
sends temperature status messages to the module
over the Programmable Communication Interface
(PCI) data bus circuit.
DIAGNOSIS AND TESTING
OVERHEAD CONSOLE
Any diagnosis of the overhead console should
begin with the use of the DRB IIItdiagnostic
tool. For information on the use of the DRB
IIIt, refer to the appropriate Diagnostic Proce-
dures information.If the problem with the overhead console is an
inaccurate or dashed (- -) display, refer to SELF-DI-
AGNOSTIC TEST. If the problem with the overhead
console is incorrect Vacuum Fluorescent Display
(VFD) dimming levels, use a DRB IIItscan tool and
the proper diagnostic procedures information to test
for the correct dimming message inputs being
received from the Body Control Module (BCM) or
Front Control Module (FCM) over the Programmable
Communications Interface (PCI) data bus circuit. If
the problem is a no-display condition, use the follow-
ing procedures.
Inspect the related wiring harness connectors for
broken, bent, pushed out, or corroded terminals.
Refer to the appropriate wiring information.
(1) Check the fused B(+) fuse in the integrated
power module. If OK, go to Step 2. If not OK, repair
the shorted circuit or component as required and
replace the faulty fuse.
(2) Check for battery voltage at the fused B(+) fuse
in the integrated power module. If OK, go to Step 3.
If not OK, repair the open fused B(+) circuit to the
fused B(+) fuse in the integrated power module as
required.
(3) Check the fused ignition switch output (run/
start) fuse in the integrated power module. If OK, go
to Step 4. If not OK, repair the shorted circuit or
component as required and replace the faulty fuse.
(4) Turn the ignition switch to the On position.
Check for battery voltage at the fused ignition switch
output (run/start) fuse in the integrated power mod-
ule. If OK, go to Step 5. If not OK, repair the open
fused ignition switch output (run/start) circuit to the
ignition switch as required.
(5) Turn the ignition switch to the Off position.
Disconnect and isolate the battery negative cable.
Remove the overhead console. Check for continuity
between the ground circuit cavity of the roof wire
harness connector for the electronics module and a
good ground. There should be continuity. If OK, go to
Step 6. If not OK, repair the open ground circuit as
required.
(6) Connect the battery negative cable. Check for
battery voltage at the fused B(+) circuit cavity of the
roof wire harness connector for the electronics mod-
ule. If OK, go to Step 7. If not OK, repair the open
fused B(+) circuit to the fused B(+) fuse in the inte-
grated power module as required.
(7) Turn the ignition switch to the On position.
Check for battery voltage at the fused ignition switch
output (run/start) circuit cavity of the roof wire har-
ness connector for the electronics module. If OK,
refer to SELF-DIAGNOSTIC TEST. If not OK, repair
the open fused ignition switch output (run/start) cir-
cuit to the fuse in the integrated power module as
required.
RSOVERHEAD CONSOLE8M-3
OVERHEAD CONSOLE (Continued)
Page 425 of 2339
POWER LIFTGATE SYSTEM
DESCRIPTION
the components of the power liftgate system are:
²Liftgate gear motor assembly
²Latch assembly
²Lift gear and rod
²Power liftgate control module
²Chime/thermistor
²Full open switch
²Engage actuator
²Pinch sensor
²Liftgate handle switch
²Overhead console switch
²Key fob switches (Fig. 1)
²Pawl switch
²Ratchet switch
The power liftgate system has its own power lift-
gate control module, located on the vehicles left body
D-pillar behind the trim panel. The power liftgate
gear motor assembly is located just above the control
module. The latch assembly is located in the bottom
center of the power liftgate, below the exterior lift-
gate handle switch. The power liftgate full open
switch, engage actuator, lift gear and rod are part of
the liftgate gear motor assembly. The pawl and
ratchet switches are part of the latch assembly. The
pinch sensors are located along the right and left
sides of the power liftgate, just above the body line.The liftgate handle switch is a power release switch
and is located in the rear light bar assembly, just
above the license plate. The overhead console switch
is a power open and close command switch located in
the vehicles overhead console.
Software technology has enabled the power liftgate
control module to detect resistance to liftgate travel,
which allows the power liftgate to stop and reverse
direction anytime an obstruction is felt or any of the
command switches are operated (only in closing
direction). Battery voltage is supplied to the power
liftgate system through a 40 amp fuse, located in the
Integrated Power Module (IPM) assembly. If the
power liftgate system develops a fault, the power lift-
gate can still be operated manually with a key, sim-
ilar to a manual liftgate.
The power liftgate control module communicates
on the Programmable Communication Interface (PCI)
Bus Circuit. Therefore, the power liftgate control
module can generate and store its own Diagnostic
Trouble Codes (DTC). The vehicles Body Control
Module (BCM) receives and supplies messages to the
power liftgate control module via the PCI bus circuit.
A diagnostic scan tool, such as the DRB IIItor equiv-
alent, is used to read and troubleshoot these DTCs.
Refer to the Body Diagnostic Manual for a complete
list of diagnostic routines.
For additional information, (Refer to 8 - ELECTRI-
CAL/POWER DOORS - OPERATION). Refer to the
appropriate wiring information for complete circuit
schematic or connector pin-out information.
WARNING: BE CERTAIN TO READ ALL WARNINGS
AND CAUTIONS BEFORE ATTEMPTING ANY SER-
VICE OF THE POWER LIFTGATE SYSTEM OR COM-
PONENTS.
OPERATION
With the push of a power liftgate open/close com-
mand switch (key fob or overhead console mounted) a
signal is sent out on the Programmable Communica-
tion Interface (PCI) Data Bus circuit. This signal is
detected at the Body Control Module (BCM). The
BCM then sends a signal out on the PCI Data Bus
circuit to the power liftgate control module. The
power liftgate control module then signals the power
liftgate motor to start an open or close cycle, depend-
ing on what position the liftgate is in.
During a liftgate open or close cycle, if the power
liftgate module detects sufficient resistance to liftgate
travel, such as an obstruction in the path of the lift-
gate, the power liftgate control module will immedi-
ately stop the liftgate movement and reverse travel
to the full open or closed position. The ability for the
power liftgate module to detect resistance to liftgate
Fig. 1 KEY FOB
1 - LEFT SLIDING DOOR SWITCH
2 - RIGHT SLIDING DOOR SWITCH
3 - LIFTGATE SWITCH
8N - 2 POWER LIFTGATE SYSTEMRS
Page 427 of 2339
LIFTGATE SYSTEM DIAGNOSIS
CONDITION POSSIBLE CAUSES CORRECTION
Liftgate opens unexpectedly Inoperative Power Liftgate Module or
Body Control Module (BCM)Disconnect then reconnect the battery
negative cable to reset module. Cycle the
power liftgate, if the power liftgate is still
not operating properly check for loose wire
connections, refer to the appropriate
diagnostic information
Inoperative latch assembly Check for blown fuse and loose wiring
connections
Check for Diagnostic Trouble Codes
(DTCs), replace latch as necessary
Inoperative open/close command
switchCheck for shorted or inoperative switch.
Replace switch as necessary
Liftgate will not open from
outside of vehicle manuallyInoperative key cylinder assembly Check for inoperative key cylinder
assembly. Replace key cylinder as
necessary
Check link rod connections at the latch and
key cylinder assembly
Check for binds or kinks in link rod
Check for foreign matter preventing the
operation of key cylinder assembly
Replace the components as necessary
Inoperative latch assembly Check for blown fuse and loose wiring
connections
Check for foreign matter preventing the
operation of latch assembly
Replace latch assembly as necessary
Binding or sticking of components Check for foreign matter preventing the
operation of door
Establish location of binding
Replace the components as necessary
Liftgate will not open/close
under powerInoperative Power Liftgate Module or
BCMDisconnect then reconnect the battery
negative cable to reset module. Cycle the
power liftgate, if the power liftgate is still
not operating properly check for loose wire
connections, refer to the appropriate
diagnostic information
Inoperative latch assembly Check for blown fuse and loose wiring
connections
Check for foreign matter preventing the
operation of latch assembly
Refer to the appropriate diagnostic
information. Replace latch assembly as
necessary
8N - 4 POWER LIFTGATE SYSTEMRS
POWER LIFTGATE SYSTEM (Continued)