2002 JEEP LIBERTY mirror controls

controls the ground for the heated seat switch indi-
cator lamps (LED's).
When a heated seat switch (Driver or Passenger) is
depressed a signal is received by the heated seat
module, the module energizes the proper indicator
LED (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 36É C (96.8É 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.
If the heated seat module detects a heated seat
sensor value input that is out of range or a shorted
or open heated seat element circuit, it will notify the
vehicle operator or the repair technician of this con-
dition by flashing the High and/or Low indicator
lamps in the affected heated seat switch. Refer to
Diagnosis and Testing Heated Seat Systemin
Heated Systems for flashing LED diagnosis and test-
ing procedures. Refer toDiagnosis and Testing
Heated Seat Modulein this section for heated seat
module diagnosis and testing procedures. Also refer
to the Body Diagnostic Manual for additional diagno-
sis and testing procedures.
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
toHeated Seat System Diagnosis and Testingin
Heated Systems for flashing LED failure identifica-
tion. Refer toWiring Diagramsin for complete
heated seat system wiring diagrams.
(1) Remove the heated seat module from its
mounting location (Refer to 8 - ELECTRICAL/ELEC-
TRONIC CONTROL MODULES/MEMORY HEATED
SEAT/MIRROR MODULE - REMOVAL).NOTE: ANY RESISTANCE VALUES (OHMSV) GIVEN
IN THE FOLLOWING TEXT ARE SUPPLIED USING
THE AUTOMATIC RANGE GENERATED BY A
FLUKETAUTOMOTIVE METER. IF ANOTHER TYPE
OF MEASURING DEVICE IS USED THE VALUES
GENERATED MAY NOT BE THE SAME AS THE
RESULTS SHOWN HERE, OR MAY HAVE TO BE
CONVERTED TO THE RANGE USED HERE.
RIGHT SEAT HEATER INOPERATIVE
(1) If a heated seat heats but one or both indicator
lamps (LED's) on the heated seat switch fail to illu-
minate, check the driver circuit with the inoperative
LED for a short to ground. If OK, replace the heated
seat switch. If NOT OK repair the short to ground as
required and than replace the heated seat switch.
NOTE: IF THE RIGHT SEAT CUSHION IS ALREADY
WARM THE FOLLOWING STEP WILL NOT PROVE
CONCLUSIVE.
(2) Back-probe the heated seat module wire har-
ness connector (Fig. 15), do not disconnect. Check
cavity #3 for battery voltage when the right heated
seat switch is turned ªONº, voltage should be
present, If OK go to Step 3 If NOT OK, test the right
heated seat switch (Refer to 8 - ELECTRICAL/
HEATED SEATS/PASSENGER HEATED SEAT
SWITCH - DIAGNOSIS AND TESTING). If the
switch tests OK, check for continuity between the
switch and control module on the MUX circuit, If OK
replace the heated seat control module. If NOT OK,
repair the open or shorted MUX circuit as required.
Fig. 15 Heated Seat Module Electrical Connector
8E - 22 ELECTRONIC CONTROL MODULESKJ
HEATED SEAT MODULE (Continued)

WINDOW DEFOGGER
TABLE OF CONTENTS
page page
WINDOW DEFOGGER
DESCRIPTION - REAR WINDOW DEFOGGER . . 3
OPERATION - REAR WINDOW DEFOGGER....3
DIAGNOSIS AND TESTING - REAR WINDOW
DEFOGGER SYSTEM...................4
STANDARD PROCEDURE - REAR GLASS
HEATING GRID REPAIR.................4
REAR WINDOW DEFOGGER GRID
DESCRIPTION..........................5
OPERATION............................5
DIAGNOSIS AND TESTING - REAR WINDOW
DEFOGGER GRID......................5
REAR WINDOW DEFOGGER RELAY
DESCRIPTION..........................6
OPERATION............................6DIAGNOSIS AND TESTING - REAR WINDOW
DEFOGGER RELAY.....................6
REMOVAL.............................7
INSTALLATION..........................7
REAR WINDOW DEFOGGER SWITCH
DESCRIPTION..........................8
OPERATION............................8
DIAGNOSIS AND TESTING
DIAGNOSIS AND TESTING - REAR
WINDOW DEFOGGER SWITCH...........8
DIAGNOSIS AND TESTING - REAR HVAC
CONTROL ASSEMBLY WINDOW
DEFOGGER FUNCTION.................9
REMOVAL.............................9
INSTALLATION..........................9
WINDOW DEFOGGER
DESCRIPTION - REAR WINDOW DEFOGGER
The rear window defogger system will only operate
when the ignition switch is in the run position. When
the defogger switch is in the run position, an electric
heater grid on the rear window glass is energized.
Vehicles with the heated mirror options also have
heater grids located behind the outside rear view
mirror glass. Each of these grids produce heat to help
clear the rear window glass and outside rear view
mirrors of ice, snow, or fog.
OPERATION - REAR WINDOW DEFOGGER
The rear window defogger system is controlled by a
switch installed with the HVAC control assembly. An
amber indicator lamp in the switch button will light
to indicate when the rear window defogger system is
turned on. The HVAC control head circuitry, which
contains the defogger system timer logic, monitors
the state of the defogger switch through a hard-wired
input. The instrument cluster circuitry controls therear window defogger system through a hard-wired
control output to the rear window defogger relay. The
rear window defogger timer and logic circuitry cannot
be adjusted or repaired and, if faulty or damaged, the
HVAC control head assembly must be replaced.
The rear window defogger system will be automat-
ically turned off after a programmed time interval of
about ten minutes. After the initial time interval has
expired, if the rear window defogger switch is turned
on again during the same ignition cycle, the defogger
system will automatically turn off after about five
minutes.
The rear window defogger system will automati-
cally shut off if the ignition switch is turned to the
Off position, or it can be turned off manually by
depressing the instrument panel switch. Following
are general descriptions of the major components in
the rear window defogger system. Refer to the own-
er's manual in the vehicle glove box for more infor-
mation on the features, use and operation of the
defogger system.
KJWINDOW DEFOGGER 8G - 3

mission have an illuminated transmission range indi-
cator integral to the console mounted gearshift
mechanism, and controlled by the panel lamps dim-
mer circuit.
²Vanity Lamps- Available single intensity van-
ity lamps are located on each side of a covered mirror
on both the right and left sun visors, and are con-
trolled by an integral vanity mirror cover-actuated
switch on the courtesy lamp circuit.
Other components of the interior lighting system
for this model include:
²Body Control Module- The Body Control
Module (BCM) is located on the Junction Block (JB)
under the driver side outboard end of the instrument
panel. (Refer to 8 - ELECTRICAL/ELECTRONIC
CONTROL MODULES/BODY CONTROL MODULE
- DESCRIPTION).
²Door Ajar Switches- A door ajar switch is
integral to the door latch mechanism of each front
and rear door.
²Flip-Up Glass Ajar Switch- A flip-up glass
ajar switch is integral to the flip-up glass latch mech-
anism on the top of the tailgate inner panel.
²Multi-Function Switch- The multi-function
switch is located on the top of the steering column,
just below the steering wheel. The multi-function
switch includes a left (lighting) control stalk and a
right (wiper) control stalk. The left control stalk is
dedicated to providing almost all of the driver con-
trols for both the exterior and interior lighting sys-
tems. (Refer to 8 - ELECTRICAL/LAMPS/LIGHTING
- EXTERIOR/MULTI-FUNCTION SWITCH -
DESCRIPTION).
²Tailgate Ajar Switch- A tailgate ajar switch is
integral to the latch mechanism of the tailgate.
Hard wired circuitry connects the interior lighting
system components to the electrical system of the
vehicle. These hard wired circuits are integral to sev-
eral wire harnesses, which are routed throughout the
vehicle and retained by many different methods.
These circuits may be connected to each other, to the
vehicle electrical system and to the interior lighting
system components through the use of a combination
of soldered splices, splice block connectors, and many
different types of wire harness terminal connectors
and insulators. Refer to the appropriate wiring infor-
mation. The wiring information includes wiring dia-
grams, proper wire and connector repair procedures,
further details on wire harness routing and reten-
tion, as well as pin-out and location views for the
various wire harness connectors, splices and grounds.
OPERATION
The interior lighting systems can be divided into
two general classifications based upon the circuit
that controls their operation: The courtesy lamp cir-cuit, or the panel lamps dimmer circuit. Following
are paragraphs that briefly describe the operation of
each of the major interior lighting systems. The hard
wired circuits and components of the interior lighting
systems may be diagnosed and tested using conven-
tional diagnostic tools and procedures. However, con-
ventional diagnostic methods may not prove
conclusive in the diagnosis of the Body Control Mod-
ule (BCM), the ElectroMechanical Instrument Clus-
ter (EMIC), or the Programmable Communications
Interface (PCI) data bus network. The most reliable,
efficient, and accurate means to diagnose the BCM,
the EMIC, and the PCI data bus network inputs and
outputs related to the various interior lighting sys-
tems requires the use of a DRBIIItscan tool. Refer
to the appropriate diagnostic information.
COURTESY LAMP CIRCUIT Depending upon the
selected vehicle options the courtesy lamp circuit
may include the courtesy lamps located below the
instrument panel, the dome or map/reading lamps
located in the headliner near the windshield, the
cargo lamp located in the headliner near the rear
roof header, and the vanity lamps located in the sun
visors. The lamps in the courtesy lamp circuit are
provided with battery current at all times from a
fused B(+) fuse in the Junction Block (JB) through a
fused B(+) circuit. The Body Control Module (BCM)
controls the ground path for these lamps using an
internal driver through the courtesy lamp driver cir-
cuit based upon hard wired inputs from the door ajar
switches, the flip-up glass ajar switch, and the tail-
gate ajar switch. After all of the ajar switch inputs to
the BCM transition to open, the BCM will keep the
lamps illuminated for about 27 seconds, then fade
the lamps to off (theater dimming) over about three
seconds.
The BCM also provides courtesy lamp operation
based upon a resistor multiplexed input from the
interior lighting control ring on the left (lighting)
control stalk of the multi-function switch through the
headlamp switch mux circuit, and in response to cer-
tain inputs from the optional Remote Keyless Entry
(RKE) system. A resistor multiplexed courtesy lamp
defeat input from the control ring on the left (light-
ing) control stalk of the multi-function switch will
cause the BCM to override normal courtesy lamp
operation based upon inputs from all of the ajar
switches. A hard wired input from the courtesy lamp
defeat switch in the optional cargo lamp through a
rear courtesy lamp control circuit will cause the BCM
to override normal courtesy lamp operation based
upon inputs from only the flip-up glass and tailgate
ajar switches.
For those lamps on the courtesy lamp circuit with
independent switching, such as the optional reading
lamps and vanity lamps, the BCM provides a ground
KJLAMPS/LIGHTING - INTERIOR 8L - 67
LAMPS/LIGHTING - INTERIOR (Continued)