Jeep 1996 Grand Cherokee Service Manual page 628

ZJ
DESCRIPTION AND OPERATION
COURTESY LAMPS, CARGO LAMP, IGNITION
SWITCH KEY-IN HALO LAMP . . . . . . . . . . . . . . 1
DAY/NIGHT MIRROR . . . . . . . . . . . . . . . . . . . . . . 2
GLOVE BOX LAMP . . . . . . . . . . . . . . . . . . . . . . . 2
ILLUMINATION LAMPS . . . . . . . . . . . . . . . . . . . . 1
INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . 1
DESCRIPTION AND OPERATION
INTRODUCTION
The Body Control Module (BCM) controls the cour-
tesy lamps and rear cargo lamps. The reading dome/
reading lamps in the overhead console act as
courtesy lamps as well as containing a switch for
independent operation.
Circuit 707 from the dimmer switch circuitry in
the head lamp switch provides the illumination lamp
intensity signal to the BCM. The BCM powers the
illumination lamps on circuit E2.
When the ignition switch is in the START or RUN
position, it connects circuit A1 from fuse 8 in the
PDC to circuit A21. Circuit A21 powers circuit F99
through PDC fuse 15. Circuit F99 feeds the BCM.
In the ACCESSORY or RUN position, the ignition
switch connects circuit A1 to circuit A31. Circuit A31
powers circuit V23 through fuse 3 in the junction
block. Circuit V23 feeds the BCM.
ILLUMINATION LAMPS
When the headlamps or parking lamps are ON, the
The Body Control Module (BCM) recieves the park
lamp input on circuit L90 and the illumination lamp
intensity signal on circuit 707. Circuit 707 from the
dimmer switch circuitry in the head lamp switch pro-
vides the illumination lamp intensity signal to the
BCM.
After calculating the requested illumination lamp
intesity, the BCM powers the following illumination
lamps on circuit E2:
• Headlamp switch
• Floor console
• Instrument panel
• Ash receiver
• Graphic Display or Vehicle Information Center
(VIC)
• Cigar lighter
• Radio
8W - 44 INTERIOR LIGHTING
8W-44 INTERIOR LIGHTING
INDEX
page
OVERHEAD CONSOLE LAMPS . . . . . . . . . . . . . . 2
UNDERHOOD LAMP . . . . . . . . . . . . . . . . . . . . . . 2
UNIVERSAL GARAGE DOOR OPENER . . . . . . . . 2
VISOR VANITY MIRRORS . . . . . . . . . . . . . . . . . . 2
SCHEMATICS AND DIAGRAMS
WIRING DIAGRAM INDEX . . . . . . . . . . . . . . . . . . 2
• A/C-Heater control switch
Circuit Z1 provides ground for the floor console
lamps, instrument panel lamps, ash receiver lamp,
graphic display or VIC. Circuit Z4 grounds the auto-
matic temperature control switch lamp. Circuit Z5
grounds the radio lamp. The cigar lighter lamp and
A/C-Heater control switch lamp (manual A/C-Heater)
are case grounded.
COURTESY LAMPS, CARGO LAMP, IGNITION
SWITCH KEY-IN HALO LAMP
When the courtesy lamp switch closes, it connects
circuit M11 from the Body Control Module to ground
on circuit Z1. In response the to the courtesy lamp
signal, the BCM energizes the courtesy lamp relay by
grounding the relay coil on circuit M112. When the
relay energizes, it connects circuit M2 to ground on
circuit Z1. Circuit M2 provides ground for the right
and left courtesy lamps, dome/reading lamps, key-in
halo lamp and cargo lamp.
Circuit A7 from fuse 15 in the Power Distribution
Center (PDC) powers circuit M1 through fuse 16 in
the junction block. Circuit M1 powers the right and
left courtesy lamps, ignition switch key-in halo lamp,
and cargo lamp. Circuit M1 also powers the glove box
lamp and underhood lamp.
DOOR COURTESY LAMPS
When the BCM receives the courtesy lamp signal,
it broadcasts a message on the CCD bus. The mes-
sage signals the Drivers Door Module (DDM) and
Passenger Door Module (PDM). In response, the
DDM and PDM power the courtesy lamps in the
front doors on circuit M1. Circuit Z1 grounds the
courtesy lamps in the front doors.
Circuit F81 from the circuit breaker in cavity 2 of
the junction block powers the DDM and PDM. Cir-
cuit A250 from fuse 11 in the PDC feeds circuit F81
through the circuit breaker.
8W - 44 - 1
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