Dodge ram truck 3500 1996 Service Manual page 743

8W - 44 INTERIOR LIGHTING 8W - 44 -1
8W-44 I N T E R I O R L I G H T I N G
INDEX
page
DESCRIPTION AND OPERATION
BUZZER MODULE
2
CARGO LAMPS
2
DAY/NIGHT MIRROR 1
DOME LAMP 1
GLOVE BOX LAMP 1
HELPFUL INFORMATION
2
INTRODUCTION 1
D E S C R I P T I O N A N D O P E R A T I O N
INTRODUCTION
Circuit M l supplies power to the underhood lamp,
glove box lamp, dome lamp, buzzer module, cargo
lamps, vanity lamps and the time delay relay. Circuit
M50 from the time delay relay powers the ignition
switch lamp.
Circuit M l is protected by the Ignition Off Draw
(IOD) fuse i n the fuse block, cavity 17. This fuse is a
15 amp.
Power for the M l fuse is supplied on circuit A7.
This circuit originates i n the Power Distribution Cen­
ter (PDC) and is protected by a 50 amp fuse located
in cavity 1.
KEY-IN-SWITCH HALO LAMP
Circuit M50 from the time delay relay supplies
voltage to the key-in-switch halo lamp. Circuit Z3
provides ground for the lamp.
Circuit M l supplies voltage to the time delay relay.
Circuit M2 provides ground for the relay through the
headlamp switch or the door jamb switch.
TIME DELAY RELAY
The time delay relay is used to allow a time-ON
function for the ignition switch lamp. Power for the
relay is provided on the M l circuit from the IOD fuse
(fuse 17) in the fuse block.
Circuit M2 provides ground for the time delay
relay through the right and left door jamb switches
and the headlamp switch. When a door is OPENED,
or the headlamp switch is moved to the dome/cargo
lamp ON position, a ground path is provided for the
relay on circuit M2. This energizes the relay, causing
the contacts to CLOSE.
When the relay contacts CLOSE, power is provided
through the relay to circuit M50. The M50 circuit
supplies current to the key-in-switch halo lamp. Cir­
cuit Z3 provides ground for the lamp.
page
KEY-IN-SWITCH HALO LAMP . . . . . . . . . . . . . . . . 1
SEAT BELT SWITCH . . .
2
TIME DELAY RELAY 1
UNDERHOOD LAMP 1
VISOR/VANITY LAMPS
2
SCHEMATICS AND DIAGRAMS
WIRING DIAGRAM INDEX . . 2
1L0¥E 101 LAiP
Circuit M l from the IOD fuse (fuse 17) in the fuse
block powers the glove box lamp. A switch, in series
after the lamp, CLOSES when the glove box door is
OPENED. The switch completes a path to ground on
circuit Z3.
UNDERHOOD LAMP
Circuit M l from the IOD fuse (fuse 17) in the fuse
block supplies battery voltage for the underhood
lamp. A mercury switch, in series after the lamp, con­
nects the lamp to ground on circuit Z l . When the
hood is raised, mercury inside the switch moves to a
position where it connects circuit M l to ground cir­
cuit Z l , illuminating the lamp.
DOME LAMP"
Circuit M l from the IOD fuse (fuse 17) in the fuse
block supplies power to the dome lamp. This circuit
is HOT at all times. The ground path for the lamp is
provided in two different ways.
One way is through the door jamb switches. Circuit
M2 connects to the door jamb switches from the
dome lamp. The switches * are connected to ground
circuit Z3. When a door is OPENED, the switch
CLOSES, completing a path to ground on circuit Z3.
The second ground path is through the headlamp
switch. Circuit M2 is spliced in with the headlamp
switch. When the operator turns the headlamp
switch to the dome lamp ON position, a ground path
is provided through the switch on circuit Z3.
DAY/NIGHT MIRROR
The day/night mirror receives power from circuit
L10 when the ignition switch is i n the RUN position.
This circuit is protected by a 10 amp fuse located i n
cavity 15 of the fuse block. Circuit Z4 provides
ground for the day/night mirror.
When the back-up lamps switch CLOSES, circuit
L I provides a signal to the day/night mirror. The day