Electrically Heated Systems - Chrysler 1998 Viper RT/10 Owner's Manual

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ELECTRICALLY HEATED SYSTEMS
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ELECTRICALLY HEATED SYSTEMS
C O N T E N T S
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GENERAL INFORMATION
INTRODUCTION 1
DESCRIPTION AND OPERATION
REAR WINDOW DEFOGGER GRID 1
REAR WINDOW DEFOGGER RELAY 1
REAR WINDOW DEFOGGER SWITCH 1
DIAGNOSIS AND TESTING
REAR WINDOW DEFOGGER GRID 2
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REAR WINDOW DEFOGGER RELAY 2
REAR WINDOW DEFOGGER SWITCH 3
REAR WINDOW DEFOGGER SYSTEM 3
SERVICE PROCEDURES
GRID LINE AND TERMINAL REPAIR 3
REMOVAL AND INSTALLATION
REAR WINDOW DEFOGGER SWITCH 4
G E N E R A L I N F O R M A T I O N
INTRODUCTION
A n electrically heated rear window defogger is
standard factory-installed equipment on the Viper
Coupe. The defogger w i l l only operate when the igni-
t i o n switch is i n the On position. When the defogger
switch is t u r n e d On, an electric heater grid on the
rear window glass is energized. This grid w i l l pro-
duce heat to help clear the window glass of ice, snow,
or fog.
The defogger system is controlled by a switch
located i n the accessory switch bezel, which is near
the bottom of the instrument panel center bezel and
next to the ash receiver. A n amber indicator lamp i n
the switch button w i l l l i g h t to indicate w h e n the
defogger system is t u r n e d on. The instrument cluster
circuitry, which contains the defogger system t i m e r
logic, monitors the state of the defogger switch
through a hard-wired i n p u t . The instrument cluster
circuitry controls the defogger system t h r o u g h a
hard-wired control output to the defogger relay.
The defogger system w i l l be automatically t u r n e d
off after a programmed time i n t e r v a l of about ten
minutes. After the i n i t i a l t i m e i n t e r v a l has expired, i f
the defogger switch is t u r n e d on again d u r i n g the
same ignition cycle, the defogger system w i l l auto-
matically t u r n off after about five minutes.
The defogger system w i l l automatically shut off i f
the ignition switch is t u r n e d to the Off position, or i t
can be t u r n e d off manually by depressing the i n s t r u -
ment panel switch. Refer to the owner's m a n u a l for
more information on the defogger system controls
and operation.
Following are general descriptions of the major
components i n the defogger system. Refer to Group
8W-48 - Rear Window Defogger for complete circuit
descriptions and diagrams.
D E S C R I P T I O N A N D O P E R A T I O N
REAR WINDOW DEFOGGER GRID
The heated rear window glass has two electrically
conductive vertical bus bars and a series of horizon-
tal g r i d lines made of a silver-ceramic material,
w h i c h is baked on and bonded to the inside surface of
the glass. The g r i d lines and bus bars comprise a
parallel electrical circuit.
When the rear window defogger relay is energized,
electrical current is directed to the rear window grid
lines through the bus bars. The g r i d lines heat the
rear window to clear the surface of fog or snow. Pro-
tection for the heated grid circuit is provided by fuse
8 i n the Fuse/Relay Block.
The g r i d lines and bus bars are highly resistant to
abrasion. However, i t is possible for an open circuit
to occur i n an i n d i v i d u a l grid line, resulting i n no
current flow through the line. The g r i d lines can be
damaged or scraped off w i t h sharp instruments. Care
should be taken w h e n cleaning the glass or removing
foreign materials, decals, or stickers from the glass.
N o r m a l glass cleaning solvents or hot water used
w i t h rags or toweling is recommended.
A repair k i t is available to repair the grid lines and
bus bars, or to reinstall the heated glass pigtail
wires.
REAR WINDOW DEFOGGER RELAY
The rear window defogger relay includes the t i m e r
function. Upon i n i t i a l actuation signal from the relay
w i l l stay energized for approximately ten minutes, or
u n t i l the ignition is t u r n e d off or the control switch is
pressed again.
REAR WINDOW DEFOGGER SWITCH
The rear window defogger switch is mounted i n the
instrument panel center bezel next to the power w i n -