
10 INTRODUCTION
•
INTERNATIONAL CONTROL AND DISPLAY SYMBOLS
ID
HIGH
BEAM P
FOG UGHTS -&
HEADLIGHTS,
PARKING UGHTS, PANEL UGHTS TURN SIGNAL A
HAZARD WARNING WINDSHIELD
WASHER
WINDSHIELD WIPER WINDSHIELD WIPER
AND WASHER
AND DEFROSTING *
VENTILATING
FAN 8
M f
REAR
WINDOW DEFOGGER
sp
REARWINLX)W WIPER
CD
l
m
REAR
WINDOW WASHER FUEL ENGINE COOLANT
TEMPERATURE BATTERY CHARGING
CONDITION ENGINE OIL
SEAT
BELT
(©) (®) ky
11 J
LIGHTER
BRAKE
FAILURE
PARKING
BRAKE
FRONT HOOD
REAR
HOOD
(TRUNK)
HORN
11 J
LIGHTER
93IN-9
INTERNATIONAL VEHICLE CONTROL AND DISPLAY
SYMBOLS
The graphic symbols illustrated in the chart below
are used to identify various instrument controls. The
symbols correspond to the controls and displays that are located on the instrument panel.

•
ELECTRICAL
ELECTRICAL
8A - 1
Group
AUDIO
SYSTEMS
8F
BATTERY/STARTER/GENERATOR
SERVICE
.. 8B
BATTERY/STARTING/CHARGING
SYSTEMS
DIAGNOSTICS
8A
HORNS
8G
IGNITION
SYSTEMS
8D
INSTRUMENT PANEL AND
GAUGES
8E
LAMPS
8L
POWER
LOCKS
8P
INDEX
Group
POWER
MIRRORS
8T
POWER
WINDOWS 8S
REAR
WINDOW DEFOGGER 8N
TURN
SIGNALS
AND HAZARD WARNING
FLASHERS
8J
VEHICLE
SPEED
CONTROL SYSTEM 8H WARNING BUZZER SYSTEM 8U
WINDSHIELD WIPERS AND
WASHERS
8K
WIRING DIAGRAMS 8W
BATTERY/STARTING/CHARGING SYSTEMS DIAGNOSTICS
CONTENTS
page
page
BATTERY TEST
PROCEDURES
2 GENERATOR TEST
PROCEDURES
ON VEHICLE . 13
ENGINE
STARTER MOTOR TEST
PROCEDURES
..9 SPECIFICATIONS 18
GENERAL
INFORMATION 1
GENERAL INFORMATION
The Battery, Starting, and Charging Systems oper
ate with one another, and therefore, must be thor
oughly tested as a complete system. In order for the
vehicle to start and charge properly, it must have a
battery that will perform to specifications. The starter
motor, generator, wiring, and electronics also must
perform within specifications. Group 8A covers Start ing (Fig. 1) and Charging (Fig. 2) System diagnostic
procedures. These procedures include the most basic
conventional methods to On-Board Diagnostics (OBD)
built into the Powertrain Control Module (PCM).
Use of an ammeter, volt/ohmmeter, battery
charger, carbon pile rheostat (load tester), and 12
volt test light will be required.
All OBD sensing systems are monitored by the
PCM. The PCM will store in memory any detectable
failure in the monitored circuits. Refer to Using On-
Board Diagnostic System in this group for more in formation.
NEGATIVE
BATTERY
CABLE
A
7
POSITIVE
BATTERY
CABLE
BATTERY
J918A-11
Fig.
1 Starting
System
Components—Typical

•
REAR
WINDOW DEFOGGER
8N - 1
REAR
WINDOW
DEFOGGER
CONTENTS
page
REPAIR
PROCEDURES (GRID LINES,
TERMINALS,
AND
PIGTAILS)
3
GENERAL
INFORMATION
The electrically heated rear window defogger
is
available
on
Ramcharger with sunscreen glass only. The system consists
of a
rear window with
two
ver
tical
bus
bars
and a
series
of
electrically connected
grid lines baked
on the
inside surface. Circuit protection
for the
heated grid circuit
is
pro
vided
by a 18
gauge fusible link wire located
in the
engine compartment.
The
relay circuit
is
protected
by
a 20 amp
fuse, located
in the
fuse block. When
the
rear window defogger switch
is
placed
in
the
ON
position, current
is
directed
to
rear window
grid lines.
The
heated grid lines
in
turn heat
the
rear window
to
clear
the
surface
of fog or
snow.
CAUTION;
Grid lines
can be
damaged
or
scraped
off
with
sharp instruments. Care should
be
taken
in
page
SERVICE
PROCEDURES
4
TEST
PROCEDURES
1
cleaning
the
glass
or
removing foreign materials,
decals
or
stickers. Normal
glass
cleaning solvents
or
hot
water
used
with
rags
or
toweling
is
recom mended.
SYSTEM
DESCRIPTION CONTROL
SWITCH/TIMER
RELAY MODULE
The control switch
and
timer relay
are
integrated
into
a
single panel mounted assembly. Actuating
the
switch energizes
the
electronic timing circuit. This
allows current
to
flow through
the
grid system
for
approximately
10
minutes,
or
until either
the
control
switch
or
ignition
is
turned
off. An
indicating lamp
illuminates
a
lens inlaid
in the
control switch.
TEST PROCEDURES
SYSTEM
TEST
Electrically heated rear window defogger operation
can
be
checked in-vehicle
in the
following manner: (1) Turn
the
ignition
ON.
(2) Turn rear window defogger control switch
ON.
(3) Monitor vehicle voltmeter. With
the
control
switch
ON, a
distinct needle deflection should
be
noted. (4)
The
rear window defogger operation
can be
checked
by
feeling
the
glass.
A
distinct difference
in
temperature between
the
grid lines
and
adjacent clear glass
can be
detected
in 3 to 4
minutes
of
operation. (5) Contact negative lead
of a DC
voltmeter
(Fig.
1),
to
terminal
"B"
(passenger side). Contact positive
lead
to
terminal
"A"
(driver side).
The
voltmeter
should read
10-14
volts. Only steps
(3) and (4) or (5)
above will confirm sys
tem operation. Indicator light illumination means
that there
is
power available
at the
output
of the re
lay only,
and
does
not
verify system operation.
If rear window defogger does
not
operate,
the
prob
lem should
be
isolated
in the
following manner:
(1) Confirm that ignition switch
is ON.
VOLTMETER
Fig.
1
Grid
Line
Test (2) Ensure that heated rear window feed wire
is
connected
to
terminal
or
pigtail
and
that ground wire
is
in
fact grounded.
(3) Ensure that fuse
is
operational
and all
electri
cal connections
are
secure.
When above steps have been completed
and the
system
is
still inoperative,
one or
more
of the
follow
ing
is
defective:
(a) Control switch/timer relay module.

8N
- 2
REAR WINDOW DEFOGGER
• (b) Rear window grid lines (all grid lines would
have to be broken) or one of the feed wires are not
connected for the system to be inoperative.
The following paragraphs outline component check
out procedures.
If turning the switch ON produces severe voltmeter
deflection, the circuit should be closely checked for a shorting condition. If system operation has been verified but indicator
bulb does not light, check and replace bulb.
For detailed wiring information, refer to Group 8W
- Wiring Diagrams.
REAR
WINDOW GRID LINES TEST
Horizontal grid lines and vertical bus bar lines
printed and baked on inside surface of rear window glass (Fig. 1) comprise an electrical parallel circuit.
The electrically conductive lines are made of a silver- ceramic material. When baked onto glass they be
come bonded to the glass and are highly resistant to abrasion. It is possible, however, that a break may
exist or occur in an individual grid line resulting in
no current flow through the line. To detect breaks in
grid lines, the following procedure is required: (1) Turn ignition on and push control switch to
ON. Indicator light should come on. (2) Contact negative lead of a DC voltmeter, to
vertical bus bar connecting grid lines on passenger side of vehicle (point A of Fig. 1). Contact positive
lead of voltmeter, to vertical bus bar on driver side of
vehicle (point B of Fig. 1). Voltmeter should read 10-14 volts. (3) With negative lead of voltmeter, contact a good
body ground point. Voltage reading should not change. A different reading indicates a poor ground connection. (4) Connect negative lead of voltmeter to Point A
on passenger side bus bar and touch each grid line at
Mid-Point with positive lead. A reading of approxi mately 6 volts indicates a line is good. A reading of 0
volts indicates a break in line between Mid-Point C and Point B. A reading of 10-14 volts indicates a
break between Mid-Point C and ground Point A. Move toward break and voltage will change as soon as break is crossed.
CONTROL SWITCH/TIMER MODULE TEST
Control switch/timer relay module may be tested
in-vehicle or bench tested. In vehicle testing is ac
complished in the following manner: (1) Remove switch from instrument panel (refer to
Control Switch Replacement) and leave switch con
nector plugged in. (2) Turn ignition ON.
(3) Using a DC voltmeter, check voltage at termi nals B, I and L (Figs. 2 and 3). Terminals B and I
should confirm a voltage of 10 to 14 volts to ground.
Terminal L should confirm 0 volts to ground. When terminals B and I show no voltage, trace circuit up
stream of switch/relay module for cause:
• wiring cut
• fusible link faulty
• circuit breaker inoperative
• bulkhead connection bad, etc. If terminal L indicates voltage, place switch in
OFF position. If voltage at L is still indicated or in
dicator lamp remains on, switch/relay module should
be replaced.
"XI
FUSE
#14
rr~
P 3
AAAP
P
FUSE
#3
20
AAAP
BATTERY
HEATED
REAR
WINDOW
DEFOGGER
SWITCH
(INSTRUMENT
PANEL)
ON/OFF
ILLUMINATION
LAMP
fez TIMER
L.E.I
INDICATOR
LIGHT
-©-
18
GAUGE
FUSIBLE
LINK
IGNITION POWER
MIDPOINT
"C"
CONNECTOR (TYPICAL)
POINT
"A"
POINT
"B"
GROUND
CONNECTOR
REAR
WINDOW
GRID
LINE
STRUCTURE
Fig.
2
Systems
Electrical Circuit
J928N-5
(4) If the relay checks out to this point, momen
tarily operate switch to ON position. The indicator lamp should come on and remain on for approxi
mately 10 minutes. Terminal L should confirm volt
age.
If the indicator lamp fails to light or voltage at
terminal L is not confirmed the switch/relay module should be replaced.
Bench checking of the relay may be accomplished
in the following manner. By following the in-vehicle
procedure except Step 2: With a DC power supply, apply 12 volts to terminal B and I and ground termi
nal G.

e
,
REAR
WINDOW
DEFOGGER
8N
- 3
L
-
TO
BACK GLASS
B
-
HIGH
AMP
SUPPLY
I
-
IGNITION
G
-
GROUND
S
-
ILLUMINATION
LIGHT
RELAY-TIMER
SWITCH
ASSEMBLY
J908N-8
Fig.
3
Rear Window Defogger
Switch,
Timer,
Relay
Connector
REPAIR
PROCEDURES
(GRID LINES, TERMINALS* AND PIGTAILS)
The
repair
of
grid lines
or the
terminal
is
possible
using
the
MOPAR Repair
Kit
No. 4267922
or
equiv alent.
WARNING: REPAIR
KIT
MAY
CAUSE SKIN
OR
EYE
IRRITATION.
CONTAINS EPOXY RESIN
AND
AMINE TYPE
HARDENER,
HARMFUL
IF
SWALLOWED. AVOID
CONTACT
WITH
SKIN
AND
EYES.
FOR
SKIN,
WASH
AFFECTED AREAS
WITH
SOAP
AND
WATER.
DO
NOT TAKE INTERNALLY.
IF
TAKEN INTERNALLY,
INDUCE VOMITING; CALL
A
PHYSICIAN IMMEDI
ATELY.
IF IN
CONTACT
WITH
EYES,
FLUSH
WITH
PLENTY
OF
WATER.
USE WITH
ADEQUATE VENTI
LATION.
DO
NOT USE
NEAR FIRE
OR
FLAME.
CONTENTS CONTAIN
3%
FLAMMABLE SOLVENTS.
KEEP
OUT
OF
REACH
OF
CHILDREN.
(1) Mask repair area
so
conductive epoxy
can be
extended onto
the
line
or the bus bar
(Fig.
4).
(2) Follow instructions
in
repair
kit for
preparing
damaged area.
(3) Remove package separator clamp
and mix
plas
tic conductive epoxy thoroughly. Fold
in
half and
cut
center corner
to
dispense epoxy.
(4)
For
grid line, mark
off
area
to be
repaired with
masking tape
or a
template (Fig.
4).
(5) Apply epoxy through slit
in
masking tape.
Overlap both ends
of the
break
by at
least
19mm
(0.75
in).
(6)
For a
terminal
or
pigtail replacement, mask
ad
jacent areas
so
epoxy
can be
extended onto line
as
BREAK
GRID
LINE
MASKING TAPE PR1509A
Fig.
4
Grid
Line
Repair
(Typical)
well
as bus bar.
Apply
a
thin layer
of
epoxy
to
area
where terminal
was
fastened
and to
adjacent line.
(7) Apply
a
thin layer
of
conductive epoxy
on
ter
minal
and
place terminal
on
desired location.
To
pre
vent terminal from moving while
the
epoxy
is
curing, it must
be
wedged
or
clamped.
(8) Carefully remove masking tape from grid line.
CAUTION:
Do not
allow
the
glass
surface
to
exceed
400°F,
glass
may
fracture.
(9) Allow epoxy
to
cure
24
hours
at
room tempera
ture
or use
heat
gun
with
a
260°-371°C (500°-700°F) range
for 15
minutes. Hold
gun
approximately 254mm
(10
inches) from repaired area.
(10) After conductive epoxy
is
properly cured
re
move wedge from terminal
and
check
out
operation
of rear window defogger.
Do not
attach connectors
until curing
is
complete.