Electrical JEEP CJ 1953 Owner's Guide

'Jeep*
UNIVERSAL
SERIES
SERVICE
MANUAL

H
Resistance
should be approximately 0.1 ohm.

An
extremely accurate instrument would be neces­
sary
to ascertain shorted turns.
Only
an open condi­
tion can be detected with a commercial ohmmeter.

If
the alternator has been disassembled because of
an
electrical malfunction, replace stator only after

all
components have been checked and found to
be satisfactory.

H-85.
Out-Of-Circuit
Rectifier Diode Test

With
the rectifier diode heat sinks disconnected
from
the stator assembly (Par. H-80), the diodes

can
be individually checked with the Diode Tester

C-3829.
FIG.
H-36—RECTIFIER
DIODE
TEST
POINTS

1— Diode Plate Stud

2—
Diode Terminals

Fig.
H-36 shows the
test
point location for either positive or negative diode.

Plug
Tester C-3829 into a 110-volt AC outlet.
Connect
alligator clip to diode plate stud, and the probe of the tester to each of the three diode ter­

minal's
test
points. Negative diodes
will
give a
negative deflection of the needle and positive
diodes
will
give a positive deflection. The meter

reading
should be the same for each of the diodes

and
should be 2 or over for a
good
diode. If a diode is faulty, replace the entire diode heat sink
assembly. H-86.
Assembling Alternator

Refer
to Fig. H-31.

a.
To install front bearing in front housing, press
the bearing into place on an arbor press using

Bearing
Installer C-3858. Position the split spring

washer
in the front bearing housing oh top of the bearing.

b.
Install
the
rear
bearing on the rotor shaft front
end using Bearing Installer C-3935 as shown in

Fig.
H-37.
FIG.
H-37—INSTALLING
REAR
ROTOR
BEARING

1—
Rear
Bearing Installer C-3935

2—
Rotor
Shaft
C.
Place the rotor assembly
into
position in the
front housing by tapping rotor shaft on a
soft

wood surface.

d.
Position diode assemblies and stator as a unit
into the
rear
housing. Make certain that insulator
washers and insulator
sleeves
are correctly posi­
tioned on the positive diode assembly.

e.
To assemble the subassembly halves of the
alternator
(front
housing and
rear
housing). Slide
the front housing over the stator.
Install
the bolts
and
nuts.
f. Position first the spacer, then the woodruff key
on the rotor shaft and slide on the fan.
Carefully

position the alternator in a vise with the clamps
of the vise held to the pulley. Position the pulley
so it is just starting to slide over the woodruff

key.
Press it into position by tightening nut with

a
wrench. When the pulley is properly positioned,
remove the nut, place the lock washer on the

rotor
shaft, and again replace the nut.

g.
Install
the isolation diode assembly and secure

with
locknuts.

h.
Install
the brush housing in position in the
rear

housing.
Install
the brush housing cover and the
tapping screws.

i.
Turn
the rotor by hand listening carefully to

make
certain there is no interference between the

rotor
and the stator winding.
H-87.
Alternator Installation

To
install the alternator, reverse the procedure 201

H

ELECTRICAL
SYSTEM
FIG.
H-38—WIRE
COLOR CODE
AND

LOCATIONS
FOR
ALTERNATOR HOOK-UP

1— Regulator (Auxiliary)
Terminal
(Cable —
Grey)

2— Output
Terminal:
(Red)

3—
Regulator
Terminal
(Cable —
Grey)

4—
Ground
Terminal
(Cable — Black-White
Tracer)
5—
Field
Terminal
(Cable — Green-White
Tracer)

6—
Ground
(Optional)
Terminal
(Cable — Black-White
Tracer)
REAR
VIEW

35
AMP.
ALTERNATOR
REAR
VIEW
40
& 55 AMP.
ALTERNATOR
given in Par. H-78, adjusting the fan belt to its
proper tension after the alternator is mounted, as described in Par. C-27. Wires should be connected
as shown in Fig. H-38.

When
the vehicle is equipped with a radio, a .55
mfd. capacitor is required on the alternator. Mount
the capacitor strap to a ground terminal and con­
nect the lead to the output terminal.
H-88.
STARTING
SYSTEM
SERVICE
H-89.
Ignition
Switch

The
ignition switch serves both to energize the
ignition system and
engage
the starter switch.
The
ignition switch has four positions: (1) AC­

CESSORY,
(2)
LOCK,
(3) ON, and (4)
START. The
key must be in the switch to turn it to any position other than
LOCK,
and the key can be
removed only in the
LOCK
position.
In "ACC",
a connection is made from the battery

terminal
to the accessory terminal of the switch to
allow accessories such as the radio, blower and/or
windshield wiper to be operated with the ignition, fuel
gauge
and indicator light circuits off.
In "LOCK",
no accessory supplied through the
ignition switch can be operated. Also, the ballast
resistor (V-6
engine
only) circuit to the ignition
coil
(IGN) is grounded.
In
"ON", a connection is made from the battery

terminal
to the accessory terminal so that all
ignition switch supplied accessories can be operated. Also the battery is connected to the ballast resistor
(V-6
engine
only) leading to the ignition coil

(IGN).
From
this same terminal, a lead
into
the
instrument cluster energizes the fuel
gauge
and
indicator lights.
In "START",
all ignition switch supplied acces­
sories are temporarily disconnected. A connection is made to the starter solenoid lead. The charge

and
oil indicator lamps
will
light until the
engine
is started.
H-90.
Ignition
Switch
Removal

a.
Remove the bezel nut and pull back the main
switch body.
Lower
the switch
body
from under the instrument panel so that the wiring harness plug

can
be removed from the prong connection,
b. If the lock cylinder is to be removed, turn the
ignition key to the right and insert a short
piece

of wire or end of a paper clip
into
the lock release

hole
in the switch body. Pressing on the lock
cyl­
inder retainer
will
allow the cylinder to be removed.
H-91.
Ignition
Switch
Installation

Before installing the lock cylinder
into
the main
switch body,
note
the position of the lock cylinder
retainer.

a.
Place the lock cylinder
into
the main switch
body
with the highest part of the lock cylinder
retainer in line with the lock release
hole
in the
main
switch body.
b. Compress the lock cylinder retainer so that the
lock cylinder can be installed all the way
into
the

main
switch
body
or until the retainer can be

seen
through the pin hole.

c.
Install
wiring harness plug
onto
switch
body

prong connection.

d.
Install
this main switch
body
into
the instru­
ment panel opening from the
rear.

e. To make sure that the switch is in its correct position, install the ignition key in the off position.
Then
turn the switch
body
until the key is straight
up and down. Remove the key, install the bezel
nut and secure.
H-92.
PRESTOLITE
STARTING
MOTOR
DAUNTLESS
V-6 and

HURRICANE
F4
ENGINE

The
Prestolite starting motor on the V6
engine
is

similar
in construction (with exception of pinion housings) to the starting motor installed on F4

engines.
The
starter solenoid switch is bolted to the starter
frame.

The
starter is equipped with
sealed-type
absorbent
bronze bearings and no lubricant is required. Service procedures for the Prestolite starter are
given in
Pars.
H-93 to H-107. 202

H

ELECTRICAL
SYSTEM

11035

FIG.
H-40—PRESTOLITE STARTING MOTOR—F4 ENGINE 1— End
Plate

2—
Plug

3—
Thrust
Washer
4—
Brush
Plate Assembly 5— Screw
6—
—Lock
Washer
7—
Insulating
Washer
8—
Terminal

9—
Field
Coil
and Pole
Shoe
Set
10—
Frame

11—
Insulating
Washer

12—
Washer

13— Nut 14—
Lock
Washer

15—
Insulating
Bushing

16—
Pole
Shoe
Screw
17— Sleeve Bearing
18—
Drive
End Frame
19—
Intermediate Bearing

20—
Bendix
Drive

21—
Screw

22—
Lock
Washer

23—
Thrust
Washer

24— Key
25—
Armature

26—
Thru
Bolt

27—
Insulator

brush
and
pull
On
a line parallel with the side of
the
brush.
Take
the
reading
just as the spring leaves the
brush.
It is important that the brush spring
tension be kept within the limits specified at the end of this section. If the tension is too low, there

will
be a loss of efficiency from poor brush contact.
Too
great a tension
will
cause excessive brush and
commutator wear. To change the tension, twist the

spring
at the holder with long-nosed pliers,

c.
Worn
brushes should be replaced. Brushes that
are
soldered to the field coil should be unsoldered

and
the
loop
in the field coil lead should be opened.
Insert
the new brush pigtail to its
full
depth in the
loop. The new brush lead should be tightly clinched

in
the terminal and then soldered to make a strong, low-resistance connection.

H-99.
Commutator

Check
the commutator for wear and discoloration.
If
the commutator is rough or worn the armature should be removed and the commutator turned
down in a lathe. A discolored commutator should
be cleaned with carbon tetrachloride. Never use
emery cloth.

H-100.
Armature

Visually
inspect the armature for mechanical
defects
before checking for shorted or grounded
coils. Use a set of
test
probes for testing armature

circuits.
To
test
the armatures for grounds, touch
one point of the
test
probes to a commutator seg­
ment and touch the other point to the core or shaft. Do not touch the points to the bearing surface or
to the brush surface as the arc formed
will
burn

the smooth finish. If the lamp lights, the coil con­ nected to the commutator segment is grounded.
To
test
for shorted armature coils, a growler as
shown-in Fig. H-42 is necessary. The armature is placed against the core and a steel strip is held
on the armature. The growler is then energized 204

H

ELECTRICAL
SYSTEM

FIG.
H-42—GROWLER
d.
Install
the armature in starter motor frame,
using care to align the four brushes and brush
springs on the commutator so that they are free to
move
and are square on the commutator.

e.
Install
the thrust washer on the shaft.
Lubricate

the plug and bearing in the end plate.
Install
the
end plate.
Install
the two through
bolts
and tighten securely.

f.
On Prestolite V6 starting motors, check pinion position by measuring from the centerline of the
pinion housing mounting bolt
holes
to the outside

edge
of the pinion.
Correct
measurement with the
Bendix
drive retracted is [19,05 mm.] to
%"
[22,23 mm.]; with drive extended, 1%"

[34,93
mm.] to 1^" [38,10]. Adjust by installing

thrust
washers just inside the commutator end
head or intermediate bearing as required. The
Bendix
drive retaining pin must not project
beyond the outside diameter of the pinion
sleeve.

H-104.
Bench Test

The
motor should first be checked to see that the
free running
voltage
and current are within specifi­ cations. To
test,
connect the motor to a battery,
ammeter and voltmeter. If the current is too high
check
the bearing alignment and end play to make

sure
there is no binding or interference. Using a

spring
scale and torque arm check the stall torque to see that the motor is producing its rated
crank­

ing power. The stall torque
will
be product of the

spring
scale reading and the length of the arm

in
feet.
If the torque is not up to specifications

check
the seating of the brushes on the commutator
and
the internal connection of the motor for high
resistance. The Bendix
Folo-Thru-Drive
should be checked for correct operation. The Bendix pinion
should be checked to see that it shifts when the motor is operated under no load.

H-105.
Bendix Folo-Thru Drive (Prestolite)
The
Bendix
Folo-Thru
Drive is designed to over­

come
premature demeshing of the drive pinion
from
the flywheel ring gear until a predetermined

engine
speed is reached. See Fig. H-43. No repairs or adjustments are possible on this

drive
and a
complete
new unit must be installed

if
trouble develops.

H-106.
Lubrication
of
Folo-Thru Drive
A
periodic cleaning and relubrication of the drive is advisable, the frequency of which
will
depend on
the type of service to which the vehicle is sub­
jected and the locale of operation.

a.
Remove the starting motor from the
engine
and take off the outboard housing. The pinion and

barrel
assembly
will
be in the demeshed position
on the screwshaft. Do not
move
it forward
until
after
that portion of the armature shaft ahead
of the pinion has been cleaned. If accidentally ro­
tated to the outer end of the screwshaft it
will

lock
in that position and cannot be forced back.

b.
Do not disassemble the drive for any reason.

c.
Do not dip or wash the drive in any cleaning solution.

d.
Do not remove the drive from the armature
shaft. Remove
excess
oil, grease or foreign matter
from
the armature shaft by wiping it with a clean cloth.
3
10859
FIG.
H-43—BENDIX
FOLO-THRU DRIVE

Dampen
the cloth with kerosene if necessary. A
light film of
SAE
10 oil may then be applied to the shaft.

e.
Now rotate the pinion and
barrel
assembly to the
fully
extended position, thereby exposing the screw­ shaft triple threads. Use a cloth dampened with
kerosene to wipe them clean. Do not use
gaso­
line
or any
commercial cleaner.
If the dirt is

thick
and gummy, apply the kerosene with a small

brush.
Tilt
the starting motor so that a small
amount
will
run under the control nut. Relubricate

with
a thin film of
SAE
10 oil. Use SAE 5 at ex­ tremely low temperatures.

f.
Reassemble the starting motor to the
engine
with the drive in the extended position.
Carefully
mesh the pinion with the flywheel ring gear before
tightening the starter motor mounting bolts. It may 206

H

ELECTRICAL
SYSTEM
sibility
of the cable shorting at the
engine
or frame.
Remove nut and lock washer securing the ignition

wire
to the solenoid
post
and remove the two screws and lock washers securing the solenoid to
the starter frame. Remove the switch,
b.
To install the solenoid switch reverse the re­

moval
procedure given above.

H-10S.
STARTING MOTOR
—
DELCO
DAUNTLESS
V-6
ENGINE

Refer
to Fig. H-45.

The
starting motor used on the Dauntless V-6 en­

gine
has an integral solenoid switch and enclosed
shift lever which first shifts the overrunning clutch
pinion into
engagement
with the ring gear on the
flywheel of the
engine
and then
closes
the electrical
circuit
to cause
engine
cranking. When the
engine

starts,
the overrunning clutch
disengages
to pre­ vent transfer of
engine
speed to the starting motor.

Note:
Should a service replacement starter motor
be required the factory recommends replacement

with
original equipment parts; however, should the need arise an existing starter motor (Delco or
Prestolite) could be replaced with the current
Delco-Remy
starter, model 1108375, with the
following modifications to the wiring harness. If
the existing starter motor wiring harness
does
not
provide a 12 ga. purple conduit wire, (connects the ignition switch to the starter motor) then a 12 ga.

purple
conduit wire 70 inches long, must be in­

stalled.
Should the existing starter motor wiring
harness
contain a 16 ga. light blue conduit wire, (connects the ignition switch and starter motor)
bend this wire back and tape out of the way.

H-109.
Starting Motor Disassembly
a.
Before removing the starting motor from the
engine, disconnect leads and cover battery lead

terminal
with piece of
hose
or tape to prevent
short circuiting.
Note
locations of wiring connec­
tions to assure proper reconnection. Remove the cap screw that secures the starting motor to the
angle bracket on the side of the engine. Remove
the two cap screws that secure the drive end of
the starting motor to the cylinder block; remove
the starting motor.

b.
Remove terminal nut and disconnect field lead,

which
passes through grommet at top of motor,
from
motor terminal of solenoid. Remove two
thru

bolts
from motor. Remove commutator end frame

and
field frame assembly from solenoid and drive assembly.
e.
Pull
out pivot pins of brush holders and remove each of two brush holder and spring assemblies

from
field housing. Remove screws which attach
brushes and leads to holders.

d.
Remove armature and drive assembly from
drive
housing. Remove thrust collar from pinion
end of armature shaft. Remove leather thrust

washer
from
opposite
end of shaft.
e. To separate drive assembly from
armature,
place

a
metal cylinder of proper size (J^" [12,7 mm.]
pipe coupling is satisfactory) over end of armature
shaft to bear against the pinion
stop
retainer. Tap
retainer
toward armature to
expose
snap ring as
shown in
Fig.
H-47. Remove snap ring from
groove
in
shaft; slide retainer and pinion drive assembly

from
shaft. Remove assist spring from shaft,

f.
Remove two screws holding solenoid switch to
drive
housing remove switch. Remove small nut

and
insulating washer from the solenoid S terminal.
Remove nut and insulating washer from the
sole­

noid battery (large) terminal. Remove two screws that attach switch cover to solenoid and remove cover for inspection of switch parts. Remove shift
lever fulcrum bolt and remove shift lever, plunger,

and
return spring.
12765
FIG.
H-47—REMOVING PINION
DRIVE
ASSEMBLY

FROM
ARMATURE SHAFT

1— XA ' Pipe Coupling

2—
Snap
Ring
and Retainer

3—
Armature
Shaft
4—
Drive
Assembly
H-110.
Starting
Motor
Cleaning and
Inspection

a.
Wipe all parts clean with clean cloths. The
arma­
ture,
field coils, and drive assembly must not be
cleaned by any degreasing or high temperature
method.
This
might damage insulation so that a
short
circuit
or ground would subsequently develop.
It
would also remove lubricant originally packed

in
the overrunning clutch so that clutch would

soon
be ruined.

b.
Carefully
inspect all parts visually for wear or
damage. Make necessary repairs or replace unserv­
iceable parts. Any soldering must be
done
with

rosin
flux.

Note:
Never use acid flux when solding any elec­

trical
connections and never use emery cloth to
clean
armature
commutator or other
electrical
units. 208

H

ELECTRICAL
SYSTEM
FIG.
H-49—INSTALLING PINION
STOP RETAINER AND THRUST

COLLAR
ON ARMATURE SHAFT
1—
Retainer

2—
Snap
Ring

3—
Thrust
Collar

4—
Drive
Assembly 5—
Retainer

6—
Groove
in Armature Shaft 7—
Snap
Ring

e. Place thrust collar on armature shaft with shoulder next to snap
ring.
Move the retainer
into contact with
ring.
Using pliers on
opposite

sides of shaft,
squeeze
retainer and thrust collar

together
until snap ring is forced into the retainer.
See Fig. H-49, right hand view.

f.
Lubricate
bearing of drive housing with silicone grease and install armature and drive assembly
in
housing.
g. If field coils were removed from field frame, position coils of replacement field coil assembly
on
pole
shoes
and mount each
pole
shoe
in field
frame
with a
pole
shoe
screw. Use care in tighten­ ing screws to avoid distortion of parts. Be certain
that screws are securely tightened. Insert ends of
field
coil
leads through rubber bushing in field
frame.

h.
Position field frame assembly over armature as­
sembly so that its dowel pin
engages
the
hole
in

drive
housing. Use care to prevent damage to brushes and brush holders. Make sure that brushes

are
properly sealed on commutator.

i.
Install
leather thrust washer on commutator end
of armature assembly.
Lubricate
bearing in com­
mutator end frame with silicone grease and position
end frame to field frame so that armature shaft
enters bearing. Secure field frame and end frame
to drive housing with two
thru
bolts. Connect field leads to motor terminal of solenoid with connect­ing nut.

j.
Whenever the starting motor is disassembled
and
reassembled, the pinion clearance should be
checked.
This
is to make sure that proper clear­
ance exists
between
the pinion and the pinion

stop
retainer when pinion is in cranking position.

Lack
of clearance would prevent solenoid starter

switch
from closing properly; too much clearance
would cause improper pinion
engagement
in ring gear.

k.
Supply 6 volts (3 battery cells or a
6-volt
bat­

tery)
between
S terminal of the solenoid and ground (starter frame).
Caution:
Do not supply more than 6 volts or the
motor
will
operate. As a further precaution to
prevent motor operation, connect a heavy jumper

wire
from the solenoid motor terminal to ground.

I.
After energizing the solenoid, push the drive as­
sembly away from the
stop
retainer as far as pos­
sible and use a feeler
gauge
to check clearance

between
pinion and retainer. See Fig. H-50. If pinion clearance is not .010" to .140" [0,25 a 3,55

mm.],
there is either excessive wear or improper as­
sembly of solenoid linkage or shift lever mechanism.
12771
FIG.
H-50—MEASURING PINION CLEARANCE
1—
Press
Rearward

2—
Pinion

3—
Retainer

4— .010* to .140* Clearance 5—
Feeler
Gauge
210

'Jeep'
UNIVERSAL
SERIES SERVICE
MANUAL

H
Note:
Pinion clearance cannot be adjusted. If
clearance is not correct, motor must be disassem­
bled and checked for the above mentioned defects.

Any
defective parts must be replaced.
H-118. Starting Motor Test —
Genera!

To
obtain
full
performance data on a starting motor, or to determine the cause of abnormal
operation, the motor should be submitted to no-
load and locked armature
tests,
with equipment designed for such
tests.
A high-current variable resistance is required to obtain the specified volt­
age at the starting motor.
This
is necessary since
a
small variation in the
voltage
will
produce a
marked
difference in the current
drawn.

H-119.
Starting Motor No-Load Test

This
test
requires a DC voltmeter capable of
read­

ing
voltages
in a 12-volt
circuit,
a DC ammeter

with
maximum range of several hundred amperes,
a
high-current variable resistance, an rpm. in­

dicator,
and a fully-charged, 12-volt battery.

a.
Connect a jumper lead
between
S terminal
and
large battery terminal of starter solenoid.
Con­
nect voltmeter
between
either of
these
terminals (positive) and motor frame (negative, ground).

Connect
ammeter and variable resistance in series

between
positive terminal of battery and battery

terminal
of solenoid. Set up rpm. indicator to show starting motor speed.
b.
Initially,
adjust variable resistance to a value of
approximately .25 ohm. To complete the
circuit,

connect negative terminal of battery to motor

frame.
Adjust variable resistance to obtain a volt­ meter reading of 10.6 volts;
note
speed of starting motor and ammeter reading. Motor speed should
be
6750
to
10,500
rpm.; ammeter reading should
be 50 to 80 amperes.
c. Rated speed and current indicate normal condi­
tion of the starting motor. Low speed and high
cur­
rent
may show friction; this could be caused by
tight, dirty, or worn bearings, bent armature shaft,

or
a
loose
field
pole
shoe
dragging against the

armature.
It could also be caused by a short-cir­ cuited armature, or by grounded armature or field
coils.

d.
Failure
to operate and high current indicates

a
direct short circuit to ground at either the battery

terminal
or field coils.
e.
Failure
to operate and no current are usually
caused by broken brush springs, worn brushes, high insulation
between
commutator
bars,
or
some
other
condition preventing
good
contact
between
the brushes and commutator. It can also be caused by
open circuit in either the field coils or armature coils.
f. Low speed and low current show high resistance due to poor connections, defective leads, dirty com­
mutator, or one of the conditions mentioned in e,
above.
g. High speed and high current indicates a short
circuit
in the field coils. H-120-
Locked
Armature Test

This
test
requires a DC voltmeter with range ap­

propriate
to read
voltages
in a 12-volt
circuit,
a DC
ammeter with maximum range of several hundred
amperes, a high-current variable resistance, a
clamping fixture to lock
together
the motor shaft

and
case, and a fully-charged 12-volt battery.

a.
Connect a jumper lead
between
S terminal and
large battery terminal of starter solenoid. Connect
voltmeter
between
either of
these
terminals (posi­
tive) and motor frame (negative, ground). Connect
ammeter and variable resistance in series
between
positive terminal of battery and battery terminal
of solenoid.
Install
clamping fixture to lock motor
shaft and case
together
securely.
b.
Initially,
adjust variable resistance to approxi­
mately .05 ohm. To complete the
circuit,
connect
negative terminal of battery to motor frame. Ad­

just
variable resistance to obtain a voltmeter
read­
ing of 4.0 volts. Ammeter reading should be 280
to 320 amperes.

H-121.
Solenoid Starter Switch — Delco

The
solenoid-type switch is mounted directly on
the starting motor.
This
type of switch is energized
by turning the ignition key to the extreme right position. Should the solenoid switch
fail
in service

it
is necessary to install a new assembly.

Should
a starting motor
fail
to deliver maximum power the fault may be due to
voltage
drop at the

starter
switch contacts due to corrosion or burning.

Check
the switch by comparing the
voltage
at the
battery across the terminals. The
voltage
drop
should not exceed .05 volts per 100 amperes.
In
order to remove the starter solenoid, it is neces­

sary
to remove the starter assembly.

H-122.
ELECTRICAL
INSTRUMENTS

H-123.
Fuel
Gauge —
CJ-3B

The
fuel
gauge
circuit is composed of the indicating

unit,
mounted on the instrument panel, and the
fuel tank unit, connected by a single wire through the ignition switch.

Should
the
gauge
fail
to register, check all wire con­ nections to be sure they are tight and clean; also
be sure both units are well grounded. If, after this
check, the
gauge
does
not indicate properly, remove
the wire from the tank unit and connect it to a
new tank unit which must be grounded to the tank

or
frame for
test.
Turn
the ignition switch "ON"
and
move
the float arm through its range of travel,
watching the dash unit to determine if it indicates
correctly.
If it fails to do so the trouble is probably

in
the dash unit and it should be replaced.

Should
a new tank unit be unavailable for this
test,
disconnect tank unit wire at the instrument panel

gauge.
Connect one lead of a 12 V, 1 CP
test
light
to the instrument panel unit terminal and with the
ignition switch
"ON"
ground the other lead. If the
unit is operating correctly the pointer
will
move

approximately three-quarter across the
dial.
Do not attempt to repair either unit; replacement
is the only precedure. 211

H

ELECTRICAL
SYSTEM
H-124. Testing Indicators and Gauges

Two
gauges
(fuel and temperature) and two in­ dicators (oil pressure and battery charge) that are
located in the instrument cluster are electrically operated.

The
fuel
gauge
is connected by a single wire to a
float-and-slide-rheostat sending unit in the fuel
tank.

The
temperature
gauge
is connected by a single

wire
to a resistance-type sending unit mounted on the engine.

The
battery charge indicator operates when there
is a difference in potential
between
the generator
and
the battery
.The
battery charge indicator lights
when the generator is not charging the battery. The
indicator
light
goes
out when the generator
begins

to charge the battery.

The
oil pressure indicator is connected by a single

wire
to a diaphragm switch located on the engine.
When
engine
oil pressure is low or zero and the
ignition switch is on, the oil pressure indicator
will

light. When
engine
speed is increased slightly above idle speed, raising the oil pressure to approximately 6 psi. [0,2 kg-cm2], the diaphragm switch
will
open the circuit and the indicator light
will
go out.

A
voltage
regulator maintains a constant
voltage
to the
gauges
in normal operation. On early vehicles,
this
voltage
regulator was mounted on the
rear
of
the instrument cluster. On current vehicles, the
voltage
regulator is integral with the fuel
gauge.

Should
trouble
develop
in the
gauges,
first check the regulator (fuel
gauge
on current production vehicle). If the
voltage
to the regulator is below 10 volts system low
gauge
readings
will
result.
Voltage in
excess
of 16 volts
will
not affect
gauge

readings but may result in premature wear of the
regulator contacts. If the
voltage
to the regulator is

within
the above limits, check the electrical con­ nections to the regulator (or fuel gauge), especially
the ground connection. If the readings of all the
gauges
is too high, or they all read too low, replace
the regulator (or fuel gauge).

If
the temperature
gauge
or heat indicator in the
instrument cluster have failed, the cause may
originate from the jumper bar shorting out against the instrument case.
Check
the jumper bar
between

the temperature
gauge
and heat indicator at the

rear
of the instrument case. On later production vehicles, the jumper bar is covered with an in­
sulating
sleeve
to protect it from shorting out
against the instrument case. If the jumper bar

does
not have this
sleeve,
either install one or

wrap
the bar with plastic electrical tape to
half

an
inch [12,7 mm.] from each end. When installing the jumper bar, be sure the curved
segment
is
closest to the fuel
gauge.

Should
only one of the two
gauges
register incor­
rectly,
check the lead wire from the
gauge
to the
sending unit for shorts or open connections. Next disconnect the
gauge
from the sending unit, and
connect the
gauge
to a new fuel tank sending unit

which
has been grounded to the vehicle.
If
the
gauge
registers incorrectly when operating the new unit,
replace the
gauge;
if correctly, replace the sending

unit.

Should
a new fuel tank unit not be available for testing, use a 12-volt
test
light in its place. When
the
gauge
is operating correctly, the pointer
will

move
approximately three-quarters across the
dial.

On
some
vehicles, the temperature
gauge
may
register on or
close
to the H (hot)
mark
when
coolant temperature is
190°F.
to
200°F.
[88°C.
a

93°C.].
In such cases, a 25-ohm,
1-watt
resistor
may be installed on the temperature
gauge
which

will
place the pointer just beyond the center
mark
at a coolant temperature of
190°F.
to
200°F.
Install

the resistor
between
the two terminals on the back
of the
gauge.
Insulate the
exposed
leads of the resistor with electrical tape.

If
the oil pressure indicator
does
not indicate cor­

rectly,
first check the light bulb. Next check all
connections and lead wires. If, after all possible

defects
are corrected, the indicator light
does
not go on and off properly, then the diaphragm type
switch in the cylinder block should be replaced.

H-12S.
LIGHTING SYSTEM The
wiring of the lighting systems is shown in
the wiring diagrams, which indicate the various units in relation to their positions in the vehicle.
The
wires in the various circuits are of different
colors or are marked by tracers to aid when check­
ing individual circuits.

The
lighting circuits of all models are protected by

an
overload circuit breaker mounted on the back of the main light switch and no replaceable fuse is
required.

The
upper and lower headlight beams are con­
trolled by a
foot
switch located on the toe board
to the left of the clutch pedal.
H-126.
Main
Light
Switch

This
switch is a dual functioning unit having two

push-pull
positions and a rotary action. When
pulled out to the first position, the front parking
and
tail
lights are turned on. When pulled all the
way out to the second position, the headlights and
tail
lights are turned on. Rotating the switch to
the right dims the instrument cluster lighting.

The
switch may be removed from the instrument
panel by first loosening the set screw in the control
knob and removing the knob. The retaining nut may then be removed and the switch removed
through the
rear
of the instrument panel.
FIG.
H-51—MAIN
LIGHT
SWITCH
(EARLY)

1—
Battery
4—Parking Lights
2—
Rear
Lights 5—Auxiliary

3—
Head
Lights
212

H

ELECTRICAL
SYSTEM

14379

FIG.
H-56—PARKING
AND SIGNAL LIGHT (LATE) 1—
Screw

2—
Lens
3—
Gasket

4—
Bulb
5—
Cable

6— Housing H-131. Head
Lamp
Aiming Preparation

All
Jeep Universal-series lamps must be aimed on
the low beam. Lamps may be aimed either with mechanical aimers or by using a screen. If me­

chanical
aimers C-3674 are used,
follow
instruction
supplied with the aiming equipment. If a screen is to be used, preparation for aiming is as follows:

a.
Locate the vehicle in a darkened area with a level floor area and with a screen (may be a wall) having a nonreflecting white surface. A reference
line should be marked on the floor 25
feet
[7,62 m.]
away from and parallel to the screen. Position the vehicle perpendicular to the screen and with the
front head lamps directly over the reference line.
b. Locate the middle
tape
on the screen so that
it is aligned with the center line of the vehicle.
c. Equalize all tire pressures.

d.
Rock the vehicle from side to side to equalize springs and shock absorbers.
e. Measure the distance
between
vehicle head lamp centers.
Then,
position marker
tapes
vertically on
the screen to the right and
left
of the middle
tape
at half this distance.

f.
Measure the distance from the center of each
lamp to the surface on which the vehicle rests.
Position a marker
tape
horizontally on the screen

FIG.
H-57—TAIL, STOP AND

DIRECTIONAL
LIGHT
1—
Screw

2—
Lens

3—
Gasket

4—
Bulb
5— Housing and Cable Assembly
6— Nut and Lockwasher 10441
FIG.
H-58—TAIL AND
STOP LIGHT (EARLY)

1
—Ring

2—
Lens
3—
Gasket

4—
Retainer
5—
Bulb
6—
Gasket

7— Housing and Socket 214

ELECTRICAL
SYSTEM

14385

FIG.
H-61—BACK-UP
LIGHT
1—
Snap
Ring
2—
Lens

3—
Gasket

4—
Bulb
5—
Housing
and
Cable
On
late production
T14A
transmissions the backup
light switch is threaded into the right
rear
corner
of the cover housing and is activated by the move­
ment of the reverse shift
rail.

The
backup light switch is not serviceable and
must be replaced if defective.

Bulbs
can be replaced by removing the snap
ring,

lens and gasket from the assembly.

H-136.
License Plate
Light

On
CJ-5A,
CJ-6A
and current production vehicles
the license plate light is attached to the tailgate
and
is of the swing-type design to enable the
license plate to be visible when the tailgate is in
the down psoition. The bulb can be changed by
removing
the clear plastic lens. On early production
vehicles the license plate light is integral with the

tail
light assembly.

H-137.
Horn
The
horn is mounted under the hood on the
left

front
fender. The horn is sounded by pressing the
button located at the top center of the steering
wheel.

To
remove the horn wire, disconnect the wire at
the snap connection at the base of the steering
column.
Pull
off the rubber horn button cap and
the brass contact cap from the steering wheel nut.

This
will
expose
the contact tip of the horn wire.

Pull
the wire out of the steering column from the top. Refer to Fig. H-62.

H-13S.
Directional
Signals

Fig.
H-63 shows the
wiring
of a
composite
direction­

al
signal
circuit.
The most frequent causes of
failure
in
the directional signal system are
loose
connec­
tions and burned-out bulbs. A flashing rate

approximately
twice the normal rate usually in­
dicates a burned-out bulb in the
circuit.
11087

FIG.
H-62—HORN
BUTTON 1—
Cap
2— Nut
3—
Horn
Button
Spring
Cup 4—
Ferrule

5—
Horn
Cable

6—
Contact
Disc

7—
Steering
Wheel
8—
Cup
9—
Bearing
Spring
Seat
10—
Steering
Column

11—
Tube

12—
Bearing

13—
Bearing
Spring

14—
Horn
Button
Spring

15—
Retainer
Spring
When
trouble in the signal switch is suspected it
is advisable to make the following
test
to definitely
locate the trouble before
going
to the effort of

removing
the signal switch. If, for example, the
right
rear
stop
light and right front parking light

are
inoperative and switch failure is indicated, first put the control lever in neutral position.
Then

disconnect the wire to the right side
circuit
and
touch it to or bridge it to the
"L"
terminal, thus
by-passing the signal switch. If the right side cir- 10609

FIG.
H-63—DIRECTIONAL SIGNAL
CIRCUIT

1—
Flasher

2—
Ignition
Switch

3—
Control
4—
Light
Switch
5— Stop
Light
Switch
216