Jeep Cherokee 2000 Service Manual - page 323
engine, the park/neutral position switch is mounted
on the right side of the automatic transmission case.
The switch is indexed to and driven by the transmis-
sion manual valve shaft. Refer to Park/Neutral
Position Switch in the index of this service manual
for the location of more information on either version
of the park/neutral position switch.
Following are general descriptions of the starter
relay and the starter motor. See the owner’s manual
in the vehicle glove box for more information on the
features, use and operation of the starting system.
Refer to Starting System in the index of this ser-
vice manual for the location of complete wiring dia-
grams for the starting system.
NOTE: This group covers both Left-Hand Drive
(LHD) and Right-Hand Drive (RHD) versions of this
model. Whenever required and feasible, the RHD
versions of affected vehicle components have been
constructed as mirror-image of the LHD versions.
While most of the illustrations used in this group
represent only the LHD version, the diagnostic and
service
procedures
outlined
can
generally
be
applied to either version. Exceptions to this rule
have been clearly identified as LHD or RHD, if a
special illustration or procedure is required.
OPERATION
If the vehicle is equipped with a manual transmis-
sion, the clutch pedal position switch is installed in
series between the ignition switch and the coil bat-
tery terminal of the starter relay. This normally open
switch prevents the starter relay from being ener-
gized when the ignition switch is turned to the
momentary Start position, unless the clutch pedal is
fully depressed. This feature prevents starter motor
operation while the clutch disc and the flywheel are
engaged. The starter relay coil ground terminal is
always grounded on vehicles with a manual trans-
mission.
If the vehicle is equipped with an automatic trans-
mission, battery voltage is supplied through the low-
amperage control circuit to the coil battery terminal
of the starter relay when the ignition switch is
turned to the momentary Start position. The park/
neutral position switch is installed in series between
the starter relay coil ground terminal and ground.
This normally open switch prevents the starter relay
from being energized and the starter motor from
operating unless the automatic transmission gear
selector is in the Neutral or Park positions.
When the starter relay coil windings are energized,
the relay directs battery current to the starter sole-
noid coil windings. When the starter solenoid coil
windings are energized, the solenoid directs battery
current to the starter motor, which cranks the engine
by engaging the starter pinion gear with the starter
ring gear. Once the engine starts, the ignition switch
key is released by the vehicle operator. When the
ignition switch key is released, the switch automati-
cally returns to the On position, which de-energizes
the starting system.
STARTER MOTOR
DESCRIPTION
The starter motors used for both the 2.5L and the
4.0L engines available in this model are not inter-
changeable (Fig. 1). However, each of these starter
motors incorporates several of the same features to
create a reliable, efficient, compact, lightweight and
powerful unit. Both starters feature high torque
direct current electric motors. Inside both starter
motors the commutator of the rotating motor arma-
ture is contacted by four brushes. The starter motor
for the 2.5L engine is driven by four permanent mag-
net field poles, while the starter motor for the 4.0L
engine is driven by four electromagnetic field coils
wound around four pole shoes. The 2.5L starter
motor is rated at 1.2 kilowatts (about 1.6 horse-
power) output at 12 volts, while the 4.0L starter
motor is rated at 1.4 kilowatts (about 1.9 horse-
power) output at 12 volts.
These starter motors are equipped with a plane-
tary gear reduction (intermediate transmission) sys-
tem. The planetary gear reduction system consists of
a gear that is integral to the output end of the elec-
tric motor armature shaft that is in continual
engagement with a larger gear that fits on a spline
on the input end of the starter pinion gear shaft.
This feature makes it possible to reduce the dimen-
sions of the starter. At the same time, it allows
higher
armature
rotational
speed
and
delivers
increased torque through the starter pinion gear.
Fig. 1 Starter Motors
1 – STARTER SOLENOID
8B - 2
STARTING SYSTEMS
XJ
DESCRIPTION AND OPERATION (Continued)