1988 JEEP CHEROKEE Ignition Switch positions

assembly. To install, reverse removal procedure.
ADJUSTMENTS
NOTE: The following adjustment procedures should not be necessary
during normal vehicle operation or maintenance. Adjustment
of the listed components should only be required when a
faulty component is replaced with a new one.
IDLE SPEED ACTUATOR (ISA) MOTOR
1) With air cleaner removed, air conditioner off (if
equipped) and engine at normal operating temperature, connect a
tachometer to terminals 1 (+) and 3 (-) of the small diagnostic
connector D1. See Fig. 16. Turn ignition off and observe ISA motor
plunger. The plunger should move to fully extended position.
2) With ISA plunger fully extended, disconnect wire
connector and start engine. Engine speed should be 3300-3700 RPM. If
not, turn hex head screw on end of plunger until correct speed is
obtained.
3) Hold closed throttle switch plunger all the way in while
opening throttle. Release the throttle. Throttle lever should not make
contact with the plunger. If contact is made, inspect throttle
linkage and/or cable for binding or damage. Repair as needed.
4) Reconnect ISA motor wire connector and turn ignition off
for 10 seconds. Motor should move to fully extended position. Start
engine. Engine speed should be 3300-3700 RPM for a short time and
then fall to normal idle. Turn off engine and remove tachometer.
5) When final adjustments have been made, apply thread
sealer to adjustment screw threads to prevent movement. Install air
cleaner.
WIDE OPEN THROTTLE SWITCH
1) Remove the throttle body assembly from the engine, and
loosen 2 WOT switch retaining screws. Hold throttle in wide open
position, and attach a Throttle Angle Gauge (J-26701) to flat surface
of the throttle lever.
2) Rotate scale to align the 15
mark with the pointer.
Level the gauge. Rotate scale to align zero with the pointer, and
close the throttle enough to center bubble. This positions the
throttle at 15
before wide open throttle.
3) Adjust the WOT switch lever on the throttle cam so that
the plunger is just closed at 15
position. Tighten the retaining
screws, and remove the gauge.

throttle body. Connect Exerciser Tool (Part No. 8980 002 646) into
ISS motor. See Fig. 6.
3) Connect Red clip to battery positive cable. Connect
Black clip to battery negative cable. Red light on exerciser tool
will illuminate when properly connected. Start engine.
NOTE: When switch on exerciser tool is in "High" or "Low"
position, light on exerciser tool will flash indicating
voltage pulses are being sent to ISS motor.
4) Move exerciser tool switch to "High" position. Engine
speed should increase. Move switch to "Low" position. Engine speed
should decrease. If engine speed increases or decreases while using
exerciser tool, ISS motor is functioning properly.
5) Disconnect exerciser tool and reconnect ISS motor
connector. If engine speed does not change, turn ignition off and
remove ISS motor from throttle body.
6) With ignition off, switch exerciser tool between "High"
and "Low" positions. Check movement of ISS motor pintle. Pintle
should move in and out. If pintle does not move, replace ISS motor.
7) Start engine and test new ISS motor for proper
operation. If pintle operates properly, check ISS motor bore in
throttle body for blockage and clean as necessary. Reinstall ISS
motor into throttle body.
Fig. 6: ISS Motor Test Connector
Courtesy of Chrysler Motors.
Fuel Injector Test

IG NIT IO N S W IT C H & L O CK C YLIN DER

1988 J e ep C hero ke e
1988 Ignition Switch & Lock Cylinders
JEEP
DESCRIPTION
The ignition switch and lock cylinder is typically mounted on
the steering column and actuated by an ignition key.
SERVICING
To gain access to ignition components on Jeep vehicles, the
steering column must be removed or lowered and the turn signal switch
must be removed.
CAUTION: The lock plate is held by high spring pressure. DO NOT
remove snap ring without using a compressor tool. If the
steering shaft has standard threads, use Compressor Tool
(J-23653); if the shaft has metric threads use Metric
Forcing Screw (J-23653-4).
CAUTION: Special care must be taken to avoid bumping, jolting or
hammering on the steering shaft and gearshift tube.
REMOVAL & INSTALLATION
LOCK CYLINDER
Removal
Turn lock cylinder clockwise 2 detent positions beyond
"OFF-LOCK" position. Compress lock cylinder retaining tab using a thin
bladed screwdriver and remove lock cylinder.
Fig. 1: Typical Column Type Ignition Switch Lock Cylinder Removal
On most vehicles, push in to release lock retainer.
Installation
Insert key in lock. Hold cylinder sleeve, and turn key

If test light glows, check tailgate window motor.
TAILGATE WINDOW MOTOR
Grand Wagoneer
1) Using a 12-volt test light, connect one end of test light
to ground and probe Tan wire at motor. Close safety switch and turn
tailgate window switch to "DOWN" position. If test light glows and
motor does not operate, replace motor. If test light does not glow,
check feed circuit to motor and repair as necessary.
2) Probe Brown wire at motor. Close safety switch and turn
tailgate window switch to "UP" position. If test light glows and motor
does not operate, replace motor. If test light does not glow, check
feed circuit to motor and repair as necessary.
SIDE WINDOW MASTER SWITCH CIRCUIT
1) Remove escutcheon and housing from master switch. Separate
terminal plate by releasing retainer hooks to expose terminal ends.
Turn ignition on.
2) Using a 12-volt test light, connect one lead to Black wire
and other lead to Red terminal. Repeat test at second Black wire. If
test light does not glow in either test, remove lead to Black terminal
and connect to chassis ground.
3) If test light glows, an open exists between master switch
and ground. If test light does not glow, it indicates a defective
circuit breaker or an opening in the Red wire from circuit breaker to
master switch.
SIDE WINDOW CONTROL SWITCH & MOTOR TEST
Grand Wagoneer
1) Connect test light between terminals of Orange and Yellow
wires. Operate control switch up and down. If test light glows in both
switch positions, wires, individual door and master switches are not
defective.
2) Disconnect White and Green motor leads at terminal plate,
and connect to Green and White leads. Operate master switch. If window
goes up and down, motor is okay, but switch is defective. If motor
does not operate, remove trim panel and check connections and leads to
motor. If motor operates, switch is defective.
SIDE WINDOW MOTOR
Connect test battery positive lead to one of the motor
terminals. Connect negative lead to other terminal. Motor should
rotate in one direction to go up or down. Reverse battery leads, motor
should rotate in opposite direction. If window does not move, replace
motor.
SWITCH VOLTAGE TEST
1) Turn ignition on. Remove switch from trim panel.
Disconnect terminal block on wiring harness from switch body. Connect
one lead of test light to Red wire terminal and other end to ground.
2) If test light glows, wiring between battery and switch is
functional. Check continuity in Black wire (ground). If test light
does not glow, check circuit breaker. If okay, check for a broken
wire.
SWITCH UP & SWITCH DOWN TEST

STE ER IN G C O LU M N S W IT C HES

1988 J e ep C hero ke e
1988 STEERING
Jeep Steering Column Switches
All Models
REMOVAL & INSTALLATION
TURN SIGNAL & HAZARD FLASHER SWITCHES
Removal & Installation
1) Place front wheels in straight-ahead position. Disconnect
battery negative cable. Remove the steering wheel. Refer to the
STEERING WHEEL & HORN REMOVAL article.
2) On models with A/T, place selector lever in "PARK"
position. Remove selector lever retaining pin and lever. Using 2
screwdrivers, remove lock plate cover. On models with tilt column,
remove tilt lever.
3) Using Plate Compressor (J-23653-A), compress lock plate.
If shaft has metric threads, use Metric Forcing Screw (J-23653-4)
prior to installing compressor on shaft. Remove and discard lock plate
snap ring. Remove plate compressor
NOTE: The lock plate is under strong spring tension. DO NOT
attempt to remove snap ring without using lock plate
compressor.
4) Remove lock plate, canceling cam, upper bearing preload
spring, spring seat and bearing race (thrust washer on some models).
Depress hazard warning switch while unscrewing from column.
5) On vehicles with A/T, use a paper clip to compress lock
tab retaining shift quadrant light wire in connector block. Disconnect
wire. On all models, remove turn signal lever attaching screw and
lever.
6) On vehicles with cruise control, disconnect 2 of 4 wires
at switch connector. Fold wires back along harness. Tape wires to
harness. Tape a string to harness to aid in removal.
7) Disconnect turn signal switch wire harness at bottom of
steering column. Tape around turn signal switch harness connector to
aid in removal. Remove turn signal switch attaching screws. Remove
switch. To install, reverse removal procedure.
LOCK CYLINDER
Removal
1) Remove horn button and steering wheel. Refer to the
STEERING WHEEL & HORN REMOVAL article. Remove turn signal switch.
Remove key warning buzzer switch and contacts as an assembly, using
needle-nose pliers.
2) On models with standard column, turn ignition lock
cylinder (clockwise) 2 detent positions beyond the "OFF/LOCK"
position. On models with tilt column, turn lock cylinder to "LOCK"
position. On all models, compress lock cylinder retaining tab and
remove lock cylinder from housing. See Fig. 1.

cylinder. Turn cylinder to "OFF-UNLOCK" position. Disconnect switch
from remote rod. Disconnect harness connectors at switch. Remove
switch.
Installation
Move switch slider to "ACC" position. Engage remote rod in
switch slider. Position switch on column, taking care not to move
slider. Hold key in "ACC" position while pushing switch down slightly
to remove slack in actuator rod. Install attaching screws. Connect
harness connectors.
IGNITION SWITCH
Removal (Comanche & Grand Wagoneer)
Remove lower instrument panel trim panel. Insert key in lock
cylinder. Turn cylinder 2 positions beyond the "OFF-UNLOCK" position.
Disconnect switch from remote rod. Disconnect harness connectors at
switch. Remove switch.
Installation
Move switch slider to "ACC" position. Move switch slider back
2 clicks to "OFF-UNLOCK" position. Engage remote rod in switch slider.
Position switch on column. DO NOT move slider while positioning
switch. Install attaching screws. Connect harness connectors.
Fig. 2: Exploded View of Jeep Steering Column Switch Assemblies
Courtesy of Chrysler Motors
TROUBLE SHOOTING
Refer to TROUBLE SHOOTING - BASIC PROCEDURES article in the
GENERAL TROUBLE SHOOTING section.