1994 JEEP CHEROKEE Service Repair Manual

(9) Hold driver's side switch in LOCK position.
Measure voltage at lock relay terminal 3 (30). Meter
should read battery voltage. If OK, next step. If not,
replace lock relay.
(10) Hold driver's side switch in UNLOCK posi-
tion. Measure voltage at unlock relay terminal 3
(30). Meter should read battery voltage. If OK, check
connections and door motor. If not, replace unlock re-
lay.
(11) Repeat procedures for passenger's side switch.
Fig. 1 Door Lock/Unlock Relays
DRIVERS DOOR POWER LOCK SWITCHÐ2-DOOR LEFT HAND DRIVE
8P - 2 POWER DOOR LOCKSJ

DRIVERS DOOR POWER LOCK SWITCHÐ2-DOOR RIGHT HAND DRIVE
JPOWER DOOR LOCKS 8P - 3

DRIVERS DOOR POWER LOCK SWITCHÐ4-DOOR
8P - 4 POWER DOOR LOCKSJ

PASSENGER DOOR LOCK SWITCH
JPOWER DOOR LOCKS 8P - 5

ACTUATOR MOTOR STALL TEST
To test the actuator motor, connect an ammeter in
series with the motor and operate the door switch.
Replace the actuator motor if current draw exceeds 8
amps at room temperature or if the actuator does not
complete its travel in less than one second. Refer to
Solenoid and Latch Assembly Replacement procedures.
SWITCH REPLACEMENT
(1) Remove the interior door latch release assem-
bly and control panel retaining screws (Fig. 2).
(2) Disconnect the control linkage and the wire
harness connector.
(3) Remove the latch release and control panel as-
sembly.
(4) The switch is retained to the panel with clips
(Fig. 3). Push in on the retainer part of the clip and
pry the clips.
(5) To install switch, position switch and press in
retainer clips until they snap into position.
SOLENOID AND LATCH ASSEMBLY REPLACEMENT
(1) Remove interior door latch release assembly
and control panel retaining screws (Fig. 2).
(2) Disconnect control linkage and wire harness
connector.
(3) Remove latch release and control panel assem-
bly.
(4) Remove armrest lower retaining screws.
(5) Swing armrest downward to a vertical position.
This is necessary to disconnect armrest from upper
retainer clip (Fig. 4).
(6) Pull armrest straight out from trim panel.
(7) Remove trim panel with a wide flat blade tool
(Fig. 5).
To aid in removal of trim panel, start at bot-
tom of panel.
(8) Remove plastic water dam sheet.
(9) Remove latch retaining screws (Fig. 6).(10) Grind out or drill out the lock solenoid rivets
and remove solenoid with latch assembly and remote
control rods (Fig. 7).
(11) Place lock solenoid, latch and remote control
rods in door.
(12) Attach lock solenoid to door panel with pop
rivets or nuts and screws.
(13) Attach latch. Tighten screws to 9 Nzm(7ft.
lbs.) torque.
(14) Install door trim panel and plastic water dam
sheet.
Fig. 3 Power Lock Switch Removal
Fig. 2 Power Window/Lock Control Panel Removal/
Installation
Fig. 4 Armrest Retainer Clip
8P - 6 POWER DOOR LOCKSJ

(15) Using an adhesive/sealant, install plastic wa-
ter dam sheet.
(16) Place trim panel in installation position and
press in the nylon retainers.
(17) Install armrest.
(18) Install latch release assembly and control
panel.
LIFTGATE LOCK CYLINDER REPLACEMENT
(1) Remove 2 screws at the top outside edges of the
liftgate trim panel.
(2) Remove trim panel with a wide flat blade tool
(Fig. 8).
To aid in removal of trim panel, start at bot-
tom of panel.
(3) Disconnect lock actuator linkage clip (Fig. 9).
(4) Remove 3 latch retaining screws (Fig. 10).
Fig. 5 Trim Panel Removal
Fig. 6 Latch Removal/Installation
Fig. 7 Solenoid Removal/Installation
Fig. 8 Liftgate Trim Panel Removal
Fig. 9 Lock Actuator Linkage Clip
JPOWER DOOR LOCKS 8P - 7

(5) Remove latch.
(6) Drill out 2 rivets and remove solenoid.
(7) To install solenoid, reverse the removal proce-
dures.
(8) Tighten latch screws to 9 Nzm (7 ft. lbs.) torque.
KEYLESS ENTRY
INDEX
page page
Diagnosing Power Door Locks............... 9
Door Lock/Unlock Relay Replacement......... 12
Receiver................................ 8
Receiver Service......................... 11
System Description........................ 8System Operation......................... 9
Transmitter.............................. 8
Transmitter Programming................... 9
Transmitter Service........................ 9
SYSTEM DESCRIPTION
The keyless entry system consists of a portable re-
mote control transmitter and a receiver mounted in
the overhead console or between the sun visors. Sys-
tem operation is based on a coded infrared signal
from the transmitter to the receiver. The transmitter
is programmed into the receiver providing the correct
programming sequence is met.
When the keyless entry system is activated, the cor-
responding relay operates to supply voltage to the mo-
tors. The use of either relay determines the polarity of
the voltage that is supplied to the door lock motors.
When the keyless entry system is used, the trans-
mitter sends a signal to the keyless entry module. If
the doors are unlocked, the module activates a tran-
sistor switch to apply voltage to the lock relay coil.
The coil is energized to close the normally open con-
tacts of the lock relay. Battery voltage from the relay
is applied to the door lock motors to lock the doors.
Current flows in the same path to ground as it does
when the master door lock switch is used.When the doors are locked, the keyless entry mod-
ule applies voltage to the unlock relay coil and a
similar action takes places to unlock the doors.
TRANSMITTER
The pocket size, solid state transmitter operates on
(2) 3-volt lithium (CR1616) batteries (Fig. 1). The
transmitter is activated by pressing either the LOCK
or UNLOCK button. This closes the internal contacts
that complete the battery circuit.
The battery voltage activates the transmitter diode
which in turn generates a coded infrared signal. The
signal is transmitted as pulses of infrared light.
If the red LED on the side of the transmitter does
not light when the transmitter is activated, the bat-
teries are low.
RECEIVER
The receiver is in circuit with the electric door lock
system. The coded infrared signal is picked up by the
receiver diode and is shaped, amplified and decoded by
an integrated circuit within the receiver. If the signal
Fig. 10 Latch Assembly Removal/Installation
8P - 8 POWER DOOR LOCKSJ

code received matches the code in the receiver memory
circuit, the receiver triggers the door lock/unlock relays.
The relays complete the circuit to the electric door lock
solenoid to either lock or unlock the doors.
SYSTEM OPERATION
To activate the system, aim the transmitter diode
toward the receiver and press the transmitter signal
button to lock or unlock the doors as desired.
Effective transmitter range is 4.75 meters (15 ft.)
with the transmitter positioned no more than 45 de-
grees from the receiver centerline.
For complete circuit diagrams refer to Group
8W - Wiring Diagrams.
TRANSMITTER PROGRAMMING
Up to 4 Transmitter Identification Codes (TIC's) can
be programed into the receiver at any given time.
(1) Open the driver's door of the vehicle. Leave it
open through the programming procedure.
(2) Move the mechanical door lock lever to the
LOCK position.
(3) Turn the ignition switch to the ON position.
(4) Within 20 seconds, aim a transmitter at the re-
ceiver dome and press the LOCK button for at least
5 seconds. Once the receiver accepts the program-
ming code, the driver's door will unlock.
(5) Once the first transmitter has been pro-
grammed, additional transmitters (up to 4) may be
programmed into the receiver. Within 20 seconds of
the previous transmitter programming, move the me-
chanical door lock lever to the LOCK position. Aimanother transmitter at the receiver dome and press
the LOCK button for at least 5 seconds. The door
lock will cycle again.
(6) To lock the programmed codes into the re-
ceiver, the ignition switch must be turned OFF and
back ON within 20 seconds after programming the
last transmitter's code. At that time, all previous
codes are erased from the module.
DIAGNOSING POWER DOOR LOCKS
NO DOOR LOCKS OPERATE, USING
TRANSMITTER
(1) Measure resistance at keyless entry module
terminal 10. Meter should read zero ohms. If not, re-
pair open to ground.
(2) Measure voltage at keyless entry module termi-
nal 1. Meter should read battery voltage.Battery
voltage must be at least 9 volts for this system to
operate.If not, repair open to #9 fuse.
(3) Jumper test leads keyless entry module termi-
nal 1 to terminal 3. Doors should lock. If OK, replace
module. If not, repair open from terminal 3 to lock
relay terminal 1.
(4) Jumper test leads keyless entry module termi-
nal 1 to terminal 4. Door should unlock. If OK, re-
place module. If not, repair open from terminal 4 to
unlock relay terminal 1.
TRANSMITTER SERVICE
If the receiver malfunctions, only the receiver will
have to be replaced. The new receiver will have to be
reprogrammed. If a transmitter is lost, replace the
transmitter and reprogram the receiver.
Batteries may not be supplied with some re-
placement transmitters. Be sure to check a re-
placement transmitter before attempting to
activate the system.
TRANSMITTER BATTERY REPLACEMENT
(1) Separate transmitter at middle seam (Fig. 2).
Fig. 2 Separate Transmitter Halves
Fig. 1 Keyless Entry Transmitter
JPOWER DOOR LOCKS 8P - 9