1994 JEEP CHEROKEE battery

²Battery side of fuse No.12 should be battery volt-
age. If not, repair open from ignition switch.
²A/C blower switch (terminal A) should be battery
voltage. If not, repair open from fuse No.12.
2. BLOWER SWITCHÐIgnition in RUN.
²A/C blower switch (Terminal A) with blower
switch in any position should be battery voltage. If
not, repair open from fuse panel.
²A/C blower switch (Terminal L) with blower
switch in LO should be battery voltage. If not, re-
place switch.
²A/C blower switch (Terminal M) with blower
switch in MED should be battery voltage. If not, re-
place switch.
²A/C blower switch (Terminal H) with blower
switch in HI should be battery voltage. If not, replace
switch.
3. BLOWER MOTOR
Turn ignition switch to RUN for voltage tests and
turn ignition switch to OFF for resistance tests.
²A/C blower housing to ground (Terminal G) should
be 0 ohms. If not, repair ground connection. If the
blower motor is still inoperative, replace motor.
²A/C blower motor connector (Terminal C) with
blower switch in LO should be battery voltage. If not,
repair open from blower switch. If the blower motor
is still inoperative, replace motor.
²A/C blower motor connector (Terminal B) with
blower switch in MED should be battery voltage. If
not, repair open from blower switch. If the blower
motor is still inoperative, replace motor.
²A/C blower motor connector (Terminal A) with
blower switch in HI should be battery voltage. If not,
repair open from blower switch. If the blower motor
is still inoperative, replace motor.COMPRESSOR CLUTCH
Refer to Group 8W, Wiring Diagrams for complete
system schematic.
With engine running, Engine Controller may delay
A/C clutch up to 30 seconds.
1. COMPRESSOR CLUTCH.
²Jumper wire from battery positive post to A/C
compressor clutch connector (Terminal A), clutch
should engage. If not, go to next step with jumper in-
stalled.
²Jumper wire from clutch coil frame to chassis
ground, clutch should engage. If not, repair clutch
coil ground or replace coil.
2. LOW PRESSURE SWITCH
Turn ignition switch to RUN, A/C blower switch to
ON and thermostatic control set to MAX cool.
²A/C low pressure switch connector (Terminal A)
should be battery voltage. If not, proceed to thermo-
static control tests (Step 3).
²Jumper wire across A/C low pressure switch con-
nector (Terminals A and B), clutch should engage. If
not, check system refrigerant charge. If system is
properly charged, replace A/C low pressure switch.
3. THERMOSTATIC CONTROL
Turn ignition switch to RUN, A/C blower switch to
ON and thermostatic control set to MAX cool.
²Thermostatic control connector (Terminal A)
should be battery voltage. If not, repair open from
blower switch.
²Thermostatic control connector (Terminal B)
should be battery voltage. If not, replace thermo-
static control.
²A/C low pressure switch connector (Terminal A)
should be battery voltage. If not, repair open from
thermostatic control.
24 - 16 HEATING AND AIR CONDITIONINGJ

COMPRESSOR OVERHAUL
INDEX
page page
Compressor............................. 17
Compressor Isolation...................... 17
Description............................. 17Magnetic Clutch......................... 18
Purging Compressor of Air................. 17
DESCRIPTION
The A/C system uses a Sanden compressor. This
compressor is a 7 piston design. Designated the SD-
709, the compressor is mounted on the front right
side of the engine and is driven by a serpentine belt.
System lubrication is provided by 135cc615cc (4.6
cu. in.60.5 cu. in.) of 500 viscosity refrigerant oil.
The clutch used on the compressor consists of 3 ba-
sic components: the pulley, front plate and the field
coil. The pulley and field coil are attached to the
front head of the compressor with tapered snap rings.
The hub is keyed to the compressor shaft and is re-
tained on the shaft with a self-locking nut. Special
service tools are required to remove and install the
clutch plate on the compressor shaft.
COMPRESSOR ISOLATION
It is not necessary to discharge the system for com-
pressor removal. The compressor can be isolated from
the remainder of the system and eliminate the need
for recharging when performing compressor service.
(1) Connect pressure gauge and manifold.
(2) Close both gauge hand valves.
(3) Mid-position both service valves.
WARNING: USE EXTREME CAUTION WHEN THE
ENGINE IS OPERATING. DO NOT STAND IN A DI-
RECT LINE WITH THE FAN. DO NOT PUT YOUR
HANDS NEAR THE PULLEYS, BELTS OR FAN. DO
NOT WEAR LOOSE CLOTHING.
(4) Start the engine and operate the air condition-
ing system.
(5) Turn the suction service valve slowly clockwise
toward the front seated position.
(6) When pressure drops to zero, stop the engine
and compressor and quickly finish front-seating the
suction service valve.
(7) Front-seat the discharge service valve.
(8) Loosen the oil level check plug slowly to re-
lease any internal pressure in the compressor.
The compressor is now isolated from the remainder
of the system.
The service valves can be removed from the com-
pressor.
PURGING COMPRESSOR OF AIR
The compressor must be purged of air whenever it
has been isolated for an oil level check or other ser-
vice procedures without discharging the entire sys-
tem.
(1) Cap the service gauge ports on both of the ser-
vice valves.
(2) Back-seat the suction service valve to allow the
system refrigerant to enter the compressor.
(3) Place the discharge service valve in the mid-po-
sition or cracked-position.
(4) Loosen the discharge service valve gauge port
cap to permit the refrigerant to force any air out of
the compressor.
(5) Back-seat the discharge service valve and
tighten the gauge port cap.
(6) The compressor is now ready for service.
COMPRESSOR
REMOVAL
(1) Isolate the compressor.
(2) Disconnect negative cable from battery.
(3) Disconnect the clutch lead wire.
(4) Remove the discharge and inlet (suction) ser-
vice valves from the compressor. Plug or tape all the
openings.
(5) Remove the serpentine drive belt (refer to
Group 7, Cooling System for the proper procedure).
(6) Remove the bolts and lift the compressor from
the mounting bracket (Figs. 1 and 2).
INSTALLATION
If a replacement compressor is being installed;
check the oil level. Add or subtract oil as neces-
sary and install the magnetic clutch on the com-
pressor.
(1) If the mounting bracket was removed, install
the bracket to the block. Tighten the mounting bolts
to 27 NIm (20 ft. lbs.) torque.
(2) Install the compressor on the mounting
bracket. Tighten the bolts to 27 NIm (20 ft. lbs.)
torque.
(3) Install the serpentine drive belt (refer to Group
7, Cooling System for the proper procedure).
(4) Tighten the serpentine drive belt to the speci-
fied tension.
²New belt tensionÐ800-900 N (180-200 lb-f).
JHEATING AND AIR CONDITIONING 24 - 17

²Used belt tensionÐ623-712 N (140-160 lb-f).
(5) Remove the tape or plastic plugs from all the
suction and discharge openings and install the ser-
vice valves on the compressor.
(6) Connect the clutch lead wire.
(7) Connect negative cable to battery.
(8) Evacuate, charge and test the system for leaks.
MAGNETIC CLUTCH
The magnetic clutch consists of a stationary elec-
tro-magnetic coil and a rotating pulley and plate as-
sembly.
The electromagnetic coil is retained on the com-
pressor with a snap ring and is dimpled to maintain
its position.The pulley and plate assembly are mounted on the
compressor shaft.
When the compressor is not in operation, the pul-
ley free wheels on the clutch hub bearing. When the
coil is energized the plate is magnetically engaged
with the pulley and turns the compressor shaft.
REMOVAL
(1) Insert the 2 pins of the front plate spanner into
any 2 threaded holes of the clutch front plate (Fig.
3). Hold clutch plate stationary. Remove hex nut
with 19 mm (3/4 inch) socket (Fig. 3).
(2) Remove clutch front plate using puller. Align
puller center bolt to compressor shaft (Fig. 4). Thumb
tighten the puller bolts into the threaded holes.
(3) Turn center bolt clockwise with 19 mm (3/4
inch) socket until front plate is loosened.
Fig. 1 Compressor and Mounting Bracket (LH Drive
Vehicles)
Fig. 2 Compressor and Mounting Bracket (RH Drive
Vehicles)
Fig. 3 Hex Nut Removal
Fig. 4 Clutch Front Plate Removal
24 - 18 HEATING AND AIR CONDITIONINGJ

HEATER AND A/C CONTROL PANEL REPLACEMENT
(1) Disconnect negative cable from battery.
(2) Remove the instrument panel bezel attaching
screws and remove the instrument panel bezel (Fig.
1). Bezel is snap fit at locations shown.
(3) Remove the radio attaching screws (Fig. 2).
(4) Disconnect the radio electrical connector,
ground lead and antenna lead (Fig. 3).
(5) Remove the A/C-heater control panel screws
(Fig. 4).(6) Remove the electrical connectors (Fig. 5).
(7) Disconnect the vacuum hoses by releasing the
locking tabs (Fig. 6).
(8) Remove the control cable locking tab by using
a screwdriver to release the tab (Fig. 7).
(9) Remove the ring on the end of the control cable
from the arm on the bottom of the control panel (Fig.
8).
To Install the A/C-heater control panel, reverse the
removal procedures.
BLOWER MOTOR/FAN REPLACEMENT
The blower motor and fan are accessible and
may be removed from the engine compartment.
2.5L ENGINE
(1) Disconnect the blower motor wires (Fig. 9).
(2) Remove the blower motor and fan assembly
mounting screws (Fig. 10).
(3) Remove the blower motor and fan assembly.
(4) Remove the blower motor fan from the motor
shaft for access to the motor attaching nuts (Fig. 11).
Fig. 1 Instrument Bezel
Fig. 2 Radio Mounting Screws
Fig. 3 Radio Wiring Harness
Fig. 4 Control Panel Mounting Screws
24 - 26 HEATING AND AIR CONDITIONINGJ

(4) Connect the heater hoses to the heater core.
(5) Fill the cooling system.
HEATER CORE HOUSING REPLACEMENT
(1) Remove the evaporator/blower housing.
(2) Remove the heater core.
(3) Remove the defroster duct.
(4) Disconnect the vacuum hoses from the heater
core housing vacuum motors.
(5) Remove the heater housing retaining nuts in
the engine compartment. Remove the heater core
housing.
(6) Transfer the vacuum motors, etc. to the re-
placement housing.
To install the heater core housing, reverse the re-
moval procedure.
DEFROSTER DUCT REPLACEMENT
REMOVAL
(1) Disconnect negative cable from battery.
(2) If equipped with center console remove the con-
sole as follows:
(a) MANUAL TRANSMISSIONÐRemove shift
knob, boot and bezel.
(b) AUTOMATIC TRANSMISSIONÐRemove
shift handle by pulling up. Remove the shift bezel.
(c) POWER MIRRORSÐPry mirror switch out of
console cover (Fig. 13). Disconnect switch connector
(Fig. 14).
(d) Remove console cover screws (Fig. 14).
(e) Remove console cover from base (Fig. 15).
(f) Remove console base (Fig. 15).
(3) Remove the lower instrument panel.
(4) Remove the left kick panel.
(5) Remove the instrument panel retaining bolt.
(6) Remove the instrument panel retaining bolts
located at the steering column.
(7) Remove the right and left A-pillar trim.(8) Remove the defroster bezel attaching screws
and bezel (Fig. 16).
Fig. 13 Power Mirror Switch
Fig. 14 Console Cover Screws and Power Mirror
Switch Connector
Fig. 15 Console Cover and Base
JHEATING AND AIR CONDITIONING 24 - 29

(9) Remove the instrument panel retaining screws.
(10) Lower the steering column.
(11) Pull the instrument panel, approximately 3
inches, away from the dash panel.
(12) Remove the defroster duct retaining screws.
Remove the defroster duct.
(13) Disconnect the hoses.
INSTALLATION
(1) Connect the hoses.
(2) Install the defroster duct. Install the defroster
duct retaining screws.
(3) Position the instrument panel into the dash
panel.
(4) Position the steering column.
(5) Install the instrument panel retaining screws.
(6) Install the defroster bezel attaching screws and
bezel.
(7) Install the right and left A-pillar trim.
(8) Install the instrument panel retaining bolts lo-
cated at the steering column. Tighten the steering
column retaining nuts to 27 NIm (20 ft. lbs.) torque.
(9) Install and tighten the instrument panel re-
taining bolt.
(10) Install the left kick panel.
(11) Install the lower instrument panel.
(12) If equipped with center console, install the
console as follows:
(a) Install console base.
(b) Install console cover to base.
(c) Install and tighten console cover screws.
(d) POWER MIRRORSÐSnap mirror switch into
the console cover. Connect switch connector.
(e) MANUAL TRANSMISSIONÐInstall shift
knob, boot and bezel.(f) AUTOMATIC TRANSMISSIONÐInstall the
shift bezel. Install shift handle by pushing down.
(13) Connect negative cable to battery.
HEATER CONTROL CABLE REPLACEMENT
(1) Remove the heater control panel.
(2) Remove the clip and the cable self-adjusting
clip from the blend air door lever at the bottom of
the evaporator/blower housing (Fig. 17). Then re-
move the cable by squeezing the tabs with needle
nose pliers being careful not to break the housing.
To install the heater control cable, reverse the re-
moval procedure.
HEATER/DEFROSTER/INSTRUMENT PANEL OUTLET
DOOR VACUUM MOTOR REPLACEMENT
(1) If equipped with center console remove the con-
sole as follows:
(a) MANUAL TRANSMISSIONÐRemove shift
knob, boot and bezel.
(b) AUTOMATIC TRANSMISSIONÐRemove
shift handle by pulling up. Remove the shift bezel.
(c) POWER MIRRORSÐPry mirror switch out of
console cover (Fig. 13). Disconnect switch connector
(Fig. 14).
(d) Remove console cover screws (Fig. 14).
(e) Remove console cover from base (Fig. 15).
(f) Remove console base.
(2) Remove the lower instrument panel.
(3) Disconnect the vacuum hose(s) from the vac-
uum motor.
(4) Remove the vacuum motor attaching nuts and
remove the vacuum motor from the bracket.
Fig. 16 Defroster Bezel
Fig. 17 Heater Control
24 - 30 HEATING AND AIR CONDITIONINGJ

EVAPORATOR/BLOWER HOUSING
REMOVAL
(1) Disconnect negative cable from battery.
(2) Discharge the A/C system as described in this
section and disconnect the A/C hoses from the expan-
sion valve.
(3) Disconnect the blower motor wires and the vent
tube.
(4) If equipped with center console remove the con-
sole as follows:
(a) MANUAL TRANSMISSIONÐRemove shift
knob, boot and bezel.
(b) AUTOMATIC TRANSMISSIONÐRemove
shift handle by pulling up. Remove the shift bezel.
(c) POWER MIRRORSÐPry mirror switch out of
console cover (Fig. 13) and disconnect switch con-
nector (Fig. 14).
(d) Remove console cover screws (Fig. 14).
(e) Remove console cover from base (Fig. 15).
(f) Remove console base.
(5) Remove the lower instrument panel.
(6) Disconnect the electrical connections at the
blower motor resistors and the A/C thermostat. Dis-
connect the vacuum hose at the vacuum motor (Fig.
23).
(7) Cut the plastic retaining strap that retains the
evaporator/blower housing to the heater core housing
(Fig. 24).
(8) Disconnect and remove the heater control ca-
ble.
(9) Remove the clip at the rear of the blower hous-
ing flange and remove the retaining screws.(10) Remove the housing attaching nuts from the
studs on the engine compartment side of the dash
panel (Fig. 25). Remove the evaporator drain tube.
(11) Remove the right kick panel and then remove
the instrument panel support bolt.
(12) To disengage the housing studs from the dash
panel, gently pull out on the right side of the dash.
Then rotate the housing downward and toward the
rear of the vehicle. Remove the evaporator/blower
housing.
Fig. 23 Evaporator Housing Components
Fig. 24 Evaporator Housing
Fig. 25 Evaporator Housing Mounting
JHEATING AND AIR CONDITIONING 24 - 33

INSTALLATION
(1) Position the evaporator/blower housing into
place, being sure to line up the housings using the
provided alignment tabs (Figs. 26 and 27).
(2) Install the housing retaining screws and the
rear housing clip (Fig. 25).
CAUTION: When installing the evaporator/blower
housing, DO NOT trap wires between the housing
fresh air inlet and the dash panel (right side of
housing).
(3) Install the housing retaining nuts on the en-
gine compartment side of the dash panel (Fig. 25).(4) Connect the A/C hoses to the expansion valve
and connect the heater blower motor wires.
(5) Attach the wire connections at the blower mo-
tor resistors and the A/C thermostat (Fig. 23).
(6) Connect the vacuum hose at the vacuum motor
and attach the heater control cable.
(7) Install the instrument panel bolt and the kick
panel.
(8) Install the lower instrument panel and screws.
(9) Install the console (if equipped).
(10) Connect negative cable to battery.
(11) Evacuate and charge the A/C system as out-
lined in this section.
(12) Start the vehicle and check for proper opera-
tion at all vacuum motors.
EVAPORATOR COIL
REMOVAL
(1) Remove the evaporator/blower housing.
(2) Remove the top housing retaining screws. Re-
move the top of the evaporator housing (Fig. 28).
(3) Remove the thermostatic switch and capillary
tube after removing the top of the evaporator hous-
ing.
(4) Remove the evaporator retaining screws and
lift the evaporator out of the housing (Fig. 29).
(5) Remove the expansion valve from the evapora-
tor.
INSTALLATION
(1) Install the expansion valve into the evaporator.
(2) Position the evaporator in the housing. Install
and tighten the evaporator retaining screws (Fig.
29).
(3) Install the thermostatic switch and capillary
tube. Install the top of the evaporator housing.
(4) Position the top of the evaporator housing in
place. Install and tighten the top housing retaining
screws.
Fig. 26 Evaporator Housing Alignment Tab
Fig. 27 Evaporator Housing
Fig. 28 Top of Housing
24 - 34 HEATING AND AIR CONDITIONINGJ