2002 JEEP GRAND CHEROKEE connector

REAR ABSORBER
REMOVAL
(1) Remove rear fascia, refer to (Refer to 13 -
FRAMES & BUMPERS/BUMPERS/REAR FASCIA -
REMOVAL).
(2) Remove rivets attaching absorber to rear cross-
member (Fig. 5).
(3) Separate absorber from vehicle.
INSTALLATION
(1) Position absorber on vehicle.
(2) Install rivets attaching absorber to rear cross-
member (Fig. 2).
(3) Install rear fascia, refer to (Refer to 13 -
FRAMES & BUMPERS/BUMPERS/REAR FASCIA -
INSTALLATION).
REAR FASCIA
REMOVAL
(1) Raise and support vehicle.
(2) Remove wheels.
(3) Remove plastic push pins attaching fascia to
fuel tank skid plate.
(4) Remove plastic rivets attaching fascia to wheel
liner.
Fig. 1 Front Fascia
1 - BODY
2 - FASCIA
Fig. 2 Front Fascia
1 - WHEEL LINER
2 - FASCIA
3 - FOG LAMP CONNECTOR
4 - PLASTIC PUSH PIN
5 - PLASTIC RIVET
Fig. 3 Front Fascia
1 - SCREW
2 - FASCIA
13 - 2 FRAME & BUMPERSWJ
FRONT FASCIA (Continued)

TRAILER HITCH
REMOVAL
(1) Remove rear fascia, refer to (Refer to 13 -
FRAMES & BUMPERS/BUMPERS/REAR FASCIA -
REMOVAL).
(2) Remove screws attaching trailer harness plug
to trailer hitch.
(3) Disconnect harness connector from harness
plug.
(4) Position support stands under trailer hitch.
(5) Remove bolts attaching trailer hitch to frame
rails (Fig. 13).
(6) Separate trailer hitch from vehicle.
INSTALLATION
(1) Position trailer hitch on support stands.
(2) Position trailer hitch on vehicle.
(3) Install bolts attaching trailer hitch to frame
rails. Tighten bolts to 68 N´m (50 lbs.) torque.(4) Connect harness connector to harness plug.
(5) Position harness plug in trailer hitch and
install screws.
(6) Install rear fascia, refer to (Refer to 13 -
FRAMES & BUMPERS/BUMPERS/REAR FASCIA -
INSTALLATION).
TRANSFER CASE SKID PLATE
REMOVAL
(1) Support skid plate.
(2) Remove bolts that attach skid plate to trans-
mission support crossmember and frame sill (Fig.
14).
(3) Remove support and skid plate from vehicle.
INSTALLATION
(1) Install nutserts, if removed.
(2) Position and support skid plate at the frame
sill and transmission support crossmember.
(3) Attach skid plate to frame sill and crossmem-
ber with the bolts. Tighten bolts to 34 N´m (25 ft. lbs)
torque.
Fig. 13 Trailer Hitch
1 - FUEL TANK
2 - TRAILER HITCH
Fig. 14 Transfer Case Skid Plate
1 - TRANSFER CASE
2 - NUTSERT
3 - SKID PLATE
4 - CROSSMEMBER
13 - 8 FRAME & BUMPERSWJ

STANDARD PROCEDURE - FUEL SYSTEM
PRESSURE RELEASE
Use following procedure if the fuel injector
rail is, or is not equipped with a fuel pressure
test port.
(1) Remove fuel fill cap.
(2) Remove fuel pump relay from Power Distribu-
tion Center (PDC). For location of relay, refer to label
on underside of PDC cover.
(3) Start and run engine until it stalls.
(4) Attempt restarting engine until it will no
longer run.
(5) Turn ignition key to OFF position.
CAUTION: Steps 1, 2, 3 and 4 must be performed to
relieve high pressure fuel from within fuel rail. Do
not attempt to use following steps to relieve this
pressure as excessive fuel will be forced into a cyl-
inder chamber.
(6) Unplug connector from any fuel injector.
(7) Attach one end of a jumper wire with alligator
clips (18 gauge or smaller) to either injector terminal.(8) Connect other end of jumper wire to positive
side of battery.
(9) Connect one end of a second jumper wire to
remaining injector terminal.
CAUTION: Powering an injector for more than a few
seconds will permanently damage the injector.
(10) Momentarily touch other end of jumper wire
to negative terminal of battery for no more than a
few seconds.
(11) Place a rag or towel below fuel line quick-con-
nect fitting at fuel rail.
(12) Disconnect quick-connect fitting at fuel rail.
Refer to Quick-Connect Fittings.
(13) Return fuel pump relay to PDC.
(14) One or more Diagnostic Trouble Codes (DTC's)
may have been stored in PCM memory due to fuel
pump relay removal. The DRBtscan tool must be
used to erase a DTC.
SPECIFICATIONS
FUEL SYSTEM PRESSURE
339 kPa   34 kPa (49.2 psi   5 psi).
TORQUE - FUEL DELIVERY
DESCRIPTION N-m Ft. Lbs. In. Lbs.
Accelerator Pedal Bracket Mounting Nuts
(without adjustable pedals)12  2 - 105  20
Fuel Filter/Fuel Press. Reg. Bolts 3 - 26
Fuel Hose Clamps 3 - 26
Fuel Injector Rail Mounting Bolts -4.0L Engine 11 - 100
Fuel Injector Rail Mounting Bolts -4.7L V-8
Engine11 - 100
Fuel Pump Module Locknut 74 55 -
Fuel Tank Filler Tube-to-Body Mounting Bolts 2 - 15
Fuel Tank-to-Body Mounting Bolts 88 65 -
Fuel Tank Support Bracket Bolts (large brackets) 88 65 -
Fuel Tank Support Bracket Bolts (small bracket) 5 - 45
Fuel Tank Support Bracket Nuts (large brackets) 61 45 -
Fuel Tank Heat Shield Nuts (shield-to-tank) 9 - 85
Fuel Tank Heat Shield Nuts (shield-to-body) 3 - 25
14 - 4 FUEL DELIVERYWJ
FUEL DELIVERY (Continued)

(3) Apply a small amount of clean engine oil to
o-rings.
(4) Position filter/regulator to body and install 2
bolts. Tighten bolts to 3 N´m (30 in. lbs.) torque.
(5) Connect 3 fittings. Refer to Quick-Connect Fit-
tings.
(6) Connect negative battery cable to battery.
(7) Start engine and check for leaks.
FUEL LEVEL SENDING UNIT /
SENSOR
DESCRIPTION
The fuel gauge sending unit (fuel level sensor) is
attached to the side of the fuel pump module. The
sending unit consists of a float, an arm, and a vari-
able resistor track (card).
OPERATION
The fuel pump module has 4 different circuits
(wires). Two of these circuits are used for the fuel
gauge sending unit for fuel gauge operation, and for
certain OBD II emission requirements. The other 2
wires are used for electric fuel pump operation.
For Fuel Gauge Operation:A constant input
voltage source of about 12 volts (battery voltage) is
supplied to the resistor track on the fuel gauge send-
ing unit. This is fed directly from the Powertrain
Control Module (PCM).NOTE: For diagnostic pur-
poses, this 12V power source can only be veri-fied with the circuit opened (fuel pump module
electrical connector unplugged). With the con-
nectors plugged, output voltages will vary from
about 0.6 volts at FULL, to about 8.6 volts at
EMPTY (about 8.6 volts at EMPTY for Jeep
models, and about 7.0 volts at EMPTY for
Dodge Truck models).The resistor track is used to
vary the voltage (resistance) depending on fuel tank
float level. As fuel level increases, the float and arm
move up, which decreases voltage. As fuel level
decreases, the float and arm move down, which
increases voltage. The varied voltage signal is
returned back to the PCM through the sensor return
circuit.
Both of the electrical circuits between the fuel
gauge sending unit and the PCM are hard-wired (not
multi-plexed). After the voltage signal is sent from
the resistor track, and back to the PCM, the PCM
will interpret the resistance (voltage) data and send
a message across the multi-plex bus circuits to the
instrument panel cluster. Here it is translated into
the appropriate fuel gauge level reading. Refer to
Instrument Panel for additional information.
For OBD II Emission Monitor Requirements:
The PCM will monitor the voltage output sent from
the resistor track on the sending unit to indicate fuel
level. The purpose of this feature is to prevent the
OBD II system from recording/setting false misfire
and fuel system monitor diagnostic trouble codes.
The feature is activated if the fuel level in the tank
is less than approximately 15 percent of its rated
capacity. If equipped with a Leak Detection Pump
(EVAP system monitor), this feature will also be acti-
vated if the fuel level in the tank is more than
approximately 85 percent of its rated capacity.
DIAGNOSIS AND TESTING - FUEL LEVEL
SENDING UNIT
The fuel level sending unit contains a variable
resistor (track). As the float moves up or down, elec-
trical resistance will change. Refer to Instrument
Panel and Gauges for Fuel Gauge testing. To test the
gauge sending unit only, it must be removed from
vehicle. The unit is part of the fuel pump module.
Refer to Fuel Pump Module Removal/Installation for
procedures. Measure the resistance across the send-
ing unit terminals. With float in up position, resis-
tance should be 20 ohms (+/- 5%). With float in down
position, resistance should be 270 ohms (+/- 5%).
REMOVAL
The fuel gauge sending unit (fuel level sensor) and
float assembly is located on the side of fuel pump
module (Fig. 6). The fuel pump module is located
within the fuel tank.
Fig. 5 Fuel Filter/Fuel Pressure Regulator Removal/
Installation
1 - FUEL FILTER/FUEL PRESSURE REGULATOR
2 - MOUNTING BOLTS (2)
WJFUEL DELIVERY 14 - 7
FUEL FILTER/PRESSURE REGULATOR (Continued)

(1) Remove fuel tank. Refer to Fuel Tank Removal/
Installation.(2) Remove fuel pump module. Refer to Fuel Pump
Module Removal/Installation.
(3) Remove electrical wire connector at sending
unit terminals.
(4) Press upward on release tab (Fig. 7) to remove
sending unit from pump module.
INSTALLATION
The fuel gauge sending unit (fuel level sensor) and
float assembly is located on the side of fuel pump
module (Fig. 6). The fuel pump module is located
within the fuel tank.
(1) Position sending unit to pump module and
snap into place.
(2) Connect electrical connector to terminals.
(3) Install fuel pump module. Refer to Fuel Pump
Module Removal/Installation.
(4) Install fuel tank. Refer to Fuel Tank Removal/
Installation.
FUEL LINES
DESCRIPTION
Also refer to Quick-Connect Fittings.
WARNING: THE FUEL SYSTEM IS UNDER A CON-
STANT PRESSURE (EVEN WITH THE ENGINE OFF).
BEFORE SERVICING ANY FUEL SYSTEM HOSES,
FITTINGS OR LINES, THE FUEL SYSTEM PRES-
SURE MUST BE RELEASED. REFER TO THE FUEL
SYSTEM PRESSURE RELEASE PROCEDURE IN
THIS GROUP.
The lines/tubes/hoses used on fuel injected vehicles
are of a special construction. This is due to the
higher fuel pressures and the possibility of contami-
nated fuel in this system. If it is necessary to replace
these lines/tubes/hoses, only those marked EFM/EFI
may be used.
If equipped:The hose clamps used to secure rub-
ber hoses on fuel injected vehicles are of a special
rolled edge construction. This construction is used to
prevent the edge of the clamp from cutting into the
hose. Only these rolled edge type clamps may be
used in this system. All other types of clamps may
cut into the hoses and cause high-pressure fuel leaks.
Use new original equipment type hose clamps.
FUEL PUMP
DESCRIPTION
The electric fuel pump is located inside of the fuel
pump module. A 12 volt, permanent magnet, electric
motor powers the fuel pump. The electric fuel pump
is not a separate, serviceable component.
Fig. 6 Fuel Gauge Sending Unit Location
1 - FUEL PUMP MODULE
2 - FUEL GAUGE FLOAT
3 - ELECTRIC FUEL PUMP
4 - INLET FILTER
5 - FUEL GAUGE SENDING UNIT
6 - PIGTAIL HARNESS
Fig. 7 Fuel Gauge Sending Unit Release Tab
1 - ELECTRICAL CONNECTOR
2 - FUEL GAUGE SENDING UNIT
3 - RELEASE TAB
4 - FUEL PUMP MODULE
14 - 8 FUEL DELIVERYWJ
FUEL LEVEL SENDING UNIT / SENSOR (Continued)

OPERATION
Voltage to operate the electric pump is supplied
through the fuel pump relay.
Fuel is drawn in through a filter at the bottom of
the module and pushed through the electric motor
gearset to the pump outlet.
Check Valve Operation:The pump outlet con-
tains a one-way check valve to prevent fuel flow back
into the tank and to maintain fuel supply line pres-
sure (engine warm) when pump is not operational. It
is also used to keep the fuel supply line full of gaso-
line when pump is not operational. After the vehicle
has cooled down, fuel pressure may drop to 0 psi
(cold fluid contracts), but liquid gasoline will remain
in fuel supply line between the check valve and fuel
injectors.Fuel pressure that has dropped to 0
psi on a cooled down vehicle (engine off) is a
normal condition.Refer to the Fuel Pressure Leak
Down Test for more information.
The electric fuel pump is not a separate, service-
able component.
DIAGNOSIS AND TESTING
DIAGNOSIS AND TESTING - FUEL PUMP
CAPACITY TEST
Before performing this test, verify fuel pump
pressure. Refer to Fuel Pump Pressure Test.
Use this test in conjunction with the Fuel Pres-
sure Leak Down Test.
(1) Release fuel system pressure. Refer to Fuel
Pressure Release Procedure.
(2) Disconnect fuel supply line at fuel rail. Refer to
Quick-Connect Fittings. Some engines may require
air cleaner housing removal before line disconnection.
(3) Obtain correct Fuel Line Pressure Test Adapter
Tool Hose. Tool number 6539 is used for 5/16º fuel
lines and tool number 6631 is used for 3/8º fuel lines.
(4) Connect correct Fuel Line Pressure Test
Adapter Tool Hose into disconnected fuel supply line.
Insert other end of Adaptor Tool Hose into a gradu-
ated container.
(5) Remove fuel fill cap.
(6) To activate fuel pump and pressurize system,
obtain DRBtscan tool and actuate ASD Fuel System
Test.
(7) A good fuel pump will deliver at least 1/4 liter
of fuel in 7 seconds. Do not operate fuel pump for
longer than 7 seconds with fuel line disconnected as
fuel pump module reservoir may run empty.
(a) If capacity is lower than specification, but
fuel pump can be heard operating through fuel fill
cap opening, check for a kinked/damaged fuel sup-
ply line somewhere between fuel rail and fuel
pump module.(b) If line is not kinked/damaged, and fuel pres-
sure is OK, but capacity is low, replace fuel filter/
fuel pressure regulator. The filter/regulator may be
serviced separately on certain applications. Refer
to Fuel Filter/Fuel Pressure Regulator Removal/In-
stallation for additional information.
(c) If both fuel pressure and capacity are low,
replace fuel pump module assembly. Refer to Fuel
Pump Module Removal/Installation.
DIAGNOSIS AND TESTING - FUEL PUMP
AMPERAGE TEST
This amperage (current draw) test is to be done in
conjunction with the Fuel Pump Pressure Test, Fuel
Pump Capacity Test and Fuel Pressure Leak Down
Test. Before performing the amperage test, be sure
the temperature of the fuel tank is above 50É F (10É
C).
The DRBtScan Tool along with the DRB Low Cur-
rent Shunt (LCS) adapter (Fig. 8) and its test leads
will be used to check fuel pump amperage specifica-
tions.
(1) Be sure fuel tank contains fuel before starting
test. If tank is empty or near empty, amperage read-
ings will be incorrect.
(2) Obtain LCS adapter.
(3) Plug cable from LCS adapter into DRB scan
tool at SET 1 receptacle.
(4) Plug DRB into vehicle 16±way connector (data
link connector).
Fig. 8 LOW CURRENT SHUNT
1 - LOW CURRENT SHUNT ADAPTER
2 - PLUG TO DRB
3 - TEST LEAD RECEPTACLES
WJFUEL DELIVERY 14 - 9
FUEL PUMP (Continued)

(b) If line is not kinked and pressure is low,
raise vehicle and disconnect fuel pressure line at
fuel filter/fuel pressure regulator (Fig. 15) . Three
fuel lines are attached to filter/regulator. Thefuel
pressure lineis attached to the right side of fil-
ter/regulator. It is also the most rearward of the
two (Fig. 15) .
(c) Install Special 5/16º Fuel Line Adapter Tool #
6539 between disconnected fuel line and filter/reg-
ulator fitting
(d) Attach 0±60 psi fuel pressure test gauge to
ªTº fitting on tool 6539.
Fig. 13 Test Port Cap LocationÐ4.7L V-8 Engine
1 - MOUNTING BOLTS (4)
2 - INJ.#7
3 - INJ.#5
4 - QUICK-CONNECT FITTING
5 - INJ.#3
6 - FUEL INJECTOR RAIL
7 - INJ.#1
8 - CONNECTOR TUBE
9 - INJ.#2
10 - INJ.#4
11 - INJ.#6
12 - INJ.#8
13 - PRESSURE TEST PORT CAP
Fig. 14 Fuel Pressure Test Gauge (Typical Gauge
Installation at Test Port)
1 - SERVICE (TEST) PORT
2 - FUEL PRESSURE TEST GAUGE
3 - FUEL RAIL
Fig. 15 Fuel Filter/Fuel Pressure Regulator Location
1 - FUEL SUPPLY LINE (TO FUEL RAIL)
2 - EVAP LINE
3 - FUEL RETURN LINE (MALE)
4 - FUEL PRESSURE LINE (FEMALE)
5 - FUEL FILTER/PRESSURE REGULATOR
6 - FUEL TANK
14 - 12 FUEL DELIVERYWJ
FUEL PUMP (Continued)

(8) Connect fuel return and pressure lines to fuel
pump module fittings (Fig. 16). Refer to Quick-Con-
nect Fittings.
(9) Install fuel tank. Refer to Fuel Tank Installa-
tion.
FUEL RAIL
DESCRIPTION
DESCRIPTION - 4.7L
The fuel injector rail is used to mount the fuel
injectors to the engine. It is mounted to the intake
manifold (Fig. 20).
DESCRIPTION - 4.0L
The fuel injector rail is used to mount the fuel
injectors to the engine (Fig. 21). On the 4.0L 6±cylin-
der engine, afuel damperis located near the center
of the fuel rail (Fig. 21).
OPERATION
OPERATION - 4.7L
High pressure fuel from the fuel pump is routed to
the fuel rail. The fuel rail then supplies the neces-
sary fuel to each individual fuel injector.
A fuel pressure test port is located on the fuel rail
(Fig. 20). A quick-connect fitting with a safety latch
is used to attach the fuel line to the fuel rail.
The fuel rail is not repairable.
OPERATION - 4.0L
The fuel injector rail supplies the necessary fuel to
each individual fuel injector.
High pressure fuel from the fuel pump is routed to
the fuel rail. The fuel rail then supplies the neces-
sary fuel to each individual fuel injector.
The fuel damper is used only to help control fuel
pressure pulsations. These pulsations are the result
of the firing of the fuel injectors. It isnot usedas a
fuel pressure regulator. The fuel pressure regulator is
not mountedto the fuel rail on any engine. It is
located near the front of the fuel tank above the rear
axle. Refer to Fuel Filter/Fuel Pressure Regulator in
this group for information.
A fuel pressure test port is located on the fuel rail
(Fig. 21). A quick-connect fitting with a safety latch
is used to attach the fuel line to the fuel rail.
The fuel rail is not repairable.
REMOVAL
REMOVAL - 4.7L
WARNING: THE FUEL SYSTEM IS UNDER CON-
STANT PRESSURE EVEN WITH ENGINE OFF.
BEFORE SERVICING FUEL RAIL, FUEL SYSTEM
PRESSURE MUST BE RELEASED.
Fig. 20 Fuel Injector RailÐ4.7L V-8 Engine
1 - MOUNTING BOLTS (4)
2 - INJ.#7
3 - INJ.#5
4 - QUICK-CONNECT FITTING
5 - INJ.#3
6 - FUEL INJECTOR RAIL
7 - INJ.#1
8 - CONNECTOR TUBE
9 - INJ.#2
10 - INJ.#4
11 - INJ.#6
12 - INJ.#8
13 - PRESSURE TEST PORT CAP
WJFUEL DELIVERY 14 - 15
FUEL PUMP MODULE (Continued)