Fuel pump JEEP LIBERTY 2002 KJ / 1.G Repair Manual

Fig. 27 FUEL PRESSURE REGULATOR/SENDING
UNIT ELECTRICAL CONNECTOR
1 - UPPER SECTION OF PUMP MODULE
2 - QUICK-CONNECT FITTINGS
3 - FUEL PRESSURE REGULATOR
4 - 4-WIRE ELECTRICAL CONNECTOR
5 - FUEL TANK CHECK (CONTROL) VALVE
Fig. 28 UPPER SECTION - FUEL PUMP MODULE
1 - UPPER SECTION - FUEL PUMP MODULE
2 - FUEL TANK CHECK (CONTROL) VALVE
Fig. 29 LOWER SECTION - FUEL PUMP MODULE
1 - LOWER SECTION - FUEL PUMP MODULE
2 - RELEASE LOCK AND TAB
3 - TENSION SPRINGS
Fig. 30 FUEL PUMP MODULE GUIDES (IN FUEL
TANK)
1 - FUEL TANK (INSIDE/LOWER)
2 - FUEL PUMP MODULE GUIDES
14 - 20 FUEL DELIVERYKJ
FUEL PUMP MODULE (Continued)

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 on the fuel tank mounted fuel pump module.
Refer to Fuel Pressure Regulator for additional infor-
mation.
The fuel rail is not repairable.
A quick-connect fitting with a safety latch is used
to attach the fuel line to the fuel rail.
3.7L
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 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
2.4L
WARNING: THE FUEL SYSTEM IS UNDER CON-
STANT PRESSURE EVEN WITH ENGINE OFF.
BEFORE SERVICING FUEL RAIL, FUEL SYSTEM
PRESSURE MUST BE RELEASED.
The fuel rail can be removed without removing the
intake manifold if the following procedures are fol-
lowed.(1) Remove fuel tank filler tube cap.
(2) Perform Fuel System Pressure Release Proce-
dure.
(3) Remove negative battery cable at battery.
(4) Remove air duct at throttle body.
(5) Disconnect fuel line latch clip and fuel line at
fuel rail. A special tool will be necessary for fuel line
disconnection. Refer to Quick-Connect Fittings.
(6) Remove necessary vacuum lines at throttle
body.
(7) Drain engine coolant and remove thermostat
and thermostat housing.
(8) Remove PCV hose and valve at valve cover.
(9) Remove 3 upper intake manifold mounting
bolts (Fig. 35), but only loosen 2 lower bolts about 2
turns.
(10) Disconnect 2 main engine harness connectors
at rear of intake manifold (Fig. 34).
(11) Disconnect 2 injection wiring harness clips at
harness mounting bracket (Fig. 35).
(12) Disconnect electrical connectors at all 4 fuel
injectors. To remove connector refer to (Fig. 37). Push
red colored slider away from injector (1). While push-
ing slider, depress tab (2) and remove connector (3)
from injector. The factory fuel injection wiring har-
ness is numerically tagged (INJ 1, INJ 2, etc.) for
injector position identification. If harness is not
tagged, note wiring location before removal.
(13) Remove 2 injection rail mounting bolts (Fig.
31).
Fig. 34 MAP SENSOR LOCATION-2.4L
1 - REAR OF INTAKE MANIFOLD
2 - MAP SENSOR
3 - ALIGNMENT PIN
4 - MOUNTING BOLT (TORX)
5 - ELECTRICAL CONNECTOR
6 - MAIN ENGINE HARNESS CONNECTORS
Fig. 35 FUEL RAIL MOUNTING-2.4L
1 - FUEL RAIL
2 - INJECTION HARNESS CLIPS
3 - LOWER MOUNTING HOLES
4 - UPPER MOUNTING HOLES
5 - INTAKE MANIFOLD
14 - 22 FUEL DELIVERYKJ
FUEL RAIL (Continued)

(14) If fuel injectors are to be removed, refer to
Fuel Injector Removal/Installation.
INSTALLATION
2.4L Engine
(1) If fuel injectors are to be installed, refer to Fuel
Injector Removal/Installation.
(2) Clean out fuel injector machined bores in
intake manifold.
(3) Apply a small amount of engine oil to each fuel
injector o-ring. This will help in fuel rail installation.
(4) Position fuel rail/fuel injector assembly to
machined injector openings in intake manifold.
(5) Guide each injector into cylinder head. Be care-
ful not to tear injector o-rings.
(6) Push fuel rail down until fuel injectors have
bottomed on shoulders.
(7) Install 2 fuel rail mounting bolts and tighten.
Refer to torque specifications.
(8) Connect electrical connectors at all fuel injec-
tors. To install connector, refer to (Fig. 37). Push con-
nector onto injector (1) and then push and lock red
colored slider (2). Verify connector is locked to injec-
tor by lightly tugging on connector.
(9) Snap 2 injection wiring harness clips (Fig. 35)
into brackets.
(10) Connect 2 main engine harness connectors at
rear of intake manifold (Fig. 34).
(11) Tighten 5 intake manifold mounting bolts.
Refer to Engine Torque Specifications.
(12) Install PCV valve and hose.
(13) Install thermostat and radiator hose. Fill with
coolant. Refer to Cooling.
(14) Connect necessary vacuum lines to throttle
body.
(15) Connect fuel line latch clip and fuel line to
fuel rail. Refer to Quick-Connect Fittings.
(16) Install air duct to throttle body.
(17) Connect battery cable to battery.
(18) Start engine and check for leaks.
3.7L Engine
(1) If fuel injectors are to be installed, refer to Fuel
Injector Removal/Installation.
(2) Clean out fuel injector machined bores in
intake manifold.
(3) Apply a small amount of engine oil to each fuel
injector o-ring. This will help in fuel rail installation.
(4) Position fuel rail/fuel injector assembly to
machined injector openings in cylinder head.
(5) Guide each injector into cylinder head. Be care-
ful not to tear injector o-rings.
(6) Pushrightside of fuel rail down until fuel
injectors have bottomed on cylinder head shoulder.Pushleftfuel rail down until injectors have bot-
tomed on cylinder head shoulder.
(7) Install 4 fuel rail mounting bolts and tighten.
Refer to torque specifications.
(8) Install 6 ignition coils. Refer to Ignition Coil
Removal/Installation.
(9) Connect electrical connectors to throttle body.
(10) Connect electrical connectors at all fuel injec-
tors. To install connector, refer to (Fig. 37). Push con-
nector onto injector (1) and then push and lock red
colored slider (2). Verify connector is locked to injec-
tor by lightly tugging on connector.
(11) Connect necessary vacuum lines to throttle
body.
(12) Connect fuel line latch clip and fuel line to
fuel rail. Refer to Quick-Connect Fittings.
(13) Install air box to throttle body.
(14) Install air duct to air box.
(15) Connect battery cable to battery.
(16) Start engine and check for leaks.
FUEL TANK
DESCRIPTION
The fuel tank is constructed of a plastic material.
Its main functions are for fuel storage and for place-
ment of the fuel pump module, and certain ORVR
components.
OPERATION
All models pass a full 360 degree rollover test
without fuel leakage. To accomplish this, fuel and
vapor flow controls are required for all fuel tank con-
nections.
A check (control) valve is mounted into the top sec-
tion of the 2±piece fuel pump module. Refer to Fuel
Tank Check Valve for additional information.
An evaporation control system is connected to the
fuel tank to reduce emissions of fuel vapors into the
atmosphere. When fuel evaporates from the fuel
tank, vapors pass through vent hoses or tubes to a
charcoal canister where they are temporarily held.
When the engine is running, the vapors are drawn
into the intake manifold. Certain models are also
equipped with a self-diagnosing system using a Leak
Detection Pump (LDP) and/or an ORVR system.
Refer to Emission Control System for additional
information.
14 - 24 FUEL DELIVERYKJ
FUEL RAIL (Continued)

REMOVAL
Fuel Tank Draining
WARNING: THE FUEL SYSTEM MAY BE UNDER
CONSTANT FUEL PRESSURE EVEN WITH THE
ENGINE OFF. THIS PRESSURE MUST BE
RELEASED BEFORE SERVICING FUEL TANK.
Two different procedures may be used to drain fuel
tank: removing fuel pump module access plate, or
using DRBtscan tool. Due to a one-way check valve
installed into the fuel fill opening fitting at the tank
(Fig. 38), the tank cannot be drained conventionally
at the fill cap.
The quickest draining procedure involves removing
fuel pump module access plate.
As an alternative procedure, the electric fuel pump
may be activated allowing tank to be drained at fuel
rail connection. Refer to DRB scan tool for fuel pump
activation procedures. Before disconnecting fuel line
at fuel rail, release fuel pressure. Refer to the Fuel
System Pressure Release Procedure for procedures.
Attach end of special test hose tool number 6541,
6539, 6631 or 6923 at fuel rail disconnection (tool
number will depend on model and/or engine applica-
tion). Position opposite end of this hose tool to an
approved gasoline draining station. Activate fuel
pump and drain tank until empty.
If electric fuel pump is not operating, fuel pump
module access plate must be removed for fuel drain-
ing. Refer to following procedures.Fuel tank removal will not be necessary for
fuel tank draining. Access for draining is from
rear cargo area.
(1) Open all windows in vehicle to allow for air
ventilation.
(2) Four cargo holdown clamps are located inside
the vehicle on the floor of the rear cargo area.
Remove the 2 rearward mounted clamps by drilling
out the clamp rivets.
(3) Fold carpeting forward to gain access to fuel
pump module access plate (Fig. 39).
(4) Remove 4 fuel pump module access plate nuts
(Fig. 39).
(5) While applying heat from a heat gun, carefully
pry up fuel pump module access plate. Take care not
to bend plate.
(6) Thoroughly clean area around top of pump
module to prevent contaminants from entering fuel
tank or fuel lines.
(7) Release fuel system pressure.
(8) Disconnect 2 fuel lines (Fig. 40) at fuel pump
module by pressing on tabs at side of fitting.
(9) Disconnect electrical connector (Fig. 40). Slide
red tab first to unlock, and push grey tab down for
removal.
(10) Disconnect ORVR hose (Fig. 40) at pump mod-
ule fitting.
Fig. 38 FUEL FILL CHECK VALVE
1 - ONE-WAY CHECK VALVE
2 - FUEL FILL FITTING
3 - SIDE OF FUEL TANK
Fig. 39 ACCESS PLATE
1 - FLOORPAN AT REAR
2 - FUEL PUMP MODULE ACCESS PLATE
3 - NUTS (4)
4 - OPENING TO PUMP MODULE
KJFUEL DELIVERY 14 - 25
FUEL TANK (Continued)

(11) Remove module lockring (Fig. 40) using a
brass drift and hammer (counter-clockwise).
(12) Carefully lift upper section of pump module
from fuel tank a few inches(lift upper section
from tank very slowly until rubber gasket can
be retained. If not, gasket will fall into fuel
tank).
(13) Using an approved gas holding tank, drain
fuel tank through fuel pump module opening.
Tank Removal
(1) After draining tank, temporarily place upper
section of fuel pump module back into fuel tank.
(2) Raise vehicle.
(3) If equipped, remove fuel tank skid plate and
tow hooks. Certain equipment packages will also
require removal of the trailer hitch. Refer to Tow
Hooks, Trailer Hitch or Skid Plate in 23, Body for
removal/installation procedures.
(4) Disconnect fuel filter ground strap.
(5) Disconnect fuel filter outlet line from body
retention clip located on frame near front/center of
tank (Fig. 41). Place a small screwdriver into side of
clip and twist for removal. Also disconnect Leak
Detection Pump (LDP) line (Fig. 41) from this clip.(6) Remove both 3/4º hoses at sides of Leak Detec-
tion Pump (LDP) (Fig. 41).
(7) Disconnect 3/4º flow management valve hose
(Fig. 41) at EVAP canister.
(8) Remove fuel fill hose clamp (Fig. 42) at fuel
tank, and disconnect hose from fuel tank.
(9) A third fuel line is attached to bottom of fuel
filter. The disconnection point (quick-connect fitting)
for this 3rd line is approximately 1 foot from front of
tank towards front of vehicle (Fig. 41). Clean connec-
tion point before disconnection. Disconnect by press-
ing on tabs at side of quick-connect fitting. Also
disconnect LDP vent line near this same point.
(10) Disconnect 2 vacuum/vent hoses from plastic
retention clip at left/front of fuel tank line (Fig. 41).
(11) Support tank with a hydraulic jack.
(12) Remove 4 fuel tank strap bolts (Fig. 41) (2 at
front of tank; 2 at rear of tank), and remove both
tank support straps (Fig. 41).
(13) Carefully lower tank a few inches and discon-
nect electrical connector at top of LDP (Fig. 43). To
disconnect electrical connector: Push upward on red
colored tab to unlock. Push on black colored tab
while removing connector.
Fig. 40 TOP OF FUEL PUMP MODULE
1 - LOCK RING
2 - ALIGNMENT NOTCH
3 - FUEL FILTER FITTINGS (2)
4 - ORVR SYSTEM HOSE AND CLAMP
5 - FLOW MANAGEMENT VALVE
6 - ELECTRICAL CONNECTOR
7 - LEAK DETECTION PUMP
8 - FUEL TANK CHECK (CONTROL) VALVE
9 - FUEL PUMP MODULE (UPPER SECTION)Fig. 41 FRONT OF FUEL TANK
1 - TANK MOUNTING BOLTS (4)
2 - TANK MOUNTING STRAPS (2)
3 - LEAK DETECTION PUMP (LDP)
4 - BODY RETENTION CLIP (CENTER)
5 - LDP HOSES
6 - HOSE TO FUEL MANAGEMENT VALVE
7 - BODY RETENTION CLIP (LEFT/FRONT)
8 - QUICK-CONECT FITTING
9 - LDP LINE
14 - 26 FUEL DELIVERYKJ
FUEL TANK (Continued)

(14) Continue lowering tank while guiding remain-
ing hoses and lines.
(15) If fuel tank is to be replaced, remove LDP,
fuel filter and fuel pump module from tank. Refer to
Leak Detection Pump, Fuel Filter and Fuel Pump
Module Removal/Installation procedures.
INSTALLATION
(1) If fuel tank is to be replaced, install LDP, fuel
filter and fuel pump module to tank. Refer to Leak
Detection Pump, Fuel Filter and Fuel Pump Module
Removal/Installation procedures.
(2) Position fuel tank to hydraulic jack.
(3) Raise tank while carefully guiding vent tubes/
hoses through frame rail and crossmember. Before
tank reaches body, connect electrical connector to
Leak Detection Pump (LDP).
(4) Continue raising tank until positioned to body.
(5) Attach two fuel tank mounting straps and 4
mounting bolts. Tighten bolts to 61 N´m (45 ft. lbs.)
torque.
(6) Connect 2 hoses to body retention clip at left/
front of tank.
(7) Connect fuel filter fuel line to main fuel line
(snaps together). After connecting, snap this line into
body retention clip. Also connect LDP vacuum hose
near this point.(8) Install fuel fill hose and hose clamp to fuel
tank fitting. Rotate hose until white painted index
mark on hose (Fig. 42) is located between alignment
notches on fuel tank fitting. Tighten clamp to 3.4
N´m (30 in. lbs.) torque.
(9) Connect fresh air and recirculation lines to fuel
fill tube.
(10) Connect 3/4º lines to Leak Detection Pump
(LDP).
(11) Connect 3/4º flow management valve hose to
EVAP canister.
(12) Snap remaining lines into body retention clip
at front/center of fuel tank.
(13) If equipped, install fuel tank skid plate,
trailer hitch and tow hooks. Refer to Tow Hooks,
Trailer Hitch or Skid Plate in 23, Body for removal/
installation procedures.
(14) Lower vehicle.
(15) Attach (snap on) 2 fuel filter fuel lines to top
of fuel pump module.
(16) Install electrical connector to top of fuel pump
module.
(17) Connect negative battery cable to battery.
(18) Fill fuel tank with fuel.
(19) Start engine and check for fuel leaks near top
of module.
(20) Apply silicone sealant to bottom of fuel pump
module metal access plate.
Fig. 42 FUEL FILL HOSE AT TANK
1 - FUEL FILL HOSE AT TANK
2 - HOSE CLAMP
3 - WHITE PAINTED INDEX MARK
4 - ALIGNMENT NOTCHES
5 - LEFT SIDE OF FUEL TANK
6 - FUEL FILL FITTINGFig. 43 LDP ELECTRICAL CONNECTOR
1 - LEAK DETECTION PUMP (LDP)
2 - ELECTRICAL CONNECTOR
3 - FUEL FILTER
KJFUEL DELIVERY 14 - 27
FUEL TANK (Continued)

(21) Install fuel pump module metal access plate
and 4 nuts. Tighten nuts to 3 N´m (26 in. lbs.)
torque.
(22) Position carpet and install 2 new cargo clamp
rivets into each cargo holdown clamp.
FUEL TANK CHECK VALVE
DESCRIPTION
The fuel tank is equipped with a check valve. The
valve (also referred to as a control valve) is located in
the top section of the fuel pump module assembly
(Fig. 1).
OPERATION
The fuel tank check valve (also referred to as
either a control valve, one-way check valve or float
valve) will prevent fuel flow through the fuel tank
vent in the event of an accidental vehicle rollover. It
is also used as a part of the ORVR system. The
EVAP canister and ORVR system draw fuel vapors
from the fuel tank through this valve. Refer to ORVR
in Emissions for additional information.
The valve may be serviced by replacing the upper
section of the fuel pump module assembly.
REMOVAL
The fuel tank check (control) valve is attached into
the top section of the fuel pump module (Fig. 44). If
replacement is necessary, the top section of the fuel
pump module must be replaced. Refer to Fuel Pump
Module Removal/Installation.
INSTALLATION
The fuel tank check (control) valve is attached to
the top section of the fuel pump module. If replace-
ment is necessary, the top section of the fuel pump
module must be replaced. Refer to Fuel Pump Mod-
ule Removal/Installation.
INLET FILTER
REMOVAL
The fuel pump inlet filter is located on the bottom/
side of the lower fuel pump module section (Fig. 45).
The fuel pump module assembly is located in the fuel
tank.
(1) Remove lower section of fuel pump module.
Refer to Fuel Pump Module Removal/Installation.
(2) Remove filter by prying from pump module
with 2 small screwdrivers. Filter is snapped to mod-
ule with 2 release tabs (Fig. 45).
(3) Clean filter entrance into pump module open-
ing.
INSTALLATION
(1) Snap new filter to bottom of fuel pump module.
(2) Install lower section of fuel pump module.
Refer to Fuel Pump Module Removal/Installation.
Fig. 44 UPPER SECTION - FUEL PUMP MODULE
1 - UPPER SECTION - FUEL PUMP MODULE
2 - FUEL TANK CHECK (CONTROL) VALVE
Fig. 45 INLET FILTER
1 - INLET FILTER
2 - RELEASE TABS (2)
3 - BOTTOM OF FUEL PUMP MODULE
14 - 28 FUEL DELIVERYKJ
FUEL TANK (Continued)

FUEL INJECTION
TABLE OF CONTENTS
page page
FUEL INJECTION
DESCRIPTION.........................29
ACCELERATOR PEDAL
REMOVAL.............................29
INSTALLATION.........................30
CRANKSHAFT POSITION SENSOR
DESCRIPTION.........................30
OPERATION...........................31
REMOVAL.............................31
INSTALLATION.........................32
FUEL INJECTOR
DESCRIPTION.........................33
OPERATION
OPERATION - FUEL INJECTOR..........33
OPERATION - PCM OUTPUT............33
DIAGNOSIS AND TESTING - FUEL INJECTOR . 33
REMOVAL.............................34
INSTALLATION.........................34
FUEL PUMP RELAY
DESCRIPTION.........................34
OPERATION...........................34
DIAGNOSIS AND TESTING - FUEL PUMP
RELAY..............................34
REMOVAL.............................34
INSTALLATION.........................34
IDLE AIR CONTROL MOTOR
DESCRIPTION.........................35
OPERATION...........................35
REMOVAL.............................36INSTALLATION.........................36
INTAKE AIR TEMPERATURE SENSOR
DESCRIPTION.........................36
OPERATION...........................36
REMOVAL.............................37
INSTALLATION.........................38
MAP SENSOR
DESCRIPTION.........................38
OPERATION...........................38
REMOVAL.............................39
INSTALLATION.........................40
OXYGEN SENSOR
DESCRIPTION.........................40
OPERATION...........................40
REMOVAL.............................41
INSTALLATION.........................43
THROTTLE BODY
DESCRIPTION.........................43
OPERATION...........................43
REMOVAL.............................43
INSTALLATION.........................44
THROTTLE CONTROL CABLE
REMOVAL.............................45
INSTALLATION.........................46
THROTTLE POSITION SENSOR
DESCRIPTION.........................47
OPERATION...........................47
REMOVAL.............................47
INSTALLATION.........................48
FUEL INJECTION
DESCRIPTION
The Powertrain Control Module (PCM) operates
the fuel injection system. Refer to Powertrain Control
Module in Electronic Control Modules for informa-
tion.
ACCELERATOR PEDAL
REMOVAL
The accelerator pedal is serviced as a complete
assembly including the bracket.The accelerator pedal is connected to the upper
part of the accelerator pedal arm by a plastic
retainer (clip) (Fig. 1). This plastic retainer snaps
into the top of the accelerator pedal arm.
(1) From inside the vehicle, hold up accelerator
pedal. Remove plastic cable retainer (clip) and throt-
tle cable core wire from upper end of accelerator
pedal arm (Fig. 1). Plastic cable retainer (clip) snaps
into pedal arm.
(2) Remove 2 accelerator pedal mounting bracket
nuts. Remove accelerator pedal assembly.
KJFUEL INJECTION 14 - 29

REMOVAL
(1) Remove fuel rail. Refer to Fuel Injector Rail
Removal.
(2) Disconnect clip(s) that retain fuel injector(s) to
fuel rail (Fig. 10).
INSTALLATION
(1) Install fuel injector(s) into fuel rail assembly
and install retaining clip(s).
(2) If same injector(s) is being reinstalled, install
new o-ring(s).
(3) Apply a small amount of clean engine oil to
each injector o-ring. This will aid in installation.
(4) Install fuel rail. Refer to Fuel Rail Installation.
(5) Start engine and check for fuel leaks.
FUEL PUMP RELAY
DESCRIPTION
The 5±pin, 12±volt, fuel pump relay is located in
the Power Distribution Center (PDC). Refer to the
label on the PDC cover for relay location.
OPERATION
The Powertrain Control Module (PCM) energizes
the electric fuel pump through the fuel pump relay.
The fuel pump relay is energized by first applying
battery voltage to it when the ignition key is turnedON, and then applying a ground signal to the relay
from the PCM.
Whenever the ignition key is turned ON, the elec-
tric fuel pump will operate. But, the PCM will shut-
down the ground circuit to the fuel pump relay in
approximately 1±3 seconds unless the engine is oper-
ating or the starter motor is engaged.
DIAGNOSIS AND TESTING - FUEL PUMP
RELAY
For procedures, refer to ASD Relay Diagnosis and
Testing in the Ignition section.
REMOVAL
The fuel pump relay is located in the Power Distri-
bution Center (PDC) (Fig. 11). Refer to label on PDC
cover for relay location.
(1) Remove PDC cover.
(2) Remove relay from PDC.
(3) Check condition of relay terminals and PDC
connector terminals for damage or corrosion. Repair
if necessary before installing relay.
(4) Check for pin height (pin height should be the
same for all terminals within the PDC connector).
Repair if necessary before installing relay.
INSTALLATION
The fuel pump relay is located in the Power Distri-
bution Center (PDC). Refer to label on PDC cover for
relay location.
(1) Install relay to PDC.
(2) Install cover to PDC.
Fig. 10 INJECTOR RETAINING CLIP
1 - PLIERS
2 - INJECTOR CLIP
3 - FUEL INJECTOR
4 - FUEL RAIL - TYPICAL
Fig. 11 POWER DISTRIBUTION CENTER (PDC)
1 - BATTERY
2 - PDC
3 - PDC COVER
14 - 34 FUEL INJECTIONKJ
FUEL INJECTOR (Continued)

(M)Malfunction Indicator Lamp (MIL) illuminated during engine operation if this DTC was recorded
(depending if required by CARB and/or EPA). MIL is displayed as an engine icon on instrument panel.
(G)Generator lamp illuminated
Generic Scan
Tool P-CodeDRB Scan Tool Display Brief Description of DTC
P0135 (M) 1/1 O2 Sensor Heater Failure Oxygen sensor heater element malfunction.
P0136 (M) 1/2 O2 Sensor Heater Circuit
MalfunctionOxygen sensor heater element malfunction.
P0137 (M) 1/2 O2 Sensor Shorted To Ground Oxygen sensor input voltage maintained below normal
operating range.
P0138 (M) 1/2 O2 Sensor Shorted To Voltage Oxygen sensor input voltage maintained above normal
operating range.
P0139 (M) 1/2 O2 Sensor Slow Response Oxygen sensor response not as expected.
P0140 (M) 1/2 O2 Sensor Stays at Center Neither rich or lean condition is detected from the oxygen
sensor.
P0141 (M) 1/2 O2 Sensor Heater Failure Oxygen sensor heater element malfunction.
P0143 (M) 1/3 O2 Sensor Shorted To Ground Oxygen sensor input voltage maintained below normal
operating range.
P0144 (M) 1/3 O2 Sensor Shorted To Voltage Oxygen sensor input voltage maintained above normal
operating range.
P0145 (M) 1/3 O2 Sensor Slow Response Oxygen sensor response slower than minimum required
switching frequency.
P0146 (M) 1/3 O2 Sensor Stays at Center Neither rich or lean condition is detected from the oxygen
sensor.
P0147 (M) 1/3 O2 Sensor Heater Failure Oxygen sensor heater element malfunction.
P0151 (M) 2/1 O2 Sensor Shorted To Ground Oxygen sensor input voltage maintained below normal
operating range.
P0152 (M) 2/1 O2 Sensor Shorted To Voltage Oxygen sensor input voltage sustained above normal
operating range.
P0153 (M) 2/1 O2 Sensor Slow Response Oxygen sensor response slower than minimum required
switching frequency.
P0154 (M) 2/1 O2 Sensor Stays at Center Neither rich or lean condition is detected from the oxygen
sensor.
P0155 (M) 2/1 O2 Sensor Heater Failure Oxygen sensor heater element malfunction.
P0157 (M) 2/2 O2 Sensor Shorted To Ground Oxygen sensor input voltage maintained below normal
operating range.
P0158 (M) 2/2 O2 Sensor Shorted To Voltage Oxygen sensor input voltage maintained above normal
operating range.
P0159 2/2 O2 Sensor Slow Response Oxygen sensor response slower than minimum required
switching frequency.
P0160 (M) 2/2 O2 Sensor Stays at Center Neither rich or lean condition is detected from the oxygen
sensor.
P0161 (M) 2/2 O2 Sensor Heater Failure Oxygen sensor heater element malfunction.
PO165 Starter Relay Circuit Problem detected in starter relay circuit.
P0168 Decreased Engine Performance Due
To High Injection Pump Fuel TempFuel temperature is above the engine protection limit.
Engine power will be derated.
P0171 (M) 1/1 Fuel System Lean A lean air/fuel mixture has been indicated by an
abnormally rich correction factor.
25 - 4 EMISSIONS CONTROLKJ
EMISSIONS CONTROL (Continued)