2002 JEEP LIBERTY control panel

RECIRCULATION DOOR
ACTUATOR
REMOVAL
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, DISABLE THE AIRBAG SYSTEM BEFORE
ATTEMPTING ANY STEERING WHEEL, STEERING
COLUMN, OR INSTRUMENT PANEL COMPONENT
DIAGNOSIS OR SERVICE. DISCONNECT AND ISO-
LATE THE BATTERY NEGATIVE (GROUND) CABLE,
THEN WAIT TWO MINUTES FOR THE AIRBAG SYS-
TEM CAPACITOR TO DISCHARGE BEFORE PER-
FORMING FURTHER DIAGNOSIS OR SERVICE. THIS
IS THE ONLY SURE WAY TO DISABLE THE AIRBAG
SYSTEM. FAILURE TO TAKE THE PROPER PRE-
CAUTIONS COULD RESULT IN AN ACCIDENTAL
AIRBAG DEPLOYMENT AND POSSIBLE PERSONAL
INJURY.
(1) Disconnect and isolate the battery negative
cable.
(2) Unplug the vacuum harness connector from the
recirculation door actuator (Fig. 19).(3) Insert a trim stick or another suitable wide
flat-bladed tool into the latch hole on the HVAC
housing actuator mount (Fig. 20).
(4) Gently pry the actuator latch while pulling
firmly outwards on the actuator to remove the actua-
tor from the mount (Fig. 21).
(5) Disengage the hole on the end of the actuator
link from the hooked pin on the end of the recircula-
tion door lever.
(6) Remove the recirculation door vacuum actuator
from the vehicle.
INSTALLATION
(1) Install the recirculation door vacuum actuator
by slipping the arm on to the hole on the end of the
actuator link with the hooked pin on the end of the
panel/demist door lever.
(2) Snap the actuator back into its mount.
(3) Plug in the vacuum harness connector to the
recirculation door actuator.
(4) Connect the battery negative cable.
Fig. 19 RECIRCULATION DOOR ASSEMBLY
1- INSTRUMENT PANEL ELECTRICAL HARNESS MOUNTING
TABS
2- MOUNTING TAB
3- RECIRCULATION DOOR
4- MOUNTING TAB
5- RECIRCULATION DOOR ASSEMBLY
6- RECIRCULATION DOOR LEVER
Fig. 20 VACUUM ACTUATOR REMOVE/INSTALL -
TYPICAL
1 - ACTUATOR MOUNT LATCH HOLE
2 - TRIM STICK
3 - ACTUATOR LATCH
24 - 26 CONTROLSKJ

DISTRIBUTION
TABLE OF CONTENTS
page page
AIR OUTLETS
DESCRIPTION - DEMISTER OUTLETS.......29
REMOVAL - PANEL OUTLET BARRELS......29
INSTALLATION - PANEL OUTLET BARRELS . . . 29
BLOWER MOTOR
DESCRIPTION.........................30
OPERATION...........................30
DIAGNOSIS AND TESTING - BLOWER
MOTOR .............................30
REMOVAL.............................30
INSTALLATION.........................31
FLOOR CONSOLE DUCT
REMOVAL.............................31
INSTALLATION.........................31
FLOOR DUCT
REMOVAL.............................32
INSTALLATION.........................32
DEFROST - DEMISTER DUCT
REMOVAL - DEFROST DUCT/DEMISTER
ADAPTOR...........................32INSTALLATION - DEFROST/DEMISTER DUCT . 32
HVAC HOUSING
REMOVAL.............................33
DISASSEMBLY.........................34
ASSEMBLY............................34
INSTALLATION.........................34
BLEND DOOR
REMOVAL.............................35
INSTALLATION.........................35
MODE DOOR
REMOVAL
REMOVAL - DEFROST DOOR............35
REMOVAL - FLOOR - DEFROST DOOR....36
INSTALLATION
INSTALLATION - PANEL DOOR...........36
INSTALLATION - FLOOR - DEFROST DOO . . 37
RECIRC DOOR
REMOVAL.............................37
INSTALLATION.........................37
AIR OUTLETS
DESCRIPTION - DEMISTER OUTLETS
The side window demister outlets are integral to
the instrument panel end caps(Refer to 23 - BODY/
INSTRUMENT PANEL/INSTRUMENT PANEL END
CAP - REMOVAL) and (Refer to 23 - BODY/INSTRU-
MENT PANEL/INSTRUMENT PANEL END CAP -
REMOVAL).
REMOVAL - PANEL OUTLET BARRELS
(1) Use a trim stick or another suitable wide flat-
bladed tool to gently pry the panel outlet barrels out
of the panel outlet housing (Fig. 1). The barrel is
retained by a light snap fit.
INSTALLATION - PANEL OUTLET BARRELS
To install, position the barrel in the panel outlet
housing and press firmly until the barrel snaps into
place.
Fig. 1 DASH PANEL OUTLETS
1 - CENTER OUTLETS
2 - SIDE WINDOW DEMISTER OUTLETS
3 - SIDE OUTLETS
4 - WIRING FOR HVAC CONTROL ASSEMBLY
5 - WINDSHIELD DEFROSTER OUTLET
KJDISTRIBUTION 24 - 29

BLOWER MOTOR
DESCRIPTION
The blower motor and blower wheel are located in
the passenger side end of the HVAC housing, below
the glove box. The blower motor controls the velocity
of air flowing through the HVAC housing by spinning
a squirrel cage-type blower wheel within the housing
at the selected speed. The blower motor and wheel
can be removed from the housing inside the vehicle
without removing the dash or HVAC housing assem-
bly.
OPERATION
The blower motor will only operate when the igni-
tion switch is in the On position, and the A/C Heater
mode control switch knob is in any position, except
Off. The blower motor receives a fused battery feed
through the blower motor relay whenever the igni-
tion switch is in the On position. The blower motor
battery feed circuit is protected by a fuse in the
Power Distribution Center (PDC). Blower motor
speed is controlled by regulating the ground path
through the A/C Heater control blower motor switch
and the blower motor resistor.
The blower motor and blower motor wheel cannot
be repaired and, if faulty or damaged, they must be
replaced. The blower motor and blower wheel are ser-
viced only as a unit.
DIAGNOSIS AND TESTING - BLOWER MOTOR
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, DISABLE THE AIRBAG SYSTEM BEFORE
ATTEMPTING ANY STEERING WHEEL, STEERING
COLUMN, OR INSTRUMENT PANEL COMPONENT
DIAGNOSIS OR SERVICE. DISCONNECT AND ISO-
LATE THE BATTERY NEGATIVE (GROUND) CABLE,
THEN WAIT TWO MINUTES FOR THE AIRBAG SYS-
TEM CAPACITOR TO DISCHARGE BEFORE PER-
FORMING FURTHER DIAGNOSIS OR SERVICE. THIS
IS THE ONLY SURE WAY TO DISABLE THE AIRBAG
SYSTEM. FAILURE TO TAKE THE PROPER PRE-
CAUTIONS COULD RESULT IN AN ACCIDENTAL
AIRBAG DEPLOYMENT AND POSSIBLE PERSONAL
INJURY.
For circuit descriptions and diagrams, (Refer to
Appropriate Wiring Information). Possible causes of
an inoperative blower motor include:²Faulty fuse
²Faulty blower motor circuit wiring or wire har-
ness connectors
²Faulty blower motor resistor
²Faulty blower motor relay
²Faulty blower motor switch
²Faulty A/C Heater mode control switch
²Faulty blower motor.
Possible causes of the blower motor not operating
in all speeds include:
²Faulty blower motor switch
²Faulty blower motor resistor
²Faulty blower motor circuit wiring or wire har-
ness connectors.
VIBRATION
Possible causes of blower motor vibration include:
²Improper blower motor mounting
²Improper blower wheel mounting
²Blower wheel out of balance or bent
²Blower motor faulty.
NOISE
To verify that the blower is the source of the noise,
unplug the blower motor wire harness connector and
operate the HVAC system. If the noise goes away,
possible causes include:
²Foreign material in the HVAC housing
²Improper blower motor mounting
²Improper blower wheel mounting
²Blower motor faulty.
REMOVAL
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, DISABLE THE AIRBAG SYSTEM BEFORE
ATTEMPTING ANY STEERING WHEEL, STEERING
COLUMN, OR INSTRUMENT PANEL COMPONENT
DIAGNOSIS OR SERVICE. DISCONNECT AND ISO-
LATE THE BATTERY NEGATIVE (GROUND) CABLE,
THEN WAIT TWO MINUTES FOR THE AIRBAG SYS-
TEM CAPACITOR TO DISCHARGE BEFORE PER-
FORMING FURTHER DIAGNOSIS OR SERVICE. THIS
IS THE ONLY SURE WAY TO DISABLE THE AIRBAG
SYSTEM. FAILURE TO TAKE THE PROPER PRE-
CAUTIONS COULD RESULT IN AN ACCIDENTAL
AIRBAG DEPLOYMENT AND POSSIBLE PERSONAL
INJURY.
24 - 30 DISTRIBUTIONKJ

WARNING: (Refer to 24 - HEATING & AIR CONDI-
TIONING/PLUMBING - WARNING) and (Refer to 24 -
HEATING & AIR CONDITIONING/PLUMBING - CAU-
TION).
(1) Remove and disassemble the HVAC housing.
(Refer to 24 - HEATING & AIR CONDITIONING/
DISTRIBUTION/HVAC HOUSING - REMOVAL)
(Refer to 24 - HEATING & AIR CONDITIONING/
DISTRIBUTION/HVAC HOUSING - DISASSEMBLY)
(2) Insert a screwdriver into the latch hole (Fig. 7)
of the panel door pivot shaft to release the latch of
the panel door lever, and pull the lever out of the
pivot shaft from the outside of the upper half of the
HVAC housing.
(3) Remove the defrost door from the HVAC hous-
ing.
REMOVAL - FLOOR - DEFROST DOOR
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, DISABLE THE AIRBAG SYSTEM BEFORE
ATTEMPTING ANY STEERING WHEEL, STEERING
COLUMN, OR INSTRUMENT PANEL COMPONENT
DIAGNOSIS OR SERVICE. DISCONNECT AND ISO-
LATE THE BATTERY NEGATIVE (GROUND) CABLE,
THEN WAIT TWO MINUTES FOR THE AIRBAG SYS-
TEM CAPACITOR TO DISCHARGE BEFORE PER-
FORMING FURTHER DIAGNOSIS OR SERVICE. THIS
IS THE ONLY SURE WAY TO DISABLE THE AIRBAG
SYSTEM. FAILURE TO TAKE THE PROPER PRE-
CAUTIONS COULD RESULT IN AN ACCIDENTAL
AIRBAG DEPLOYMENT AND POSSIBLE PERSONAL
INJURY.WARNING: (Refer to 24 - HEATING & AIR CONDI-
TIONING/PLUMBING - WARNING) and (Refer to 24 -
HEATING & AIR CONDITIONING/PLUMBING - CAU-
TION).
(1) Remove and disassemble the HVAC housing.
(Refer to 24 - HEATING & AIR CONDITIONING/
DISTRIBUTION/HVAC HOUSING - REMOVAL)
(Refer to 24 - HEATING & AIR CONDITIONING/
DISTRIBUTION/HVAC HOUSING - DISASSEMBLY)
(2) Remove the floor door vacuum actuator from
the lower HVAC housing. (Refer to 24 - HEATING &
AIR CONDITIONING/CONTROLS/MODE DOOR
ACTUATOR - REMOVAL - FLOOR DOOR ACTUA-
TOR)
(3) Insert a screwdriver into the latch hole (Fig. 8)
of the floor door pivot shaft to release the latch of the
floor door lever, and pull the lever out of the pivot
shaft from the outside of the lower half of the HVAC
housing.
(4) Reach inside the lower half of the HVAC hous-
ing and carefully flex the floor door (Fig. 9) enough
so that the door pivot clears the pivot hole in the
housing.
(5) Remove the floor door from the HVAC housing.
INSTALLATION
INSTALLATION - PANEL DOOR
(1) Install the panel door in the HVAC housing.
(2) Snap the panel door pivot shaft over the latch
of the panel door lever.
(3) Attach the demist door and lever to the upper
HVAC housing. (Refer to 24 - HEATING & AIR CON-
Fig. 7 PANEL DOOR REMOVE/INSTALL
1 - DOOR PIVOT SHAFT
2 - LATCH HOLE
3 - CRANK ARM LATCH
4 - FLAT BLADE PRY TOOL
Fig. 8 FLOOR DOOR REMOVE/INSTALL (typical)
1 - DOOR PIVOT SHAFT
2 - LATCH HOLE
3 - CRANK ARM LATCH
4 - FLAT BLADE PRY TOOL
24 - 36 DISTRIBUTIONKJ
MODE DOOR (Continued)

DITIONING/DISTRIBUTION/MODE DOOR -
INSTALLATION - PANEL/DEMIST DOOR)
(4) Assemble the HVAC housing. (Refer to 24 -
HEATING & AIR CONDITIONING/DISTRIBUTION/
HVAC HOUSING - ASSEMBLY)
(5) Install the HVAC housing in the vehicle. (Refer
to 24 - HEATING & AIR CONDITIONING/DISTRI-
BUTION/HVAC HOUSING - INSTALLATION)
INSTALLATION - FLOOR - DEFROST DOO
(1) Install the floor-defrost door in the HVAC hous-
ing by placing the door in the lower housing.
(2) Assemble the HVAC housing. (Refer to 24 -
HEATING & AIR CONDITIONING/DISTRIBUTION/
HVAC HOUSING - ASSEMBLY)
(3) Install the floor door vacuum actuator in the
lower HVAC housing. (Refer to 24 - HEATING & AIR
CONDITIONING/CONTROLS/MODE DOOR
ACTUATOR - INSTALLATION - FLOOR DOOR
ACTUATOR)
(4) Install the HVAC housing in the vehicle. (Refer
to 24 - HEATING & AIR CONDITIONING/DISTRI-
BUTION/HVAC HOUSING - INSTALLATION)
RECIRC DOOR
REMOVAL
A recirculation door and vacuum actuator are used
only on models with the optional air conditioning sys-
tem.
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, DISABLE THE AIRBAG SYSTEM BEFOREATTEMPTING ANY STEERING WHEEL, STEERING
COLUMN, OR INSTRUMENT PANEL COMPONENT
DIAGNOSIS OR SERVICE. DISCONNECT AND ISO-
LATE THE BATTERY NEGATIVE (GROUND) CABLE,
THEN WAIT TWO MINUTES FOR THE AIRBAG SYS-
TEM CAPACITOR TO DISCHARGE BEFORE PER-
FORMING FURTHER DIAGNOSIS OR SERVICE. THIS
IS THE ONLY SURE WAY TO DISABLE THE AIRBAG
SYSTEM. FAILURE TO TAKE THE PROPER PRE-
CAUTIONS COULD RESULT IN AN ACCIDENTAL
AIRBAG DEPLOYMENT AND POSSIBLE PERSONAL
INJURY.
WARNING: IF THE VEHICLE IS EQUIPPED WITH AIR
CONDITIONING, REVIEW THE WARNINGS AND
CAUTIONS IN PLUMBING BEFORE PERFORMING
THE FOLLOWING OPERATION. (Refer to 24 - HEAT-
ING & AIR CONDITIONING/PLUMBING - WARNING)
(Refer to 24 - HEATING & AIR CONDITIONING/
PLUMBING - CAUTION)
(1) Remove the HVAC housing and disassemble.
(Refer to 24 - HEATING & AIR CONDITIONING/
DISTRIBUTION/HVAC HOUSING - REMOVAL)
(Refer to 24 - HEATING & AIR CONDITIONING/
DISTRIBUTION/HVAC HOUSING - DISASSEMBLY)
(2) Remove the four screws to remove the recircu-
lation door assembly. (Refer to 24 - HEATING & AIR
CONDITIONING/CONTROLS/RECIRCULATION
DOOR ACTUATOR - REMOVAL)
(3) Insert a screwdriver into the latch hole of the
panel door pivot shaft to release the latch of the
panel door lever and pull the lever out of the pivot
shaft from the outside of the upper half of the HVAC
housing.
INSTALLATION
(1) Guide the recirculation door lever through the
air intake grille of the HVAC housing while installing
the door in the housing.
(2) Assemble the HVAC housing. (Refer to 24 -
HEATING & AIR CONDITIONING/DISTRIBUTION/
HVAC HOUSING - ASSEMBLY)
(3) Install the HVAC housing in the vehicle. (Refer
to 24 - HEATING & AIR CONDITIONING/DISTRI-
BUTION/HVAC HOUSING - INSTALLATION)
(4) Install the recirculation door vacuum actuator
on the lower HVAC housing. (Refer to 24 - HEATING
& AIR CONDITIONING/CONTROLS/RECIRCULA-
TION DOOR ACTUATOR - INSTALLATION)
Fig. 9 FLOOR DOOR (typical)
1 - LOWER HVAC HOUSING
2 - PIVOT SHAFT
3 - CRANK ARM
4 - FLOOR DOOR
KJDISTRIBUTION 24 - 37
MODE DOOR (Continued)

evaporator outlet tube. Connect the accumulator inlet
tube refrigerant line coupler to the evaporator outlet
tube. (Refer to 24 - HEATING & AIR CONDITION-
ING/PLUMBING - STANDARD PROCEDURE - A/C
LINE COUPLERS)
(3) Tighten the accumulator retaining band screw
to 5 N´m (45 in. lbs.).
(4) Remove the tape or plugs from the refrigerant
line fittings on the suction line and the accumulator
outlet tube. Connect the suction line to the accumu-
lator outlet tube refrigerant line coupler. (Refer to 24
- HEATING & AIR CONDITIONING/PLUMBING -
STANDARD PROCEDURE - A/C LINE COUPLERS)
(5) Plug the wire harness connector into the low
pressure cycling clutch switch.
(6) Connect the battery negative cable.
(7) Evacuate the refrigerant system. (Refer to 24 -
HEATING & AIR CONDITIONING/PLUMBING -
STANDARD PROCEDURE - REFRIGERANT SYS-
TEM EVACUATE)
(8) Charge the refrigerant system. (Refer to 24 -
HEATING & AIR CONDITIONING/PLUMBING -
STANDARD PROCEDURE - REFRIGERANT SYS-
TEM CHARGE)NOTE: If the accumulator is replaced, add 120 mil-
liliters (4 fluid ounces) of refrigerant oil to the
refrigerant system. Use only refrigerant oil of the
type recommended for the compressor in the vehi-
cle. (Refer to 24 - HEATING & AIR CONDITIONING/
PLUMBING/REFRIGERANT OIL - DESCRIPTION)
HEATER CORE
DESCRIPTION
The heater core is located in the HVAC housing,
under the instrument panel. It is a heat exchanger
made of rows of tubes and fins and uses warm engine
coolant as its heat source.
OPERATION
Engine coolant is circulated through heater hoses
to the heater core at all times. As the coolant flows
through the heater core, heat removed from the
engine is transferred to the heater core fins and
tubes. Air directed through the heater core picks up
the heat from the heater core fins. The temperature
control door allows control of the heater output air
temperature by controlling how much of the air flow-
ing through the HVAC housing is directed through
the heater core. The blower motor speed controls the
volume of air flowing through the HVAC housing.
The heater core cannot be repaired and, if faulty or
damaged, it must be replaced. Refer to Cooling for
more information on the engine cooling system, the
engine coolant and the heater hoses.
REMOVAL
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, DISABLE THE AIRBAG SYSTEM BEFORE
ATTEMPTING ANY STEERING WHEEL, STEERING
COLUMN, OR INSTRUMENT PANEL COMPONENT
DIAGNOSIS OR SERVICE. DISCONNECT AND ISO-
LATE THE BATTERY NEGATIVE (GROUND) CABLE,
THEN WAIT TWO MINUTES FOR THE AIRBAG SYS-
TEM CAPACITOR TO DISCHARGE BEFORE PER-
FORMING FURTHER DIAGNOSIS OR SERVICE. THIS
IS THE ONLY SURE WAY TO DISABLE THE AIRBAG
SYSTEM. FAILURE TO TAKE THE PROPER PRE-
CAUTIONS COULD RESULT IN AN ACCIDENTAL
AIRBAG DEPLOYMENT AND POSSIBLE PERSONAL
INJURY.
Fig. 13 A/C LOW PRESSURE SWITCH
1 - WIRING HARNESS CONNECTOR
2 - A/C LOW PRESSURE SWITCH
3 - A/C LINE TO EVAPORATOR
4 - ACCUMULATOR MOUNTING BRACKET
5 - ACCUMULATOR
6 - A/C LOW PRESSURE LINE
24 - 52 PLUMBINGKJ
ACCUMULATOR (Continued)

EMISSIONS CONTROL
TABLE OF CONTENTS
page page
EMISSIONS CONTROL
DESCRIPTION
DESCRIPTION - EMISSION CONTROL
SYSTEM.............................1
DESCRIPTION - STATE DISPLAY TEST
MODE...............................2
DESCRIPTION - CIRCUIT ACTUATION TEST
MODE...............................2
DESCRIPTION - DIAGNOSTIC TROUBLE
CODES..............................2DESCRIPTION - TASK MANAGER.........17
DESCRIPTION - MONITORED SYSTEMS . . . 17
DESCRIPTION - TRIP DEFINITION........19
DESCRIPTION - COMPONENT MONITORS . . 19
DESCRIPTION - NON-MONITORED
CIRCUITS...........................20
DESCRIPTION - HIGH AND LOW LIMITS . . . 20
DESCRIPTION - LOAD VALUE...........20
OPERATION - TASK MANAGER............21
EVAPORATIVE EMISSIONS................24
EMISSIONS CONTROL
DESCRIPTION
DESCRIPTION - EMISSION CONTROL SYSTEM
The Powertrain Control Module (PCM) monitors
many different circuits in the fuel injection, ignition,
emission and engine systems. If the PCM senses a
problem with a monitored circuit often enough to
indicate an actual problem, it stores a Diagnostic
Trouble Code (DTC) in the PCM's memory. If the
code applies to a non-emissions related component or
system, and the problem is repaired or ceases to
exist, the PCM cancels the code after 40 warm-up
cycles. Diagnostic trouble codes that affect vehicle
emissions illuminate the Malfunction Indicator Lamp
(MIL). The MIL is displayed as an engine icon on the
instrument panel. Refer to Malfunction Indicator
Lamp (MIL) in this section.
Certain criteria must be met before the PCM
stores a DTC in memory. The criteria may be a spe-
cific range of engine RPM, engine temperature,
and/or input voltage to the PCM.
The PCM might not store a DTC for a monitored
circuit even though a malfunction has occurred. This
may happen because one of the DTC criteria for the
circuit has not been met.For example, assume the
diagnostic trouble code criteria requires the PCM to
monitor the circuit only when the engine operates
between 750 and 2000 RPM. Suppose the sensor's
output circuit shorts to ground when engine operates
above 2400 RPM (resulting in 0 volt input to the
PCM). Because the condition happens at an engine
speed above the maximum threshold (2000 rpm), the
PCM will not store a DTC.There are several operating conditions for which
the PCM monitors and sets DTC's. Refer to Moni-
tored Systems, Components, and Non-Monitored Cir-
cuits in this section.
Technicians must retrieve stored DTC's by connect-
ing the DRB scan tool (or an equivalent scan tool) to
the 16±way data link connector (Fig. 1).
NOTE: Various diagnostic procedures may actually
cause a diagnostic monitor to set a DTC. For
instance, pulling a spark plug wire to perform a
spark test may set the misfire code. When a repair
is completed and verified, connect the DRB scan
tool to the 16±way data link connector to erase all
DTC's and extinguish the MIL.
Fig. 1 DATA LINK CONNECTOR LOCATION
KJEMISSIONS CONTROL 25 - 1

DESCRIPTION - STATE DISPLAY TEST MODE
The switch inputs to the Powertrain Control Mod-
ule (PCM) have two recognized states; HIGH and
LOW. For this reason, the PCM cannot recognize the
difference between a selected switch position versus
an open circuit, a short circuit, or a defective switch.
If the State Display screen shows the change from
HIGH to LOW or LOW to HIGH, assume the entire
switch circuit to the PCM functions properly. Connect
the DRB scan tool to the data link connector and
access the state display screen. Then access either
State Display Inputs and Outputs or State Display
Sensors.
DESCRIPTION - CIRCUIT ACTUATION TEST
MODE
The Circuit Actuation Test Mode checks for proper
operation of output circuits or devices the Powertrain
Control Module (PCM) may not internally recognize.
The PCM attempts to activate these outputs and
allow an observer to verify proper operation. Most of
the tests provide an audible or visual indication of
device operation (click of relay contacts, fuel spray,
etc.). Except for intermittent conditions, if a device
functions properly during testing, assume the device,
its associated wiring, and driver circuit work cor-
rectly. Connect the DRB scan tool to the data link
connector and access the Actuators screen.
DESCRIPTION - DIAGNOSTIC TROUBLE CODES
A Diagnostic Trouble Code (DTC) indicates the
PCM has recognized an abnormal condition in the
system.Remember that DTC's are the results of a sys-
tem or circuit failure, but do not directly iden-
tify the failed component or components.
NOTE: For a list of DTC's, refer to the charts in this
section.
BULB CHECK
Each time the ignition key is turned to the ON
position, the malfunction indicator (check engine)
lamp on the instrument panel should illuminate for
approximately 2 seconds then go out. This is done for
a bulb check.
OBTAINING DTC'S USING DRB SCAN TOOL
(1) Connect the DRB scan tool to the data link
(diagnostic) connector. This connector is located in
the passenger compartment; at the lower edge of
instrument panel; near the steering column.
(2) Turn the ignition switch on and access the
ªRead Faultº screen.
(3) Record all the DTC's and ªfreeze frameº infor-
mation shown on the DRB scan tool.
(4) To erase DTC's, use the ªErase Trouble Codeº
data screen on the DRB scan tool.Do not erase any
DTC's until problems have been investigated
and repairs have been performed.
(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
P0030 (M) 1/1 O2 Sensor Heater Circuit
MalfunctionProblem detected in oxygen sensor heater relay circuit.
P0031 (M) 1/1 O2 Sensor Heater Circuit Low Problem detected in oxygen sensor heater relay circuit.
P0032 (M) 1/1 O2 Sensor Heater Circuit High Problem detected in oxygen sensor heater relay circuit.
P0036 (M) 1/2 O2 Sensor Heater Circuit
MalfunctionProblem detected in oxygen sensor heater relay circuit.
P0037 (M) 1/2 O2 Sensor Heater Circuit Low Problem detected in oxygen sensor heater relay circuit.
P0038 (M) 1/2 O2 Sensor Heater Circuit High Problem detected in oxygen sensor heater relay circuit.
P0043 (M) 1/3 O2 Sensor Heater Circuit Low Problem detected in oxygen sensor heater relay circuit.
P0044 (M) 1/3 O2 Sensor Heater Circuit High Problem detected in oxygen sensor heater relay circuit.
P0051 (M) 2/1 O2 Sensor Heater Circuit Low Problem detected in oxygen sensor heater relay circuit.
P0052 (M) 2/1 O2 Sensor Heater Circuit High Problem detected in oxygen sensor heater relay circuit.
25 - 2 EMISSIONS CONTROLKJ
EMISSIONS CONTROL (Continued)