2002 ISUZU AXIOM heater

0A±12
GENERAL INFORMATION
Abbreviations Charts
List of automotive abbreviations which may be used
in this manual
A Ð Ampere(s)
ABS Ð Antilock Brake System
AC Ð Alternating Current
A/C Ð Air Conditioning
ACCEL Ð Accelerator
ACC Ð Accessory
ACL Ð Air Cleaner
Adj Ð Adjust
A/F Ð Air Fuel Ratio
AIR Ð Secondary Air Injection System
Alt Ð Altitude
AMP Ð Ampere(s)
ANT Ð Antenna
ASM Ð Assembly
A/T Ð Automatic Transmission/Transaxle
ATDC Ð After Top Dead Center
ATF Ð Automatic Transmission Fluid
Auth Ð Authority
Auto Ð Automatic
BARO Ð Barometric Pressure
Bat Ð Battery
B+ Ð Battery Positive Voltage
Bbl Ð Barrel
BHP Ð Brake Horsepower
BPT Ð Backpressure Transducer
BTDC Ð Before Top Dead Center

C Ð Degrees Celsius
CAC Ð Charge Air Cooler
Calif Ð California
cc Ð Cubic Centimeter
CID Ð Cubic Inch Displacement
CKP Ð Crankshaft Position
CL Ð Closed Loop
CLCC Ð Closed Loop Carburetor Control
CMP Ð Camshaft Position
CO Ð Carbon Monoxide
Coax Ð Coaxial
Conn Ð Connector
Conv Ð Converter
Crank Ð Crankshaft
Cu. In. Ð Cubic Inch
CV Ð Constant Velocity
Cyl Ð Cylinder(s)
DI Ð Distributor Ignition
Diff Ð Differential
Dist Ð Distributor
DLC Ð Data Link Connector
DOHC Ð Double Overhead Camshaft
DTC Ð Diagnostic Trouble Code
DTM Ð Diagnostic Test Mode
DTT Ð Diagnostic Test Terminal
DVM Ð Digital Voltmeter (10 meg.)
DVOM Ð Digital Volt Ohmmeter
EBCM Ð Electronic Brake Control Module
ECM Ð Engine Control Module
ECT Ð Engine Coolant Temperature
EEPROM Ð Electronically Erasable Programmable
Read Only Memory
EGR Ð Exhaust Gas Recirculation
EI Ð Electronic Ignition
ETR Ð Electronically Tuned Receiver
EVAP Ð Evaporation EmissionExh Ð Exhaust

F Ð Degrees Fahrenheit
Fed Ð Federal (All States Except Calif.)
FF Ð Front Drive Front Engine
FL Ð Fusible Link
FLW Ð Fusible Link Wire
FP Ð Fuel Pump
FRT Ð Front
ft Ð Foot
FWD Ð Front Wheel Drive
4WD Ð Four Wheel Drive
4 x 4 Ð Four Wheel Drive
4 A/T Ð Four Speed Automatic Transmission/Transaxle
Gal Ð Gallon
GEN Ð Generator
GND Ð Ground
Gov Ð Governor
g Ð Gram
Harn Ð Harness
HC Ð Hydrocarbons
HD Ð Heavy Duty
Hg Ð Hydrargyrum (Mercury)
HiAlt Ð High Altitude
HO2S Ð Heated Oxygen Sensor
HVAC Ð Heater±Vent±Air±Conditioning
IAC Ð Idle Air Control
IAT Ð Intake Air Temperature
IC Ð Integrated Circuit / Ignition Control
ID Ð Identification / Inside Diameter
IGN Ð Ignition
INJ Ð Injection
IP Ð Instrument Panel
IPC Ð Instrument Panel Cluster
Int Ð Intake
ISC Ð Idle Speed Control
J/B Ð Junction Block
kg Ð Kilograms
km Ð Kilometers
km/h Ð Kilometer per Hour
kPa Ð Kilopascals
kV Ð Kilovolts (thousands of volts)
kW Ð Kilowatts
KS Ð Knock Sensor
L Ð Liter
lb ft Ð Foot Pounds
lb in Ð Inch Pounds
LF Ð Left Front
LH Ð Left Hand
LR ÐLeft Rear
LS Ð Left Side
LWB Ð Long Wheel Base
L±4 Ð In±Line Four Cylinder Engine
MAF Ð Mass Air Flow
MAN Ð Manual
MAP Ð Manifold Absolute Pressure
Max Ð Maximum
MC Ð Mixture Control
MFI Ð Multiport Fuel Injection
MIL Ð Malfunction Indicator Lamp
Min Ð Minimum
mm Ð Millimeter
MPG Ð Miles Per Gallon
MPH Ð Miles Per Hour
M/T Ð Manual Transmission/Transaxle
MV Ð Millivolt

HEATING, VENTILATION AND AIR CONDITIONING (HVAC)
1A±1
AXIOM
HEATING, VENTILATION AND AIR
CONDITIONING (HVAC)
HVAC SYSTEMS
CONTENTS
Service Precaution 1A±3. . . . . . . . . . . . . . . . . . . . . .
Heating and Ventilation System 1A±3. . . . . . . . . . .
General Description 1A±3. . . . . . . . . . . . . . . . . . . . .
Heater Unit 1A±6. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Heater Unit and Associated Parts 1A±6. . . . . . . .
Removal 1A±6. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Installation 1A±6. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Heater Core and / or Mode Door 1A±7. . . . . . . . . .
Disassembled View 1A±7. . . . . . . . . . . . . . . . . . . .
Removal 1A±8. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Inspection 1A±8. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Installation 1A±8. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Heater Mode Control Link Unit 1A±9. . . . . . . . . . . .
Disassembled View 1A±9. . . . . . . . . . . . . . . . . . . .
Removal 1A±9. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Installation 1A±10. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Heater Temperature Control Link Unit 1A±11. . . . . .
Disassembled View 1A±11. . . . . . . . . . . . . . . . . . . .
Removal 1A±11. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Installation 1A±11. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Blower Assembly 1A±12. . . . . . . . . . . . . . . . . . . . . . . .
Blower Assembly and Associated Parts 1A±12. .
Removal 1A±12. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Installation 1A±12. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Blower Link Unit and / or Mode door 1A±13. . . . . . .
Disassembled View 1A±13. . . . . . . . . . . . . . . . . . . .
Removal 1A±13. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Installation 1A±14. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Blower Motor 1A±15. . . . . . . . . . . . . . . . . . . . . . . . . . .
Blower Motor and Associated Parts 1A±15. . . . . .
Removal 1A±15. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Installation 1A±15. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Rear Heater Duct, Defroster Nozzle and
Ventilation Duct 1A±16. . . . . . . . . . . . . . . . . . . . . . . . .
Rear Heater Duct, Defroster Nozzle,
Ventilation Duct and Associated Parts 1A±16. . .
Removal 1A±16. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Installation 1A±17. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Air Conditioning System 1A±18. . . . . . . . . . . . . . . . . .
General Description 1A±18. . . . . . . . . . . . . . . . . . . . .
Diagnosis 1A±24. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Air Conditioning System 1A±31. . . . . . . . . . . . . . . . . . Individual Inspection 1A±31. . . . . . . . . . . . . . . . . . . . .
General Repair Procedure 1A±31. . . . . . . . . . . . . .
Leak Check 1A±33. . . . . . . . . . . . . . . . . . . . . . . . . . .
Compressor Assembly 1A±38. . . . . . . . . . . . . . . . . . .
Compressor Assembly and Associated
Parts (6VE1) 1A±38. . . . . . . . . . . . . . . . . . . . . . . . .
Removal 1A±38. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Installation 1A±39. . . . . . . . . . . . . . . . . . . . . . . . . . . .
New Compressor Installation 1A±39. . . . . . . . . . . .
Condenser Assembly 1A±40. . . . . . . . . . . . . . . . . . . .
Condenser Assembly and Associated
Parts 1A±40. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Removal 1A±40. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Installation 1A±41. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Condenser Fan Motor 1A±42. . . . . . . . . . . . . . . . . . . .
Condenser Fan Motor and Associated
Parts 1A±42. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Removal 1A±42. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Installation 1A±42. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Receiver / Drier 1A±43. . . . . . . . . . . . . . . . . . . . . . . . .
Receiver / Drier and Associated Parts 1A±43. . . .
Removal 1A±43. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Installation 1A±43. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Pressure Switch 1A±44. . . . . . . . . . . . . . . . . . . . . . . . .
Pressure Switch and Associated Parts 1A±44. . .
Removal 1A±44. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Installation 1A±44. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Evaporator Assembly 1A±45. . . . . . . . . . . . . . . . . . . .
Evaporator Assembly and Associated
Parts 1A±45. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Removal 1A±45. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Installation 1A±46. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Duct Sensor, Evaporator Core and/or
Expansion Valve 1A±47. . . . . . . . . . . . . . . . . . . . . . . .
Disassembled View 1A±47. . . . . . . . . . . . . . . . . . . .
Removal 1A±47. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Installation 1A±48. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Refrigerant Line 1A±49. . . . . . . . . . . . . . . . . . . . . . . . .
Refrigerant Line and Associated Parts 1A±49. . . .
Removal 1A±49. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Installation 1A±50. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Main Data And Specifications 1A±51. . . . . . . . . . . . .

1A±2
HEATING, VENTILATION AND AIR CONDITIONING (HVAC)
Compressor 1A±53. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Service Precaution 1A±53. . . . . . . . . . . . . . . . . . . .
General Description 1A±53. . . . . . . . . . . . . . . . . . . . . .
Diagnosis 1A±54. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Magnetic Clutch Assembly (DKV-14G Type) 1A±55
Parts Location View 1A±55. . . . . . . . . . . . . . . . . . . .
Removal 1A±55. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Inspection and Repair 1A±57. . . . . . . . . . . . . . . . . .
Installation 1A±57. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Compressor Oil 1A±59. . . . . . . . . . . . . . . . . . . . . . . . .
Oil Specification 1A±59. . . . . . . . . . . . . . . . . . . . . . .
Handling of Oil 1A±59. . . . . . . . . . . . . . . . . . . . . . . .
Compressor Oil Check 1A±59. . . . . . . . . . . . . . . . .
Checking and Adjusting Oil Quantity for
Used Compressor 1A±59. . . . . . . . . . . . . . . . . . . . .
Checking and Adjusting for Compressor
Replacement 1A±60. . . . . . . . . . . . . . . . . . . . . . . . .
Contamination of Compressor Oil 1A±60. . . . . . . .
Oil Return Operation 1A±60. . . . . . . . . . . . . . . . . . .
Replacement of Component Parts 1A±60. . . . . . .
Main Data and Specifications 1A±61. . . . . . . . . . . . .
Special Tools 1A±63. . . . . . . . . . . . . . . . . . . . . . . . . .
Automatic Air Conditioning System 1A±64. . . . . . . .
General Description 1A±64. . . . . . . . . . . . . . . . . . . . . .
Automatic Air Conditioner Parts
Configuration 1A±64. . . . . . . . . . . . . . . . . . . . . . . . .
Circuit Diagram 1A±65. . . . . . . . . . . . . . . . . . . . . . .
Functions and Features 1A±70. . . . . . . . . . . . . . . .
Automatic Air Conditioner Block Diagram 1A±71.
Control Panel Layout 1A±72. . . . . . . . . . . . . . . . . . .
Air Control Functions 1A±73. . . . . . . . . . . . . . . . . . .
Control Panel Switch Operation 1A±74. . . . . . . . .
Overview of Construction, Movement and
Control of Major Parts of Automatic Air
Conditioner System 1A±77. . . . . . . . . . . . . . . . . . .
Overview of Automatic Control of Automatic
Air Conditioner 1A±81. . . . . . . . . . . . . . . . . . . . . . .
Automatic Air Conditioning System 1A±82. . . . . .
Troubleshooting 1A±86. . . . . . . . . . . . . . . . . . . . . . . . .
Troubleshooting, Its Overview and
Procedures 1A±86. . . . . . . . . . . . . . . . . . . . . . . . . .
Auto Air Conditioner Control Unit Power
Supply Diagnosis 1A±87. . . . . . . . . . . . . . . . . . . . . Performance and Movement checklist for
Automatic Air Conditioner Related Parts 1A±89.
Troubleshooting With Self-Diagnosis
Function 1A±91. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Inspection By Failed Location 1A±97. . . . . . . . . . . . .
Inspection of the Sensors 1A±97. . . . . . . . . . . . . . .
Inspection of the Intake Actuator System 1A±101.
Inspection of the Mix Actuator System 1A±104. . . .
Inspection of the Mode Actuator System 1A±107. .
Inspection of the Fan Motor System 1A±110. . . . . .
Inspection of the Magnetic Clutch System 1A±115
Individual Inspection 1A±118. . . . . . . . . . . . . . . . . . .
On-Vehicle Service 1A±121. . . . . . . . . . . . . . . . . . . . . .
Power Transistor 1A±121. . . . . . . . . . . . . . . . . . . . . .
Removal 1A±121. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Installation 1A±121. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Automatic Heater/Air Conditioner Control
Unit 1A±121. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Removal 1A±121. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Installation 1A±121. . . . . . . . . . . . . . . . . . . . . . . . . . . .
In Car Sensor 1A±122. . . . . . . . . . . . . . . . . . . . . . . . .
Removal 1A±122. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Installation 1A±122. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Ambient Sensor 1A±122. . . . . . . . . . . . . . . . . . . . . . .
Removal 1A±122. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Installation 1A±122. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Sun Sensor 1A±123. . . . . . . . . . . . . . . . . . . . . . . . . . .
Removal 1A±123. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Installation 1A±123. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Duct Sensor 1A±123. . . . . . . . . . . . . . . . . . . . . . . . . .
Removal 1A±123. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Installation 1A±123. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Mode Actuator 1A±124. . . . . . . . . . . . . . . . . . . . . . . .
Removal 1A±124. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Installation 1A±124. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Mix Actuator 1A±124. . . . . . . . . . . . . . . . . . . . . . . . . .
Removal 1A±124. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Installation 1A±124. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Intake Actuator 1A±125. . . . . . . . . . . . . . . . . . . . . . . .
Removal 1A±125. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Installation 1A±125. . . . . . . . . . . . . . . . . . . . . . . . . . . .

HEATING, VENTILATION AND AIR CONDITIONING (HVAC)
1A±3
Service Precaution
WARNING: THIS VEHICLE HAS A SUPPLEMENTAL
RESTRAINT SYSTEM (SRS). REFER TO THE SRS
COMPONENT AND WIRING LOCATION VIEW IN
ORDER TO DETERMINE WHETHER YOU ARE
PERFORMING SERVICE ON OR NEAR THE SRS
COMPONENTS OR THE SRS WIRING. WHEN YOU
ARE PERFORMING SERVICE ON OR NEAR THE SRS
COMPONENTS OR THE SRS WIRING, REFER TO
THE SRS SERVICE INFORMATION. FAILURE TO
FOLLOW WARNINGS COULD RESULT IN POSSIBLE
AIR BAG DEPLOYMENT, PERSONAL INJURY, OR
OTHERWISE UNNEEDED SRS SYSTEM REPAIRS.CAUTION: Always use the correct fastener in the
proper location. When you replace a fastener, use
ONLY the exact part number for that application.
ISUZU will call out those fasteners that require a
replacement after removal. ISUZU will also call out
the fasteners that require thread lockers or thread
sealant. UNLESS OTHERWISE SPECIFIED, do not
use supplemental coatings (Paints, greases, or other
corrosion inhibitors) on threaded fasteners or
fastener joint interfaces. Generally, such coatings
adversely affect the fastener torque and the joint
clamping force, and may damage the fastener. When
you install fasteners, use the correct tightening
sequence and specifications. Following these
instructions can help you avoid damage to parts and
systems.
Heating and Ventilation System
General Description
Heater
When the engine is warming up, the warmed engine
coolant is sent into the heater core. The heater system
supplies warm air into the passenger compartment to
warm it up.
Outside air is circulated through the heater core of the
heater unit and then into the passenger compartment. By
controlling the mixture of outside air and heater core air,
the most comfortable passenger compartment
temperature can be selected and maintained.
The temperature of warm air sent to the passenger
compartment is controlled by the temperature control
knob. This knob acts to open and close the air mix door,
thus controlling the amount of air passed through the
heater core.The air selector switch (Mode SW), with its different
modes, also allows you to select and maintain the most
comfortable passenger compartment temperature.
The air source select switch is used to select either
ªFRESHº for the introduction of the outside air, or ªCIRCº
for the circulation of the inside air. When the switch is set
to ªFRESHº, the outside air is always taken into the
passenger compartment. When setting the switch to
ªCIRCº position, the circulation of air is restricted only to
the inside air with no introduction of the outside air and the
air in the passenger compartment gets warm quickly.
However, the switch is normally set to ªFRESHº to
prevent the windshield from clouding.

1A±4
HEATING, VENTILATION AND AIR CONDITIONING (HVAC)
840R200007
Legend
(1) Defroster Nozzle
(2) Ventilation Duct
(3) Blower Assembly(4) Evaporator Assembly
(5) Ventilation Lower Duct
(6) Heater Unit
(7) Rear Heater Duct

HEATING, VENTILATION AND AIR CONDITIONING (HVAC)
1A±5
C01RW001
Air Source Select Switch
Press this button to select either Fresh Air Intake or CIRC
(inside air circulation). There is an indicator light inside the
button. This light indicates that the CIRC mode is ªONº.
Fresh Air Intake is the default setting for both DEFROST
and FOOT/DEFROST.
Fan Control Switch
This switch controls the blower motor speed to regulate
the amount of air delivered to the defrost, foot, and
ventilation ducts:
1. L0
2. M1
3. M2
4. M3
5. HI
Temperature Control Switch
When the temperature control switch is in the ª18
C
(65
F)º position, the air mix door closes to block the air
flow to the heater core.
When the temperature control switch is in the ª32
C
(90
F)º position, the air mix door opens to allow air to pass
through the heater core and heat the passenger
compartment.
Selecting the desired temperature will control the air flow
through the heater core, allowing control of the cabin
temperature.

1A±6
HEATING, VENTILATION AND AIR CONDITIONING (HVAC)
Heater Unit
Heater Unit and Associated Parts
840R200008
Legend
(1) Instrument Panel Assembly
(2) Cross Beam Assembly
(3) Instrument Panel Bracket W/Suspension
Control Unit
(4) Ventilation Lower Duct(5) Rear Heater Duct
(6) Evaporator Assembly
(7) Heater Unit Assembly
(8) Heater Hose
(9) Power Transistor Connector
Removal
1. Disconnect the battery ground cable.
2. Drain the engine coolant.
3. Discharge and recover refrigerant (with air
conditioning).

Refer to
Refrigerant Recovery in this section.
4. Remove the Instrument panel assembly.

Refer to
Instrument Panel Assembly in Body and
Accessories section.
5. Remove instrument panel bracket w/suspension
control unit.

Refer to
Cross Beam Assembly in Body and
Accessories section.
6. Cross Beam Assembly.

Refer to
Cross Beam Assembly in Body and
Accessories section.
7. Disconnect power transistor connector.
8. Remove evaporator assembly.

Refer to
Evaporator Assembly in this section.
9. Remove ventilation lower duct.
10. Remove rear heater duct.

Remove foot rest, carpet and 3 clips.
11. Disconnect mode/mix actuator connector.
12. Remove heater unit assembly.

Disconnect heater hoses at heater unit.
Installation
To install, follow the removal steps in the reverse order,
noting the following points:
1. When handling the PCM and the control unit, be
careful not to make any improper connection of the
connectors.

HEATING, VENTILATION AND AIR CONDITIONING (HVAC)
1A±7
2. When installing the heater unit, defroster nozzle and
center vent duct, be sure that the proper seal is made,
without any gap between them.
Heater Core and / or Mode Door
Disassembled View
860R200001
Legend
(1) Heater Core
(2) Case (Temperature Control)
(3) Heater Unit
(4) Mix Actuator(5) Mode Door
(6) Duct
(7) Mode Actuator
(8) Case (Mode Control)