engine ISUZU AXIOM 2002 Service Owner's Manual

HEATING, VENTILATION AND AIR CONDITIONING (HVAC)
1A±31
Air Conditioning System
Individual Inspection
Triple Pressure Switch (V6, A/T)
1. Disconnect the connector and check for continuity
between pressure switch side connector terminals (1)
and (2).
2. Reconnect the connector to activate the A/C switch,
and check to see if there is continuity between the
chassis side connector terminals (3) and (4) and the
fan operates.
875RY00010
Condenser Fan
1. Disconnect the condenser fan connector.
2. Connect the battery positive terminal to the
condenser fan side connector terminal No.C-16-1
and negative to the No.C-16-2.
3. Check that condenser fan is rotating correctly.
875R200002
General Repair Procedure
Precautions For Replacement or Repair of
Air Conditioning Parts
There are certain procedures, practices and precautions
that should be followed when servicing air conditioning
systems:

Keep your work area clean.

Always wear safety goggles and protective gloves
when working on refrigerant systems.

Beware of the danger of carbon monoxide fumes
caused by running the engine.

Beware of discharged refrigerant in enclosed or
improperly ventilated garages.

Always disconnect the negative battery cable and
discharge and recover the refrigerant whenever
repairing the air conditioning system.

When discharging and recovering the refrigerant, do
not allow refrigerant to discharge too fast; it will draw
compressor oil out of the system.

Keep moisture and contaminants out of the system.
When disconnecting or removing any lines or parts,
use plugs or caps to close the fittings immediately.
Never remove the caps or plugs until the lines or parts
are reconnected or installed.

When disconnecting or reconnecting the lines, use
two wrenches to support the line fitting, to prevent
from twisting or other damage.

Always install new O-rings whenever a connection is
disassembled.

Before connecting any hoses or lines, apply new
specified compressor oil to the O-rings.

When removing and replacing any parts which
require discharging the refrigerant circuit, the
operations described in this section must be
performed in the following sequence:
1. Use the J-39500 (ACR
4: HFC-134a Refrigerant
Recovery / Recycling / Recharging / System) or
equivalent to thoroughly discharge and recover the
refrigerant.
2. Remove and replace the defective part.
3. After evacuation, charge the air conditioning
system and check for leaks.

1A±36
HEATING, VENTILATION AND AIR CONDITIONING (HVAC)
3. Connect the low pressure charging hose of the
manifold gauge to the low pressure side service valve
of the vehicle.
4. Connect the high pressure charging hose of the
manifold gauge to the high pressure side service
valve of the vehicle.
901R100021
Legend
(1) Low Side
(2) High Side
(3) Refrigerant Container
(4) Weight Scale
5. Place the refrigerant container(3) up right on a weight
scale(4).
Note the total weight before charging the refrigerant.
a. Open the refrigerant container valve.
b. Open the low side vale on the manifold gauge set.
Refer to the manufacturer's instructions for a
weight scale charging station.
901RS144
6. Perform a system leak test:

Charge the system with approximately 200 g
(0.44 lbs) of HFC-134a.

Make sure the high pressure valve of the manifold
gauge is closed.

Check to ensure that the degree of pressure does
not change.

Check for refrigerant leaks by using a HFC-134a
leak detector.

If a leak occurs, recover the refrigerant. Repair the
leak and start all over again from the first step of
evacuation.
7. If no leaks are found, continue charging refrigerant to
the air conditioning system.

Charge the refrigerant until the scale reading
decreases by the amount of the charge specified.
Specified amount: 700 g (1.54 lbs)

If charging the system becomes difficult:
1. Run the engine at idle and close all the vehicle
doors.
2. Turn A/C switch ªONº.
3. Set the fan switch to its highest position.
4. Set the air source selector lever to ªCIRCº.
5. Slowly open the low side valve on the manifold
gauge set.
WARNING: BE ABSOLUTELY SURE NOT TO OPEN
THE HIGH PRESSURE VALVE OF THE MANIFOLD
GAUGE. SHOULD THE HIGH PRESSURE VALVE BE
OPENED, THE HIGH PRESSURE REFRIGERANT
WOULD FLOW BACKWARD, AND THIS MAY CAUSE
THE REFRIGERANT CONTAINER TO BURST.

HEATING, VENTILATION AND AIR CONDITIONING (HVAC)
1A±37
8. When finished with the refrigerant charging, close the
low pressure valve of the manifold gauge and
container valve.
9. Check for refrigerant leaks.
Checking The A/C System
1. Run the engine and close all the vehicle doors.
2. Turn A/C switch ªONº, set the fan switch to its highest
position.
3. Set the air source switch to ªCIRCº, set the
temperature switch to the full cool position.
4. Check the high and low pressure of the manifold
gauge.

Immediately after charging refrigerant, both high
and low pressures might be slightly high, but they
settle down to the pressure guidelines shown
below:

The ambient temperature should be between
25±30
C (77±86
F).

The pressure guideline for the high-pressure side is
approximately 1372.9±1863.3 kPa (199.1±270.2
psi).

The pressure guideline for the low-pressure side is
approximately 147.1±294.2 kPa (21.3±42.7 psi).

If an abnormal pressure is found, refer to
Checking
The Refrigerant System With Manifold Gauge in
this section.
5. Put your hand in front of the air outlet and move the
temperature switch of the control panel to different
positions. Check if the outlet temperature changes as
selected by the control switch.

1A±40
HEATING, VENTILATION AND AIR CONDITIONING (HVAC)
Condenser Assembly
Condenser Assembly and Associated Parts
875R200022
Legend
(1) Refrigerant Line
(2) Pressure Switch Connector
(3) Condenser & Receiver Tank Assembly
(4) Condenser Air Guide
(5) Front Bumper Assembly(6) Engine Hood Front End W/Engine Hood Lock
& Bumper Stay
(7) Front Center Bumper Retainer
(8) Front Side Bumper Retainer (RH)
(9) Head Light (R/LH)
(10) Front Side Turn Signal Light (R/LH)
(11) Horn (R/LH)
Removal
1. Disconnect the battery ground cable.
2. Discharge and recover refrigerant.

Refer to
Refrigerant Recovery in this section.
3. Remove front bumper assembly.

Refer to the
Front Bumper in Body Structure
section.
4. Remove front center bumper retainer.
5. Remove front side bumper retainer (RH).
6. Remove condenser air guide.
7. Remove engine hood front end with engine hood lock
& bumper stay.

Apply setting mark to the engine hood lock fixing
position before removing it.

HEATING, VENTILATION AND AIR CONDITIONING (HVAC)
1A±41
8. Remove horn (R/LH).
9. Remove front side turn signal light (R/LH).
10. Remove head light (R/LH).
11. Disconnect pressure switch, ambient sensor and
condenser fan connector.
12. Disconnect refrigerant line.

When removing the line connector, the connecting
part should immediately be plugged or capped to
prevent foreign matter from being mixed into the
line.
13. Remove condenser & receiver tank assembly.

Handle with care to prevent damaging the
condenser or radiator fin.
Installation
1. Install condenser & reciver tank assembly.

If installing a new condenser, be sure to add 30cc
(1.0 fl. oz.) of new compressor oil to a new one.

Tighten the condenser fixing bolts to the specified
torque.
Torque: 6 Nwm (52 lb in)
2. Connect refrigerant line.

Tighten the inlet line connector fixing bolt to the
specified torque.
Torque: 15 Nwm (11 lb ft)

Tighten the outlet line connector fixing bolt to the
specified torque.
Torque: 6 Nwm (52 lb in)

O-rings cannot be reused. Always replace with new
ones.

Be sure to apply new compressor oil to the O-rings
when connecting the refrigerant line.
3. Connect pressure switch, ambient sensor and
condenser fan connector.
4. Install head light (R/LH).
5. Install front side turn signal light (R/LH).
6. Install horn (R/LH).
7. Install engine hood front end with engine hood lock &
bumper stay.

Align the setting mark when installing.
8. Install condenser air guide.
9. Install front side bumper retainer (RH).
10. Install front center bumper retainer.
11. Install front bumper assembly.

1A±60
HEATING, VENTILATION AND AIR CONDITIONING (HVAC)
Checking and Adjusting for
Compressor Replacement
150 cc (5.0 fl.oz.) of oil is charged in compressor (service
parts). So it is necessary to drain the proper amount of oil
from the new compressor.
1. Perform oil return operation.
2. Discharge and recover the refrigerant and remove the
compressor.
3. Drain the compressor oil and measure the extracted
oil.
4. Check the compressor oil for contamination.
5. Adjust the oil level as required.
(Amount of oil drained
from used compressor)
(Draining amount of oil
from new compressor)
less than 90 cc (3.0 fl.oz)Same as drained
amount
more than 90 cc (3.0
fl.oz)90 cc (3.0 fl.oz)
6. Evacuate, charge and perform the oil return
operation.
7. Check the system operation.
Contamination of Compressor Oil
Unlike engine oil, no cleaning agent is added to the
compressor oil. Even if the compressor runs for a long
period of time (approximately one season), the oil never
becomes contaminated as long as there is nothing wrong
with the compressor or its method of use.
Inspect the extracted oil for any of the following
conditions:

The capacity of the oil has increased.

The oil has changed to red.

Foreign substances, metal powder, etc., are present
in the oil.
If any of these conditions exists, the compressor oil
is contaminated. Whenever contaminated
compressor oil is discovered, the receiver/drier must
be replaced.
Oil Return Operation
There is close affinity between the oil and the refrigerant.
During normal operation, part of the oil recirculates with
the refrigerant in the system. When checking the amount
of oil in the system, or replacing any component of the
system, the compressor must be run in advance for oil
return operation. The procedure is as follows:
1. Open all the doors and the engine hood.
2. Start the engine and air conditioning switch to ªONº
and set the fan control knob at its highest position.
3. Run the compressor for more than 20 minutes
between 800 and 1,000 rpm in order to operate the
system.
4. Stop the engine.
Replacement of Component Parts
When replacing the system component parts, supply the
following amount of oil to the component parts to be
installed.
(Component parts to be
installed)
(Amount of Oil)
Evaporator 50 cc (1.7 fl. oz.)
Condenser30 cc (1.0 fl. oz.)
Receiver/dryer30 cc (1.0 fl. oz.)
Refrigerant line (one
piece)10 cc (0.3 fl. oz.)

HEATING, VENTILATION AND AIR CONDITIONING (HVAC)
1A±85
Compressor Control
In the automatic control mode, the automatic air
conditioner control unit turns on or off the compressor
with the evaporator anti-freeze mechanism using the
evaporation sensor. And, when outside air is detected to
be low through the outside air temperature sensor signal,
the control unit turns off the compressor using the
compressor control function.
Manual Control

In the automatic control mode, pressing the A/C (air
conditioning) switch turns off the compressor.

Pressing the DEF mode switch automatically turns on
the compressor.
C01R200002
Heater Start-up Control
Heater start-up control occurs when the air discharge
mode is in the BI=LEVEL, FOOT, or DEF/FOOT position
and the heater core temperature is less than 14
C (58
F).
Air discharge volume remains in the AUTO LO mode until
the engine coolant temperature rises above 14
C (58
F).
The volume then increases in linear increments to the
pre-set level.
840R200010
Cooler Start-up Control
When cooler operation is started with the air discharge
mode is in the VENT or B/L position and the in-car
temperature higher than 26
C (78
F) (detected by the
in-car sensor), cooler start-up control occurs.
For the first 7 seconds of cooler operation, the fan
remains OFF. It then switches to AUTO LO. Air discharge
volume then increases in linear increments to the pre-set
level.
Cooler start-up control occurs the first time the engine is
started or the cooler switch is moved from OFF to AUTO.
It will not occur during subsequent switch movements.
C06R200001

HEATING, VENTILATION AND AIR CONDITIONING (HVAC)
1A±89
Performance and Movement
checklist for Automatic Air
Conditioner Related Parts
Start the engine, and when the engine coolant reached
50
C (122
F) check performance and movement of the
related parts according the following checklist.
Performance Check Using the Manual Switch
NoItemProcedureCriteriaNo.ItemConditionOperationCriteria
1
Air discharge
temperature
(Ai i d
Auto±switch ONSet temperature to
18
C (65
F).Cold air discharge.
1(Air±mix door
operation)Set temperature to
32
C (90
F).Hot air discharge.
2
Air discharge
volume (Fan
operation)Fan switch ON1. Set temperature to
25
C (77
F).
2. Press the OFF
switch.Fan does not operate. There is no
air discharge.
21. Set temperature to
25
C (77
F).
2. Press the fan 
switch.Fan operates. Fan speed increases
each time the switch is pressed (LO
to HI in 5 increments).
3
Air discharge
temperature
(Mode door
operation)Fan in manual
5±speed operation1. Set temperature to
25
C (77
F).
2. Press the mode
switch.
3. Move through the 5
modes
(VENT"BI±LEVEL
"FOOT"DEF/FO
OT"DEF).
Panel display lights for each
mode.

Air discharge outlet position
changes for each mode.
4
Inside/outside air
mode (Intake door
operation)Auto±switch ON1. Set temperature to
25
C (77
F).
2. Press the intake
switch.
3. Press the fan 
switch.
4. Set the fan to the
highest speed.
5. Press the intake
switch.
Intake switch LED turns from on
to off.

Air discharge sound changes.
5
CompressorOutside air
temperature above
0
C (32
F) and
vehicle interior at
normal temperature1. Set temperature to
25
C (77
F).
2. Press the OFF
switch.
3. Press the
auto±switch.
4. Press the air
conditioner switch.
When the auto±switch is
pressed, the LED in the air
conditioner switch turns on and
the compressor begins
operation.

When the air conditioner switch
is pressed, the LED in the air
conditioner switch turns off and
the compressor stops operation.

1A±92
HEATING, VENTILATION AND AIR CONDITIONING (HVAC)
StepActionValue(s)Ye sNo
11. Allow the engine to idle until it completely warms up.
2. Turn the starter switch to the OFF position.
3. Place a 60±watt lamp approximately 15 cm from the
sun sensor.
NOTE: This procedure is best performed at night or in
a dark, unlit area.
Is the action complete?
ÐGo to Step 2Ð
2Simultaneously press and hold the RESET key and the
CLOCK key (display unit).
Move the starter switch to start the engine.
Does DIAG appear on the display?
ÐGo to Step 3
Replace
display unit
3Press the COMPUTER MODE key.
Does DIAG AIRCON appear on the display?
ÐGo to Step 4
Replace
audio unit
4NOTE: A '1' should appear in the set temperature
segment of the display.
Does '0' appear in the outside air segment of the
display?
ÐGo to Step 6Go to Step 5
5Repair or replace damaged parts.
NOTE: Refer to
Step 1 Trouble Code Table.
Is the action complete?ÐGo to Step 1Ð
6Press and release the  fan switch (one time only).
NOTE: A '2' should appear in the set temperature
segment of the display.
Does '0' appear in the outside air segment of the
display?
ÐGo to Step 8Go to Step 7
7Repair or replace damaged parts.
NOTE: Refer to
Step 2 Trouble Code Table.
Is the action complete?ÐGo to Step 1Ð
8Press and release the  fan switch (one time only).
NOTE:

Refer to
Step 3 Sensor Output Check for a sample
output value.

A '3' should appear in the set temperature
segment of the display.
Does the correct sensor output value appear in the
outside air segment of the display?
ÐGo to Step 10Go to Step 9
9Repair or replace damaged parts.
NOTE: Refer to
Trouble Spot Inspection.
Is the action complete?ÐGo to Step 1Ð
10Press and release the  fan switch one time only.
NOTE: Refer to
Step 4 (Operation Check) for display
readings and inspection steps.
Are all parts operating normally?
ÐGo to Step 12Go to Step 11

1A±102
HEATING, VENTILATION AND AIR CONDITIONING (HVAC)
ConditionPossible causeCorrection
Does not work at allÐRefer to Chart A
Control failureÐRefer to Chart B
Chart A: Does Not Work At All
StepActionValue(s)Ye sNo
1Is the fuse FL±1 normal?
ÐGo to Step 2
Replace the
fuse
2Is the fuse F±7 normal?
ÐGo to Step 3
Replace the
fuse
3Is the relay X±1 normal?
ÐGo to Step 4
Replace the
relay
4Turn on the ignition switch. (the engine is run.)
Is the battery voltage applied between the harness side
connector terminal No.C33±3 and ground?
Approx 12VGo to Step 6Go to Step 5
5Repair an open circuit between terminal No.C33±3 and
No.X1±1.
Is the action complete?
ÐGo to Step 4Ð
6Is the battery voltage applied between the harness side
connector terminal No.C33±4 and ground?
Approx 12VGo to Step 8Go to Step 7
7Replace the intake actuator motor.
Is the action complete?
ÐGo to Step 6Ð
8Is there continuity between the harness side connector
terminal No.I19±11 and No.C33±4?
ÐGo to Step 10Go to Step 9
9Repair an open circuit between No.I19±11 and C33±4.
Is the action complete?
ÐVerify repairÐ
10Replace the auto air conditioner control unit.
Is the action complete?
ÐVerify repairÐ