ESP ISUZU TROOPER 1998 Service Repair Manual

SAE Ð Society of Automotive Engineers
Sec Ð Secondary
SFI Ð Sequential-port Fuel Injection
SI Ð System International
SIR Ð Supplemental Inflatable Restraint System
SOHC Ð Single Overhead Camshaft
Sol Ð Solenoid
SPEC Ð Specification
Speedo Ð Speedometer
SRS Ð Supplemental Restraint System
ST Ð Start
Sw Ð Switch
SWB Ð Short Wheel Base
SYN Ð Synchronize
TAC Ð Thermostatic Air Cleaner
Tach Ð Tachometer
TBI Ð Throttle Body Injection
TCC Ð Transmission/Transaxle Converter Clutch
TCM Ð Transmission/Transaxle Control Module
TDC Ð Top Dead Center
Term Ð Terminal
TEMP Ð Temperature
TPS Ð Throttle Position Sensor
TRANS Ð Transmission/Transaxle
TURBO Ð Turbocharger
TV Ð Throttle Valve
TVRS Ð Television & Radio Suppression
TVS Ð Thermal Vacuum Switch
3 A/T Ð Three Speed Automatic Transmission/
Transaxle
2WD Ð Two Wheel Drive
4x2 Ð Two wheel Drive
U-joint Ð Universal Joint
V Ð Volt(s)
VAC Ð Vacuum
VIN Ð Vehicle Identification Number
VRRRE Ð Vehicle Refrigerant Recovery and Recycling
Equipment
V-ref Ð ECM Reference Voltage
VRV Ð Vacuum Reducer Valve
VSS Ð Vehicle Speed Sensor
VSV Ð Vacuum Switching Valve
V-6 Ð Six Cylinder ÒVÓ Engine
V-8 Ð Eight Cylinder ÒVÓ Engine
W Ð Watt(s)
w/ Ð With
w/b Ð Wheel Base
w/o Ð Without
WOT Ð Wide Open ThrottleL Ð Liter
lbáft Ð Foot Pounds
lbáin Ð Inch Pounds
LF Ð Left Front
LH Ð Left Hand
LR Ð Left 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
MAT Ð Manifold Air Temperature
MEM-CAL Ð Memory and Calibration Unit
Max Ð Maximum
M/C Ð Mixture Control
Min Ð Minimum
mm Ð Millimeter
MPFI Ð Multi-Port Fuel Injection
MPG Ð Miles per Gallon
MPH Ð Miles per Hour
M/T Ð Manual Transmission/Transaxle
MV Ð Millivolt
NA Ð Natural Aspirated
NC Ð Normally Closed
Nám Ð Newton Meters
NO Ð Normally Open
NOx Ð Nitrogen, Oxides of
OD Ð Outside Diameter
O/D Ð Over Drive
OHC Ð Overhead Camshaft
OL Ð Open Loop
O
2Ð Oxygen
PAIR Ð Pulse Air Injection Reactor System
P/B Ð Power Brakes
PCV Ð Positive Crankcase Ventilation
PFI Ð Port Fuel Injection
PRESS Ð Pressure
PROM Ð Programmable Read Only Memory
P/N Ð Park/Neutral
P/S Ð Power Steering
PSI Ð Pounds per Square Inch
Pt. Ð Pint
Pri Ð Primary
PWM Ð Pulse Width Modulated
Qt Ð Quart
REF Ð Reference
RF Ð Right Front
RFI Ð Radio Frequency Interference
RH Ð Right Hand
RPM Ð Revolutions per Minute
RPO Ð Regular Production Option
RR Ð Right Rear
RS Ð Right Side
RTV Ð Room Temperature Vulcanizing
RVB Ð Rear Vacuum Brake
RVR Ð Response Vacuum Reducer
RWAL Ð Rear Wheel Antilock Brake
RWD - Rear Wheel Drive
GENERAL INFORMATION 0AÐ13

1BÐ74 AIR CONDITIONING
FUNCTIONS AND FEATURES
¥ Automatic interior temperature control
This function enables to maintain the interior temperature at the level specified from the temperature
control switch despite of changes in factors such as vehicle speeds, outside air temperature and number
of passengers.
¥ Maximum cooling and heating function
You can select FC (Full cool, namely maximum cooling temperature) or FH (Full heat, maximum heating
temperature) from the temperature control lever.
¥ Automatic air flow control
Air flow is automatically and consecutively fine tuned according to the specified interior temperature and
changes in aperture of the heater unit mix door.
¥ Mode (blow port) control
This function automatically selects either one of the VENT, BI-LEVEL, FOOT or DEP mode for the blow
port according to changes of temperature on the blow port. Using the mode switch allows you to select a
desired blow port manually.
¥ Intake (switching between the fresh air intake and circulation of interior air) control
The intake (switching between fresh air intake and circulation of interior air) mode automatically selects
either FRESH (fresh air intake), MIX or RECIRC (interior air circulation) according to changes of the blow
port temperature. Using the intake switch allows you to select a desired intake port manually (in the
manual operation, FRESH and RECIRC modes alone are available). Pressing the DEF (defrost) mode
switch selects the FRESH (fresh air intake).
¥ Cooler start-up timing control
This function is used for maintaining the air flow at "LOW" level until the evaporator is sufficiently cooled
down. It is intended to prevent a large volume of hot air being blowing into inside of a vehicle when the
cooler is turned on in hot summer season.
¥ Heater start-up timing control
This function is used for maintained the air flow at "LOW" level and also for maintaining the defrost
mode until temperature of coolant in the heater core is sufficiently heated. It is intended to prevent a
large volume of cool air being blown into inside of a vehicle when the heater is turned on in cold winter
season.
¥ Solar radiation quantity offset control
The photodiode on the solar radiation sensor determines solar radiation quantity accurately to offset
interior temperature quickly.
¥ Switch position storing function
This function is used for storing switch positions being selected in the immediately preceding operation,
namely the last time the ignition has been turned off. It simplifies the setup procedures when restarting
the system.
¥ Self-diagnosis function
The self-diagnosis function turned on from the panel switch makes your troubleshooting easier (for detail
of this function, refer to the section titled "Self-Diagnosis").

1BÐ82 AIR CONDITIONING
OPERATION AND FUNCTIONS OF CONTROL PANEL SWITCHES
1. Auto Switch
(1) Pressing this switch turns on the automatic control mode. It resets all manual switches except that
for the fan control. However, when the Manual REC is selected for the intake or the Manual Open is
selected for the C/V, these modes are maintained.
(2) It causes the A/C (air conditioner) to the ON mode (this function, however, available only when the
fan is turned on and also the compressor is turned on because of the given outside air temperature
level).

¥ The AUTO LED comes on.
¥ Currently selected mode for the Mode and Intake are respectively indicated.
2. Mode Switch

(1) Pressing the VENT, B/L or FOOT switch selects the corresponding mode.
(2) When the Auto is selected for the Mode and Intake, pressing the mode switch fixes the Intake to the
immediately preceding status.

¥ Turns off the Auto LED.
¥ Currently selected blow port is indicated.
3. DEF Switch
Press this switch to select the DEF mode.

*1: When the manual REC is selected for the Intake, the manual REC is maintained.
*2: The ON mode is enabled only when the fun is turned on, and also the compressor is turned on
because of the given outside air temperature level.

¥ The Auto LED is turned off.
¥ DEF is indicated for the blow port, A/C LED comes on (only when the fan is turned on), and status
display is provided for the Intake.
Example 1:
4. Intake Switch
Pressing this switch sequentially selects a different intake port in the following order.
Example 1:
Example 2:PUSH
Auto RECFRESHRECPUSHPUSH
PUSHPUSHPUSHAuto REC
MIXRECFRESH
DEF SW:ON
(Selects the DEF
mode)A/C OFF
modeA/C ON
modeA/C ON mode is
maintained.
Mode switches for other than
the DEF mode: ON
(Resets the DEF mode)
Blow port Intake port A/C MIX
DEF Auto FRESH *1 ON mode *2 Auto

AIR CONDITIONING 1BÐ89
2. Air Flow Control
¥ In the Auto Mode
The automatic heater/air conditioner control unit
operates on the setup temperature signal and
other sensor signals to derive the total signal.
Then, the control unit adjusts base potential of
the power transistor to match it to the voltage
pattern of the target fan so that stage-less fan
speed control can be achieved.
When solar radiation quantity is detected in the
VENT or B/L mode, the control unit increases the
minimum fan voltage to offset.
When FH or FC is selected from the temperature
control switch, air flow is accordingly fixed to
MAX HI or AUTO HI.
¥ In the Manual Mode
Air flow specified from the fan switch is entered
to the automatic heater/air conditioner control
unit as the manual signal. The signal modifies
the air flow to the level specified from the fan
switch so that the required fan voltage is
attained.3. Mode (Blow Port) Control
The automatic heater/air conditioner control unit
operates on the setup temperature from the
control switch, and temperature and solar
radiation quantify from the sensors to determine
the total mode control signal. According to the
pattern specified by this signal, the control unit
selects either one of the VENT, BI-LEVEL, FOOT
or DEF/FOOT mode.
The mode actuator determines the rotation
direction comparing the target position against
the current position being determined by the
position detection signal.
When FH or FC is selected for the temperature
from the temperature control switch, mode is
accordingly fixed to the VENT or FOOT.
¥ In the manual operation of the mode switch, you
can select a desired blow port mode pressing
the corresponding mode switch.
¥ Operating the DEF mode switch selects the DEF
for the blow port mode.
4.512
(V)
M
MAX
HI Relay
Power
transistor
4.8 10.5MAX HI Set up
temperature signal
Control unit
In car sensor
Ambient sensor
Sun sensor
Mode control
signal Fan switch
AUTO HI
Heater
sideCooler
side Total signalVENT mode
Blower fan motor terminal voltage
C01RY00008
Mode control
DEF / FOOTSet up temperature
signal
Mode actuator
Mode doorPosition
detection
switch
Control unit
In car sensor
Sun sensor
Air conditioning
switch
Mode control
signal Ambient sensor
FOOT
BI-LEVEL
VENT
Heater
sideCooler
side Mode total signal
C01RY00009

AIR CONDITIONING 1BÐ95
Performance and Movement checklist for Automatic Air Conditioner Related Parts
Start the engine, and when the engine coolant reached 60¡C check performance and movement of the
related parts according the following checklist.
1. Performance Check Using the Manual Switch
Checking ApproachNo.ItemAcceptance criteria
Condition Operation
Blowing
temperature
(check movement
of air mix door)
Airflow volume
(check movement
of the mode door)Set temperature to
25.0¡C.(1) Turn the fan knob
off.
(2) Turn the fan knob
from LOW to HI.(1) The fan shall be stopped, thus
stopping air blow, too.
(2) Airflow volume shall change
from LOW to HI.
Blowing
temperature
(check movement
of the mode door)Set temperature to
25.0¡C.
Set the fan knob to HI.Press the mode switch
to change the blow port
mode sequentially from
the VENT through BI-
LEVEL, FOOT up to
DEF.LED corresponding to each mode
shall be turned on and the blow
port mode shall be switched
smoothly.
The
interior/outside air
switching mode
(check movement
of intake door)Set temperature to
25.0¡C.Turn the LED off using
the interior/outside air
switch (this introduces
the outside air intake
mode). Then, the set
fan knob to HI and
press the
interior/outside switch
to turn on the LED.The LED indication shall be
switched from OFF to ON
accompanying a change in air
blowing sound.
Compressor Set the temperature to
FC. (Outside air
temperature is 0C or
above and interior
temperature at ordinary
temperature.)Press the "OFF" switch.
(1) Press the Auto
switch.
(2) Press the Air
Conditioner switch.(1) As the fan knob is set to the
Auto position, the A/C switch
LED shall come on and the
compressor shall be turned on.
(2) As the A/C LED comes off, the
compressor shall be turned off. Auto switch must be
turned on
(FAN-AUTO
MODE-AUTO)(1) Select FC for the
setup temperature.
(2) Select FH for the
setup temperature.
®Then, select the
MAX Control.(1) Cold air shall be blown out.
(2) Hot air shall be blown out.
1
2
3
4
5

1BÐ98 AIR CONDITIONING
*1. Displaying the Current Trouble Diagnosing Table
Start the engine while holding down both the Auto switch and the DEF switch on the control panel, and
the table will appear in approximately 10 seconds to the indicator lamp (LED) of the air conditioning
switch. Result of the diagnosis along the following 9 items will be shown one by one in 0.5 second
interval irrespective of presence or absence of a trouble for a given item. When the display 9 items is
completed, it is repeated with 3 seconds of interval in between. A failed item is indicated by flashing of
the LED that is repeated 3 times within 0.5 seconds. If a trouble is indicated, you can locate the failed
section by knowing when in the total sequence it has been displayed.
Items for Current Trouble Diagnosis
As shown above, display of result along nine items is repeated with 3-second interval in between.
Note 1: When checking the solar radiation sensor, apply sufficient light using a 60W bulb.
Otherwise, it can be diagnosed as failed.
Note 2: If the temperature setting lever is set on both ends (one set to 18¡C, blue scale = Full cool and
the other to 31¡C, red scale = Full hot), they can be diagnosed as failed.
Note 3: Likewise, the fan switch can be diagnosed as failed if set on both ends.
LED on
LED off Indication for presence
of a troubleIndication for normal state
0.5 0.5 0.5
3 seconds interval
ON
OFF
Display pattern Failed part
Normal pattern
In car sensor
Ambient sensor
Sun sensor (Note 1)
Duct sensor
Temperature control lever (Note 2)
Fan switch (Note 3)
Mix actuator
Mode (blow port) control
Intake (fresh air/interior air switching) control
F01RX010
F01RY00008

AIR CONDITIONING 1BÐ99
*2. Displaying the Past Trouble Diagnosing Table
The past trouble diagnosis displays only the items on which trouble has recurred 16 times in the past.
If you press the air conditioning switch once while the current trouble diagnosis is taking place, display
of the past trouble diagnosis will appear on the indicator lamp (LED) of the air conditioning switch.
Results of the diagnosis along the following five items are displayed one by one in 0.5 second interval
irrespective of presence or absence of a trouble. A failed item is indicated by flashing of the LED that is
repeated 3 times within 0.5 seconds. You can locate the failed section by counting in what sequence it
has been displayed.
Items for Past Trouble Diagnosis
LED on
LED off Indication for presence of a trouble Indication for normal state
0.5 0.5 0.5
3 second interval
Display pattern
ON
OFFNormal pattern
In car sensor
Ambient sensor
Sun sensor
Duct sensor
Mix actuatorFailed part
F01RX011
F01RY00007
*3. Check of Output Equipment
FAN
MIX
MODE
DOOR
INTAKE
DOOR
SET UP
TEMPERATURE
100
(%)
33.5
F/H
VENT
B/L
FOOT
D/F
DEF
REC
MIX
FRE
F/C 20 21 22 23 24 25 26 27 28 29 30 F/H (%)
F/C
F01RY00001

AIR CONDITIONING 1BÐ123
Inspection of the Air Conditioner Room Temperature Setup System
¥ Conflicts Between the Set Temperature and Actual Room Temperature
NOReplace the failed sensor.
NO
NO
Failure on the automatic heater/air
conditioner control unit.
YES YESYES
Is the in car sensor intaking the room
air? (Refer to the later section on "Check
Up".)
Is the air mix link properly attached?
(Make sure that selecting FH or FC using
the lever respectively sets the mix door
to the full hot or full cool.)
Are the interior temperature sensor and
the outside air temperature sensor
functioning normally?
Failure on the in car sensor.
Failure on the air mix link or the actuator.

AIR CONDITIONING 1BÐ125
Power Transistor
1. Remove the power transistor connector (I-47)
from the evaporator assembly.
2. Check the conduction between the power
transistor side terminals.
MAX HI Relay
1. Remove the MAX HI relay connector (B-64) from
the blower assembly.
2. Check the conduction between the MAX HI relay
side terminals.In Car Sensor
1. Turn on the ignition switch (the engine is
started). Start the air conditioner in "Full Auto".
2. Make sure that the in car sensor suctions
cigarette smokes and such.
3. Dismount the in car sensor from the automatic
heater/air conditioner control unit. Connect (+)
end and (-) end of the battery to the aspirator
motor side terminals No.1 and No.2
, respectively, then
check if the motor runs normally.I-34
I-34














"650
4321
C01RW020
43
3 41
2 21
No continuity between terminals (2) and (4).
Continuity between terminal (2) and (4) when battery
voltage is applied between (1) and (3).
C01RY00003
1
2
3
Terminal
No.Conduction
Conducted (50½ maximum)
Conducted (100½ maximum)
Conducted (220½ maximum) Not conducted
Not conducted 1
µ23
Testing
rod
µ
µ
µ
µ
´
´
´
´
´
1 23
C01RY00002

COMPRESSOR OVERHAUL 1D Ð 25
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.
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 "ON"
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.
Compressor Leak Testing (External and
Internal)
Bench-Check Procedure
1. Install test plate J-39893 on rear head of compressor.
2. Using Refrigerant Recovery System, attach center
hose of manifold gage set on charging station to a
refrigerant drum standing in an upright drum.
3. Connect charging station high and low pressure
lines to corresponding fittings on test plate J-39893.
Suction port (low-side) of compressor has large
internal opening. Discharge port (high-side) has
smaller internal opening into compressor and
deeper recess.
4. Open low pressure control, high pressure control
and refrigerant control on charging station to allow
refrigerant vapor to flow into compressor.
5. Using a leak detector, check for leaks at pressure
relief valve, rear head switch location, compressor
front and rear head seals, center cylinder seal,
through bolt head gaskets and compressor shaft
seal. After checking, shut off low pressure control
and high-pressure control on charging station.
6. If an external leak is present, perform the necessary
corrective measures and recheck for leaks to make
certain the leak has been connected.
7. Recover the refrigerant.
8. Disconnect both hoses from the test plate J-39893.
9. Add 90 ml (3 oz.) new PAG lubricant to the
compressor assembly. Rotate the complete
compressor assembly (not the crankshaft or drive
plate hub) slowly several turns to distribute oil to all
cylinder and piston areas.
10. Install a M9 ´1.25 threaded nut on the compressor
crankshaft if the drive plate and clutch assembly are
not installed.
11. Using a box-end wrench or socket and handle,
rotate the compressor crankshaft or clutch drive
plate on the crankshaft several turns to insure
piston assembly to cylinder wall lubrication.
12. Using Refrigerant Recovery System, connect the
charging station high-pressure line to the test plate
J-39893 high-side connector.
13. Using Refrigerant Recovery System, connect the
charging station low-pressure line to the low
pressure port of the test plate J-39893. Oil will drain
out of the compressor suction port if the compressor
is positioned with the suction port downward. (Component parts to be (Amount of Oil)
installed)
Evaporator 50 cc (1.7 fl. oz.)
Condenser 30 cc (1.0 fl. oz.)
Receiver/dryer 30 cc (1.0 fl. oz.)
Refrigerant line (one 10 cc (0.3 fl. oz.)
piece)
(Amount of oil drained (Charging amount of oil
from used compressor) to new compressor)
more than 90 cc same as drained amount
(3.0 fl.oz)
less than 90 cc (3.0 fl.oz) 90 cc (3.0 fl.oz)