2004 ISUZU TF SERIES charging

1-34 HEATER AND AIR CONDITIONING


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

A fully charged system is indicated by the sight glass on
the receiver/drier being free of any bubbles (Refer to
"Reading Sight Glass").

Check the high and low pressure value of the manifold
gauge. (Refer to “CHECKING REFRIGERANT SYSTEM
WITH MAINFOLD GAUGE” in SERVICE
INFORMATION.)
Immediately after charging refrigerant, both high and low
pressures are slightly high and to the left of the gauge, but they
settle down to the guide pressure valves as shown below:
 Ambient temperature; 3035C (8695F)

Guide pressure
High-pressure side;
Approx. 1373
1670 kPa (14
17 kg/cm
2 / 199
242 PSI)
Low-pressure side;
Approx. 127
245 kPa (1.3
2.5 kg/cm
2 / 18
36 PSI)
10) Close the low pressure hand valve and charge valve of the
refrigerant container.
11) Stop the air conditioning and the engine.
12) Disconnect the high and low pressure hoses from the
manifold gauge fittings.

1-46 HEATER AND AIR CONDITIONING

GENERAL REPAIR PROCEDURE
OIL SPECIFICATION

The HFC-134a system requires a synthetic (PAG)
compressor oil.

Compressor (PAG) oil varies according to compressor
model. Be sure to use oil specified for the model of
compressor.
Specified Compressor Oil
DH-PR



HANDLING OF OIL

The oil should be free from moisture, dust, metal powder,
etc.
 Do not mix with other oil.
 The water content in the oil increases when exposed to the
air. After use, seal oil from air immediately.

The compressor oil must be stored in steel containers, not
in plastic containers.

COMPRESSOR OIL CHECK
The Oil used to lubricate the compressor is circulating with the
refrigerant.
Whenever replacing any component of the system or a large
amount of gas leakage occurs, add oil to maintain the original
amount of. oil.

Oil Capacity

Capacity total in
system CR-14 180 cm3 (5.0 fl.oz.)
Compressor
(Service parts)
charging amount
CR-14
180 cm
3 (5.0 fl.oz.)

HEATER AND AIR CONDITIONING 1-47

Checking and Adjusting for Used Compressor
(1) Perform Oil return operation.
(Refer to "Oil Return Operation" in this section.)
(2) Discharge refrigerant and remove the compressor.


(3) Drain the compressor oil and measure the extracted oil with
a measuring cylinder.
(4) Check the compressor oil for contamination.
(Refer to "Contamination of Compressor Oil" in this
section.)
(5) Adjust oil level following the procedure below.

Type Collected Amount Charging Amount
more than 90 cm3
(3.0 fl.oz.) same as collected
amount
less than 90 cm3
(3.0 fl.oz.) 90 cm3 (3.0 fl.oz.) CR-14

(6) Install the compressor, then evacuate, charge and perform
oil return operation.
(7) Check system operation.


When it is impossible to perform oil return operation, the
compressor oil should be checked in the following order:
(1) Discharge refrigerant and remove the compressor.
(2) Drain the compressor oil and measure the extracted oil with
a measuring cylinder.
(3) Check the oil for contamination.
(4) If more than 90 cm
3 (3.0 fl.oz.) for CR-14 type is extracted
from the compressor, supply same amount of oil to the
compressor to be installed.
If the amount of oil extracted is less than 90 cm
3 (3.0 fl.oz.)
for CR-14 type recheck the compressor oil in the following
order:
(5) Supply 90 cm
3 (3.0 fl.oz.) for CR-14 type oil to the
compressor and install it onto the vehicle.
(6) Perform oil return operation.
(7) Remove the compressor and recheck the amount of oil.
(8) Adjust the compressor oil.

HEATER AND AIR CONDITIONING 1-83

AIR CONDITIONING CYCLE TROUBLESHOOTING

TROUBLE POSSIBLE CAUSE CORRECTION
No cooling or
insufficient
cooling
1. Magnetic clutch does not run


Refer to “MAGNETIC CLUTCH”
troubleshooting in this section
2. Compressor is not rotating properly

Drive belt loosened or broken

Adjust the drive belt to the specified
tension or replace the drive belt


Magnetic clutch face is not clean and
slips
Clean the magnetic clutch face or replace




Incorrect clearance between magnetic
drive plate and pulley

Adjust the clearance (Refer to
“COMPRESSOR OVERHAUL”



Compressor oil leaks from shaft seal or
shell

Replace the compressor




Compressor seized

Replace the compressor

3. Insufficient or excessive charge of
refrigerant

Discharge and recover refrigerant.
Recharge to specified amount.
4. Leaks in the refrigerant system




Check refrigerant system for leaks and
repair as necessary
Discharge and recover refrigerant.
Recharge to specified amount.
5. Condenser clogged or insufficient radiation


Clean the condenser or replace as
necessary


Check radiator or condenser fan function

6. Temperature control link unit of the heater
unit defective

Repair the link unit

7. Unsteady operation due to foreign
substance in expansion valve

Replace the expansion valve

8. Poor operation of electronic thermostat


Check electronic thermostat and replace
as necessary
Insufficient
velocity
of cooling air

1. Evaporator clogged or frosted


Check evaporator core and replace or
clean the core
2. Air leaking from cooling unit or air duct

Check evaporator and duct connection,
then repair as necessary

3. Blower motor does not rotate prop-erly


Refer to “FAN CONTROL KNOB (FAN
SWITCH)” troubleshooting in this section

* For the execution of the charging and discharging operation in the table above, refer to the “RECOVERY,
RECYCLING, EVACUATING AND CHARGING” in this section.

HEATER AND AIR CONDITIONING 1-85

RESULT SYMPTOM TROUBLE CAUSE CORRECTION
Discharge
(High)
pressure
gauge
abnormally
high Reduced or no air flow through
the condenser


Condenser clogged or dirty


Radiator (condenser) fan
does not operate properly

Clean


Check cooling fan
operation
No bubbles in sight glass when
condenser is cooled by water
(Insufficient cooling)




Excessive refrigerant in
system





Check sight glass.
(See “Reading Sight
Glass”)


Discharge and
recover refrigerant.
Recharge to specified
amount
After stopping air conditioning,
pressure drops approx. 196 kPa
(2.0kg/cm
2 / 28 PSI) quickly

Air in system


Evacuate and charge
refrigerant system
Discharge
(High)
pressure
gauge
abnormally
low Insufficient cooling and excessive
bubbles in the sight glass







Insufficient refrigerant in
system







Check sight glass.
(See “Reading Sight
Glass”)

Check for leaks


Discharge and
recover refrigerant.
Recharge to specified
amount
Low pressure gauge indicates
vacuum

Clogged or defective
expansion valve

Replace the
expansion valve
Frost or dew on refrigerant line
before and after receiver/ drier or
expansion valve, and low pres-
sure gauge indicates vacuum
Restriction caused by debris
or moisture in receiver/drier


Check system for
restriction and
replace receiver/drier

After turning off air conditioning,
high and low pressure gauge
balanced quickly


Compressor seal defective


Poor compression due to
defective compressor
gasket

Replace or repair
compressor
Suction
(Low)
pressure
gauge
abnormally
high Low pressure gauge is lowered
after condenser is cooled by
water


Excessive refrigerant in
system



Discharge and
recover refrigerant
Recharge to specified
amount
Low pressure hose temperature
around the compressor refrigerant
line connector is lower than
around evaporator



Unsatisfactory valve
operation due to defective
temperature sensor of
expansion valve


Expansion valve opens too
long

Replace the
expansion valve




After turning off air conditioning,
high and low pressure gauge is
balanced quickly

Compressor gasket is
defective


Replace


Air conditioning turns off before
passenger compartment is
sufficiently
cool
Electronic thermostat
defective

Check the electronic
thermostat and
replace as necessary


* For the charging and discharging operations in the table above, refer to “RECOVERY, RECYCLING,
EVACUATION AND CHARGING” in this section.

7A2-32 TRANSMISSION CONTROL SYSTEM (AW30 –40LE) (V6 3.5L)

Clear DTC
NOTE: If you clear the DTC (Diagnostic Trouble
Codes) you will not be able to read any codes recorded
during the last occurrence.
NOTE: To use the DTC again to identify a problem,
you will need to reproduce the fault or the problem.
This may require a new test drive or just turning the
ignition on (this depends on the nature of the fault).
1. IF you have a Tech 2:
1. Connect the Tech 2 if it is still not connected go
through Tech 2 OBD CONNECTION.
2. Push “F1: Clear DTC Information" in the
Application Menu and answer “Yes" to the
question “Do you want to clear DTC's?"
a. When a malfunction still exists and the Tech 2 displays “AW30-40 CODES NOT
CLEARED". This means that the problem is
still there or that the recovery was not done.
Please go to DTC CHECK.
b. When a malfunction has been repaired and the recovery is done the Tech 2 displays
“ AW30-40LE CODES CLEARED".
2. When you have no Tech 2, the storaged trouble
codes can be cleared by shorting the terminals
No.11 and No.4 or 5 (ground) of data link connecto
r
with a lead wire for 1  6 seconds.
DTC Check
1. Diagnostic Trouble Codes (DTC) have been
identified by Tech 2.
2. You have written the list of the DTCs. The order o
f
the malfunctions has no meanings for this TCM.
Usually only one or two malfunctions should be set
for a given problem.
3. Check directly the DTCs you identified. The DTCs
are sorted by number. Refer to Diagnostic Trouble
Code (DTC) Identification in this section.
TCM Precaution
The TCM can be damaged by:
1. The electrostatic discharge
2. The short circuit of some terminals to voltage or to
ground.
Electrostatic Discharge Damage Description: 1. Electronic components used to control systems are often designed to carry very low voltage, and
are very susceptible to damage caused by
electrostatic discharge. It is possible for less than
100 volts of static electricity to cause damage to
some electronic components. By comparison, it
takes as much as 4,000 volts for a person to even
feel the zap of a static discharge.
2. There are several ways for a person to become
statically charged. The most common methods o
f
charging are by friction and induction. An example
of charging by friction is a person sliding across a
car seat, in which a charge of as much as 25,000
volts can build up. Charging by induction occurs
when a person with well insulated shoes stands
near a highly charged object and momentarily
touches ground. Charges for the same polarity are
drained off, leaving the person highly charged with
the opposite polarity. Static charges of either type
can cause damage, therefore, it is important to
use care when handling and testing electronic
components.
NOTE: To prevent possible electrostatic discharge
damage:
1. Do not touch the TCM connector pins or soldered
components on the TCM circuit board.
2. Be sure to follow the guidelines listed below i
f
servicing any of these electronic components:
3. Do not open the replacement part package until it is time to install the part.
4. Avoid touching electrical terminals of the part.
5. Before removing the part from its package, ground
the package to a known good ground on the
vehicle.
6.
Always touch a known good ground before handling
the part. This step should be repeated before
installing the part if the part has been handled
while sliding across the seat, while sitting down
from a standing position or while walking some
distance.
Information On TCM
1. The Transmission Control Module (TCM) is located
in the place of a clutch pedal and is the control
center of the electronic transmission control
system.
2. The TCM must be maintained at a temperature below 85

C (185

F) at all times. This is most
essential if the vehicle is put through a paint baking
process. The TCM will become inoperative if its
temperature exceeds 85

C (185

F). Therefore, it is
recommended that the TCM be removed or that
temporary insulation be placed around the TCM
during the time the vehicle is in a paint oven o
r
other high temperature process.
3. The TCM is designed to process the various inputs and then respond by sending the appropriate
electrical signals to control transmission upshift,
downshift, shift feel and torque converter clutch
engagement.
4. The TCM constantly interprets information from the
various sensors, and controls the systems that
affect transmission and vehicle performance. By
analyzing operational problems, the TCM is able to