Page 86 of 6020

1-52 HEATER AND AIR CONDITIONING
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
(2.53 lmp fl oz) same as collected
amount
less than 90 cm3
(2.53 lmp fl oz) 90 cm3
(2.53 lmp 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 (2.53 lmp 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 (2.53 lmp
fl oz) for CR-14 type recheck the compressor oil in the
following order:
(5) Supply 90 cm
3 (2.53 lmp 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.
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Page 87 of 6020

HEATER AND AIR CONDITIONING 1-53
Checking and Adjusting for Compressor
Replacement
180 cm3 (5.07 lmp 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 refrigerant and remove the compressor.
3) Drain the compressor oil and measure the extracted oil.
4) Check the compressor oil for contamination.
5) Adjust oil level as required.
Amount of oil drained
From used compressor Draining amount of oil
From new compressor
less than
90 cm
3 (2.53 lmp fl oz) Some as drained
amount
more than
90 cm
3 (2.53 lmp fl oz) 90 cm
3 (2.53 lmp fl oz)
6) Evacuate, charge and perform oil return operation.
7) Check system operation.
CONTAMINATION OF COMPRESSOR OIL
Unlike engine oil, no cleaning agent is added to the
compressor oil. Even is the compressor runs for a long period
of time (approximately 1 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 color to red.
• Foreign substances, metal powder, etc., are present in the
oil.
If any of these conditions exists, compressor oil is
contaminated. Whenever contaminated compressor oil is
discovered, the receiver/drier must be replaced.
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Page 88 of 6020

1-54 HEATER AND AIR CONDITIONING
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.
W hen 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 the all doors and engine hood.
2) Start the engine and A/C switch is "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
W hen replacing 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 cm3 (1.41 lmp fl oz)
Condenser 30 cm3 (0.84 lmp fl oz)
Receiver/drier 30 cm3 (0.84 lmp fl oz)
Refrigerant line (One piece) 10 cm3 (0.28 lmp fl oz)
Refrigeration oil must be replenished if more than two parts
are removed at the same time. After installing these
components, check compressor oil.
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Page 89 of 6020
HEATER AND AIR CONDITIONING 1-55
DISASSEMBLY
This illustration is based on the 4J engine model
RTW 510MF000301
Disassembly Steps
1. Drive plate bolt
2. Plain washer
3. Drive plate
4. Snap ring
5. Pulley assembly
6. Snap ring
7. Field coil
8. Compressor
Important Operations - Disassembly
RTW 510SH000701
1. Drive Plate Bolt
Using drive plate holder to prevent the drive plate from rotating, then remove the bolt.
Drive Plate Holder: 5-8840-4056-0 (J-37872)
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Page 91 of 6020
HEATER AND AIR CONDITIONING 1-57
REASSEMBLY
This illustration is based on the 4J engine model
RTW 510MF000401
Reassembly Steps
1. Compressor
2. Field coil
3. Snap ring
4. Pulley assembly
2. Snap ring
3. Drive plate
7. Plain washer
8. Drive prate bolt
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Page 92 of 6020
1-58 HEATER AND AIR CONDITIONING
Important Operations - Reassembly
RTW 510SH001001
2. Field Coil
Installation field coil. • Align the located portion (1) of the clutch coil and
compressor.
RTW 510SH001101
4. Pulley Assembly
Using pulley installer and drive handle to install the pulley assembly.
Pulley Installer: 5-8840-0118-0 (J-33940)
Drive Handle: 5-8840-0007-0 (J-8092)
RTW 510SH000701
8. Drive Plate Bolt
Using drive plate holder to prevent the drive plate from rotating.
Drive Plate Holder: 5-8840-4056-0 (J-37872) Tighten the bolt to the specified torque. N⋅m (kgf ⋅m/Ib ⋅in)
Torque 13 (1.3/113)
After tightening the bolt, check to be sure the pulley rotates
smoothly.
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Page 115 of 6020
HEATER AND AIR CONDITIONING 1-81
INSPECTION AND REPAIR
840R300005-X
Resistor
As for air-conditioning model, fixed on left (RHD) / right (LHD)
side of the evaporator unit.
As for heater only model, fixed on left (RHD) / right (LHD) side
of the duct placed between blower unit and heater unit.
Replace the resistor with a new on if the coil is found to be
open or if the resistance value deviates from the specified
range.
Terminal Resistance
3 – 2 2.04 Ω
3 – 4 0.88 Ω
3 – 1 0.31 Ω
Blower motor
Check blower motor for smooth rotation.
Connect the battery positive terminal to the No.1 terminal of the
blower motor and negative to the No.2.
Be sure to check to see if the blower motor operates correctly.
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Page 123 of 6020

HEATER AND AIR CONDITIONING 1-89
AIR CONDITIONING CYCLE TROUBLESHOOTING
TROUBLE POSSIBLE CAUSE CORRECTION
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
No cooling or
insufficient
cooling
8. Poor operation of electronic thermostat
•
Check electronic thermostat and replace
as necessary
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
Insufficient
velocity
of cooling air
3. Blower motor does not rotate properly
• Refer to “FAN CONTROL KNOB (FAN
SW ITCH)” 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.
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