Page 13 of 3115
AC1HN-04
N13793
Charging Cylinder High Pressure
Service Valve Low Pressure
Service ValvePush
Air
N13792
Gas Leak
Detector
- AIR CONDITIONINGAIR CONDITIONING SYSTEM
AC-1 1
2736 Author: Date:
2004 LAND CRUISER (RM1071U)
CHARGING
1. INSTALL CHARGING CYLINDER
HINT:
When handling the charging cylinder, always follow the direc-
tions given in the instruction manual.
(a) Charge the proper amount of refrigerant into the charging
cylinder.
(b) Connect the center hose to the charging cylinder.
CAUTION:
Do not open both high and low hand valves of manifold
gauge set.
(c) Open the valve of the charging cylinder.
(d) Press the valve core on the side of manifold gauge and
expel the air inside the center hose.
2. INSPECT REFRIGERATION SYSTEM FOR LEAKS
(a) Open the high pressure hand valve and the charge refrig-
erant.
(b) When the low pressure gauge indicates 98 kPa
(1 kgf/cm
2, 14 psi), close the high pressure hand valve.
(c) Using a gas leak detector, check the system for any leak-
age.
If leaks are found, repair the faulty component or connection.
CAUTION:
Use the refrigerant recovery/ recycling machine to recover
the refrigerant whenever replacing parts.
Page 14 of 3115
N13790
Low Pressure
Service Valve
High Pressure
Service Valve
I08298
Properly
Charged
Insufficiently
Charged
AC-12
- AIR CONDITIONINGAIR CONDITIONING SYSTEM
2737 Author: Date:
2004 LAND CRUISER (RM1071U)
3. CHARGE REFRIGERANT INTO REFRIGERATION
SYSTEM
If there is no leak after refrigerant leak check, charge the proper
amount of refrigerant into the refrigeration system.
CAUTION:
Do not run the engine when charging the system
through the high pressure side.
Do not open the low pressure hand valve when the
system is being charged with liquid refrigerant.
(a) Open the high pressure hand valve fully.
(b) Charge specified amount of refrigerant, then close the
high pressure hand valve.
HINT:
No bubbles in the sight glass indicates that the system is fully
charged.
(c) Partially charge the refrigeration system with refrigerant.
(1) Start engine and race engine at 1,500 rpm.
(2) Set fan speed selector to ºHIº.
(3) Set temperature control to ºMAX. COOLº.
(4) Set air inlet control to ºRECIRCº.
(5) Fully open doors (Sliding roof: closed).
(6) Open the low pressure hand valve.
CAUTION:
Do not open the high pressure hand valve.
(d) Charge refrigerant until bubbles disappear and check the
pressure on the gauge through the sight glass.
Page 15 of 3115
AC1HM-04
N13795
Quick Disconnect
Adapter
Charging
Service ValveHose
N13794
Vacuum Pump
Vacuum Pump Adapter
N13791
Low Pressure
Service Valve
Vacuum Pump Adapter High Pressure
Service ValveManifold
Gauge
Set
AC-10
- AIR CONDITIONINGAIR CONDITIONING SYSTEM
2735 Author: Date:
2004 LAND CRUISER (RM1071U)
EVACUATING
1. CONNECT QUICK DISCONNECT ADAPTER TO
CHARGING HOSES
2. REMOVE CAPS FROM SERVICE VALVES ON RE-
FRIGERANT LINES
3. SET ON MANIFOLD GAUGE SET
(a) Close both the hand valves of the manifold gauge set.
(b) Connect the quick disconnect adapters to the service
valves.
4. EVACUATE AIR FROM REFRIGERATION SYSTEM
(a) Connect the vacuum pump adapter to the vacuum pump.
(b) Connect the center hose of the manifold gauge set to the
vacuum pump adapter.
(c) Open both the high and low hand valves and run the vacu-
um pump.
(d) After 10 minutes or later, check that the low pressure
gauge indicates 750 mmHg (30 in. Hg) minimum.
HINT:
If the reading is 750 mmHg (30 in. Hg) close both hand valves
of the manifold gauge set and stop the vacuum pump.
Check the system for leaks and repair if necessary.
(e) Close both the high and low hand valves and stop the vac-
uum pump.
(f) Leave the system in this condition for at least 5 minutes
and check that there is no gauge indicator.
Page 19 of 3115
I01386
AC-4
- AIR CONDITIONINGAIR CONDITIONING SYSTEM
2729 Author: Date:
2004 LAND CRUISER (RM1071U)
2. INSPECT REFRIGERANT PRESSURE WITH MAN-
IFOLD GAUGE SET
Check the trouble area using a set of manifold gauge set. Read
the manifold gauge pressure when following conditions are de-
tected.
Test conditions:
Temperature at the air inlet with the switch set
at RECIRC is 30 - 35 °C (86 - 95 °F)
Engine running at 2,000 rpm
Fan speed selector at ºHIº position
Temperature control dial on ºCOOLº position
HINT:
It should be noted that the gauge indications may vary depend-
ing on ambient temperature conditions.
(1) Normally functioning refrigeration system.
Gauge reading:
Low pressure side:
0.15 - 0.25 MPa (1.5 - 2.5 kgf/cm
2)
High pressure side:
1.37 - 1.57 MPa (14 - 15 kgf/cm
2)
Page 20 of 3115
I01387
Condition : Periodically cools and then fails to cool
I01388
Condition: Insufficient cooling
- AIR CONDITIONINGAIR CONDITIONING SYSTEM
AC-5
2730 Author: Date:
2004 LAND CRUISER (RM1071U)
(2) Moisture present in refrigeration system.
Symptom seen in
refrigeration systemProbable causeDiagnosisRemedy
During operation, pressure on low
pressure side sometimes become
a vacuum and sometime normal
Moisture entered in refrigeration
system freezes at expansion valve
orifice and temporarily stops cycle,
but normal state is restored after a
time when the ice melts Drier in over-saturated state
Moisture in refrigeration system
freezes at expansion valve orifice
and blocks circulation of refriger-
ant(1) Replace condenser
(2) Remove moisture in cycle
through repeatedly evacuating air
(3) Charge proper amount of new
refrigerant
(3) Insufficient cooling.
Symptom seen in
refrigeration systemProbable causeDiagnosisRemedy
Pressure low on both low and
high pressure sides
Bubbles seen in sight glass con-
tinuously
Insufficient cooling performance
Gas leakage at some place in re-
frigeration system Insufficient refrigerant in system
Refrigerant leaking
(1) Check for gas leakage with gas
leak detector and repair if neces-
sary
(2) Charge proper amount of re-
frigerant
(3) If indicated pressure value is
near 0 when connected to gauge,
create the vacuum after inspecting
and repairing the location of the
leak
Page 21 of 3115
I01389
Condition: Insufficient cooling
I01449
Condition: Does not cool (Cools from time to time in some cases) AC-6
- AIR CONDITIONINGAIR CONDITIONING SYSTEM
2731 Author: Date:
2004 LAND CRUISER (RM1071U)
(4) Poor circulation of refrigerant.
Symptom seen in
refrigeration systemProbable causeDiagnosisRemedy
Pressure low in both low and
high pressure sides
Frost on tube from condenser to
unit
Refrigerant flow obstructed by dirt
in condensercondenser cloggedReplace condenser
(5) Refrigerant does not circulate.
Symptom seen in
refrigeration systemProbable causeDiagnosisRemedy
Vacuum indicated on low pres-
sure side, very low pressure indi-
cated on high pressure side
Frost or dew seen on piping be-
fore and after condenser/ drier or
expansion valve Refrigerant flow obstructed by
moisture or dirt in refrigeration sys-
tem
Refrigerant flow obstructed by
gas leakage from expansion valve
Refrigerant does not circulate
(1) Check expansion valve
(2) Clean out dirt in expansion
valve by blowing with air
(3) Replace condenser
(4) Evacuate air and charge new
refrigerant to proper amount
(5) For gas leakage from expan-
sion valve, replace expansion
valve
Page 22 of 3115
I01390
Condition: Insufficient cooling
I01392
Condition: Insufficient cooling
NOTE : These gauge indica-
tions are shown when the
refrigeration system has
been opened and the refrig-
erant charged without vacu-
um purging.
- AIR CONDITIONINGAIR CONDITIONING SYSTEM
AC-7
2732 Author: Date:
2004 LAND CRUISER (RM1071U)
(6) Refrigerant overcharged or insufficient cooling of
condenser.
Symptom seen in
refrigeration systemProbable causeDiagnosisRemedy
Pressure too high on both low
and high pressure sides
No air bubbles seen through the
sight glass even when the engine
rpm is lowered Unable to develop sufficient per-
formance due to excessive refrig-
eration system
Insufficient cooling of condenser Excessive refrigerant in
cycle " refrigerant over charged
Condenser cooling " condenser
fins clogged or cooling fan faulty
(1) Clean condenser
(2) Check cooling fan with fluid
coupling operation
(3) If (1) and (2) are in normal
state, check amount of refrigerant,
and charge proper amount of re-
frigerant
(7) Air present in refrigeration system.
Symptom seen in
refrigeration systemProbable causeDiagnosisRemedy
Pressure too high on both low
and high pressure sides
The low pressure piping hot to
touch
Bubbles seen in sight glass
Air entered in refrigeration system
Air present in refrigeration sys-
tem
Insufficient vacuum purging
(1) Check compressor oil to see if
it is dirty or insufficient
(2) Evacuate air and charge new
refrigerant
Page 23 of 3115
I01450
Condition: Insufficient cooling
I01393
Condition : Does not cool AC-8
- AIR CONDITIONINGAIR CONDITIONING SYSTEM
2733 Author: Date:
2004 LAND CRUISER (RM1071U)
(8) Expansion valve improperly.
Symptom seen in
refrigeration systemProbable causeDiagnosisRemedy
Pressure too high on both low
and high pressure sides
Frost or large amount of dew on
piping on low pressure side
Trouble in expansion valve
Excessive refrigerant in low
pressure piping
Expansion valve opened too
wide
Check expansion valve, and re-
place if defective
(9) Defective compression compressor.
Symptom seen in
refrigeration systemProbable causeDiagnosisRemedy
Pressure too high on low and
high pressure sides
Pressure too low on high pres-
sure side
Internal leak in compressor
Compression defective
Valve leaking or broken sliding
parts
Repair or replace compressor
