check engine TOYOTA LAND CRUISER 1996 J80 User Guide

AC2QC−03
−
AIR CONDITIONING AIR CONDITIONING SYSTEM
AC−3
1996 LAND CRUISER (RM451U)
PROBLEM SYMPTOMS TABLE
Use the table below to help you find the cause of the problem.The numbers i\
ndicate the priority of the likely
cause of the problem. Check each part in order. If necessary, replace these parts.
SymptomSuspect AreaSee page
No blower operation
4. HTR Fuse
5. Heater main relay
6. Blower motor
7. Blower resistor
8. Blower speed control switch
9. Wire harness−
AC−64
AC−52
AC−57
AC−69 −
No air temperature control
1. Engine coolant volume
2. A/C control assembly
3. Water valve−
AC−69
AC−49
No compressor operation
1. Refrigerant volume
2. A.C Fuse
3. Magnetic clutch
4. Compressor
5. Pressure switch
6. Heater main relay
7. Blower speed control switch
8. A/C switch
9. A/C amplifier
10.Thermistor
11. Wire harnessAC−5 −
AC−33
AC−33
AC−61
AC−64
AC−69
AC−69
AC−74
AC−60 −
Compressor operates intermitently
1. Refrigerant volume
2. Pressure switch
3. A/C amplifier
4. Thermistor
5. Wire harnessAC−5
AC−61
AC−74
AC−60 −
No cool air comes out
1. Refrigerant volume
2. Refrigerant pressure
3. Drive belt
4. Magnetic clutch
5. Compressor
6. Pressure switch
7. Thermistor
8. A/C switch
9. A/C amplifier
10.A/C control assembly
11. Wire harnessAC−5
AC−5
AC−15
AC−33
AC−33
AC−61
AC−60
AC−69
AC−74
AC−69 −
Cool air comes out only at high engine rpm
1. Refrigerant volume
2. Drive bel
3. Magnetic clutch
4. Compressor
5. Condenser
6. Receiver
7. Expansion valve
8. Evaporator
9. Thermistor
10.A/C amplifier
11. Wire harnessAC−5
AC−15
AC−33
AC−33
AC−42
AC−39
AC−47
AC−45
AC−60
AC−74 −
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N14063
AC2QD−01
I01386
−
AIR CONDITIONING AIR CONDITIONING SYSTEM
AC−5
1996 LAND CRUISER (RM451U)
ON−VEHICLE INSPECTION
1. INSPECT REFRIGERANT VOLUME
Observe the sight glass on the liquid tube.
Test conditions:
Running engine at 1,500 rpm
Blower speed control switch set at ”HI”
A/C switch ON
Temperature control set at ”MAX. COOL”
Fully open doors
ItemSymptomAmount of refrigerantRemedy
1Bubbles present in sight glassInsufficient*
1. Check for gas leakage with gas leak
tester and repair if necessary
2. Add refrigerant until bubbles disappear
2No bubbles present in sight glassNone, sufficient or too muchRefer to items 3 and 4
3No temperature difference between compressor inlet and outletEmpty or nearly empty
1. Check for gas leakage with gas leaktester and repair if necessary
2. Add refrigerant until bubbles disappear
4Temperature between compressor inlet and outlet is noticeably differentCorrect or too muchRefer to items 5 and 6
5Immediately after air conditioning is turnedoff, refrigerant in sight glass stays clearToo much
1. Discharge refrigerant
2. Evacuate air and charge proper amount of purified refrigerant
6When air conditioning is turned off,
refrigerant foams and then stays clearCorrect−
*: Bubbles in the sight glass with ambient temperatures higher
than usual can be considered normal if cooling is sufficient.
2. INSPECT REFRIGERAT PRESSURE WITH MANIFOLD
GAUGE SET
This is a method in which the trouble is located by using a man-
ifold gauge set. Read the manifold gauge pressure when the
these conditions are established:
Test conditions:
Temperature at the air inlet with the switch set at RECIRC
is 30 − 35° C (86 − 95° F)
Engine running at 1,500 rpm
Blower speed control switch set at high
Temperature control set at max. cool
HINT:
It should be noted that the gauge indications may vary slightly
due to 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)
SightGlass
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I01390
Condition: Insufficient cooling
I01392
Condition: Insufficient coolingNOTE : These gauge indica-
tions are shown when the
refrigeration system has
been opened and the refrig-
erant charged without vacu-
um purging.
AC−8
−
AIR CONDITIONING AIR CONDITIONING SYSTEM
1996 LAND CRUISER (RM451U)
(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
Charge proper amount of refriger-
ant
(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 insuf ficient
(2) Evacuate air and charge new
refrigerant
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AC−10
−
AIR CONDITIONING AIR CONDITIONING SYSTEM
1996 LAND CRUISER (RM451U)
3. INSPECT IDLE−UP SPEED
(a) Warm up engine
(b) Inspect idle −up speed when the these conditions are es-
tablished:
Blower switch HI
Electrical load OFF
A/C switch ON
Put gear shift in neutral
Magnetic clutch conditionIdle speed
Magnetic clutch not engaged650 ± 50 rpm
Magnetic clutch engaged800 ± 50 rpm
If idle speed is not as specified, check the IAC valve and air in-
take system.
4. INSPECT FOR LEAKAGE OF REFRIGERANT
(a) Perform in these conditions:
Stop engine.
Secure good ventilation (If not, the gas leak detec-
tor may react to volatile gases which are not refrig-
erant, such as evaporated gasoline and exhaust
gas.)
Repeat the test 2 or 3 times.
Make sure that there is some refrigerant remaining
in the refrigeration system.
When compressor is OFF: approximately 392 − 588
KPa (4 − 6 kgf/cm
2, 57 − 35 psi)
(b) Bring the gas leak detector close to the drain hose before
performing the test.
HINT:
After the blower motor is stopped, leave the cooling unit
for more than 15 minutes.
Expose the gas leak detector sensor the under the drain
hose.
When bring the gas leak detector close to the drain hose,
make sure that the gas leak detector does not react to the
volatile gases.
If such reaction is unavoidable, the vehicle must be lifted up.
(c) If gas leak is not detected on the drain hose, remove the
power transistor from the cooling unit. Then insert the gas
leak detector sensor into the unit and perform the test.
(d) Disconnect the connector and leave the pressure switch for approximately 20 minutes. Then bring the gas leak de-
tector close to the pressure switch and perform the test.
(e) Bring the gas leak detector close to the refrigerant lines and perform the test.
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−
AIR CONDITIONING AIR CONDITIONING SYSTEM
AC−13
1996 LAND CRUISER (RM451U)
3. CHARGE REFRIGERANT INTO REFRIGERANT SYS-
TEM
If there is no leak after refrigerant leak check charge, the proper
amount of refrigerant into refrigeration system.
CAUTION:
Never 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 refrig-
erant.
(a) Open the high pressure hand valve fully.
(b) Charge specified amount of refrigerant, then close the high pressure hand valve.
HINT:
A fully charged system is indicated by the sight glass being free
of any bubbles.
4. REMOVE MANIFOLD GAUGE SET
(a) Close both hand valves of manifold gauge set.
(b) Disconnect the quick disconnect adapters from the ser- vice valves.
5. INSTALL CAPS TO SERVICE VALVES ON REFRIGER-
ANT LINES
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CH0086
CorrectWrong
AC2QG−01
N01881
DENSOBorroughs
−
AIR CONDITIONING DRIVE BELT
AC−15
1342
Author: Date:
1996 LAND CRUISER (RM451U)
DRIVE BELT
ON−VEHICLE INSPECTION
1. INSPECT DRIVE BELT’S INSTALLATION CONDITION
Check that drive belt fits properly in the ribbed groves.
2. INSPECT DRIVE BELT TENSION
Using a belt tension gauge, check the drive belt tension.
Belt tension gauge:
DENSO BTG −20 (95506−00020) or
Borroughs No. BT −33−73F
Drive belt tension:
New belt 100−150 lbf
Used belt 60−100 lbf
HINT:
”New belt” refers to a belt which has been used less than
5 minutes on a running engine.
”Used belt” refers to a belt which has been on a running
engine for 5 minutes or more.
After installing the drive belt, check that it fits properly in
the ribbed grooves.
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AC2R5−01
N06158
−
AIR CONDITIONING COMPRESSOR AND MAGNETIC CLUTCH
AC−33
1360
Author: Date:
1996 LAND CRUISER (RM451U)
COMPRESSOR AND MAGNETIC
CLUTCH
ON−VEHICLE INSPECTION
1. INSTALL MANIFOLD GAUGE SET (See page AC−18 )
2. START ENGINE
Run the engine at 1,500 rpm.
3. INSPECT COMPRESSOR FOR METALLIC SOUND
Check if there is a metallic sound from the compressor when the
A/C switch is on.
If metallic sound is heard, replace the compressor assembly.
4. INSPECT REFRIGERANT PRESSURE (See page AC−5 )
5. STOP ENGINE
6. INSPECT VISUALLY FOR LEAKAGE OF REFRIGER- ANT FROM SAFETY SEAL
Using a gas leak detector, check for leakage of refrigerant.
If there is any leakage, replace the compressor assembly.
7. REMOVE MANIFOLD GAUGE SET (See page
AC−19 )
8. MAKE THESE VISUAL CHECKS:
(a) Leakage of grease from the clutch bearing.
(b) Signs of oil on the pressure plate or rotor. Repair or replace, as necessary.
9. INSPECT MAGNETIC CLUTCH BEARING FOR NOISE
(a) Start engine.
(b) Check for abnormal noise from near the compressor when the A/C switch is OFF.
If abnormal noise is being emitted, replace the magnetic clutch.
10. INSPECT MAGNETIC CLUTCH
(a) Disconnect the connector from the magnetic clutch.
(b) Connect the positive (+) lead from the battery to the termi-
nal on the magnetic clutch connector and the negative ( −)
lead to the body ground.
(c) Check that the magnetic clutch is energized.
If operation is not as specified, replace the magnetic clutch.
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AC2R8−01
N04963
AC−38
−
AIR CONDITIONING COMPRESSOR AND MAGNETIC CLUTCH
1996 LAND CRUISER (RM451U)
REASSEMBLY
1. INSTALL COMPRESSOR
(a) Install the compressor with the 4 bolts. Torque: 25 N·m (250 kgf·cm, 18 ft·lbf)
(b) Connect the connector.
2. CONNECT DISCHARGE AND SUCTION HOSES Torque: 10 N·m (100 kgf·cm, 7 ft·lbf)
NOTICE:
Hoses should be connected immediately after the caps
have been removed.
HINT:
Lubricate 2 new O −rings with compressor oil and install the
hoses.
3. INSTALL AND INSPECT DRIVE BELT (See page AC−17 )
4. INSTALL ENGINE UNDER COVER
5. CONNECT NEGATIVE ( −) TERMINAL CABLE TO BAT-
TERY
6. EVACUATE AIR FROM REFRIGERATION SYSTEM
7. CHARGE SYSTEM WITH REFRIGERANT AND IN- SPECT FOR LEAKAGE OF REFRIGERANT
Specified amount:
850 ± 50 g (29.98 ± 1.76 oz.)
Using a gas leak detector, check for leakage of refrigerant.
If there is leakage, check the tightening torque at the joints.
8. INSPECT A/C OPERATION
Reassembly is in the reverse order of disassembly (See
page AC−35 ).
9. CHECK CLEARANCE OF MAGNETIC CLUTCH
(a) Set the dial indicator to the pressure plate of the magnetic
clutch.
(b) Connect the magnetic clutch lead wire to the positive (+) terminal of the battery.
(c) Check the clearance between the pressure plate and ro- tor when connecting the negative ( −) terminal to the bat-
tery.
Standard clearance:
0.5 ± 0.15 mm (0.020 ± 0.0059 in.)
If the clearance is not within the standard clearance, adjust the
clearance using shims to obtain the standard clearance. Shim Thickness:
0.1 mm (0.004 in.)
0.3 mm (0.012 in.)
0.5 mm (0.020 in.)
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AC2RR−01
−
AIR CONDITIONING EXPANSION VALVE
AC−47
1374
Author: Date:
1996 LAND CRUISER (RM451U)
EXPANSION VALVE
ON−VEHICLE INSPECTION
1. CHECK QUANTITY OF GAS DURING REFRIGERATION CYCLE
2. INSTALL MANIFOLD GAUGE SET
3. RUN ENGINE
(a) Run the engine at 1,500 rpm for at least 5 minutes.
(b) Then check that the high pressure reading is 1.37 − 1.57 MPa (14 − 16 kgf/cm
2, 199 − 228 psi).
4. CHECK EXPANSION VALVE
If the expansion valve is faulty, the low pressure reading will drop to 0 kPa (0 kgf/cm
2, 0 psi).
HINT:
When the low pressure drops to 0 kPa (0 kgf/cm
2, 0 psi), feel the receiver’s IN and OUT sides for zero temper-
ature difference.
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N16452
AC2SB−01
Z13470
Low Pressure Side
ON (Continuity)
196 kpa
(2.0 kgf·cm
2, 28 psi)
OFF (No Continuity) High Pressure Side
3,140 kpa
(32.0 kgf·cm2, 455 psi)
OFF (No Continuity)
−
AIR CONDITIONING PRESSURE SWITCH
AC−61
1388
Author: Date:
1996 LAND CRUISER (RM451U)
PRESSURE SWITCH
ON−VEHICLE INSPECTION
1. INSTALL MANIFOLD GAUGE SET
2. DISCONNECT CONNECTOR FROM PRESSURE
SWITCH
3. RUN ENGINE AT APPROX. 1,500 RPM
4. INSPECT PRESSURE SWITCH OPERATION
(a) Connect the positive (+) lead from the ohmmeter to termi-
nal 2 and the negative ( −) lead to terminal 1.
(b) Check continuity between terminals when refrigerant pressure is changed, as shown in the illustration.
If operation is not as specified, replace the pressure switch.
5. STOP ENGINE AND REMOVE MANIFOLD GAUGE
SET
6. CONNECT CONNECTOR TO PRESSURE SWITCH
~11L
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