air condition TOYOTA LAND CRUISER 1996 J80 Workshop Manual

IN04T−19
Vehicle Brought to Workshop
Customer Problem
Analysis
Symptom Confirmation
and Diagnostic Trouble
Code Check
Symptom Simulation
Diagnostic Trouble
Code Chart
Problem Symptoms Table
Circuit Inspection or Parts
Inspection
Repair
Confirmation Test
End
1
2
4 3
5
6 78 Ask the customer about the conditions and the
environment when the problem occurred.
1
Confirm the symptoms and the problem conditions,
and check the diagnostic trouble codes.
(When the problem symptoms do not appear
during confirmation, use the symptom simulation
method described later on.) 2, 3
Check the results obtained in Step 2, then confirm
the inspection procedure for the system or the part
which should be checked using the diagnostic
trouble code chart or the problem symptoms table. 4, 5, 6
Check and repair the affected system or part in
accordance with the instructions in Step 6. 7
After completing repairs, confirm that the problem
has been eliminated.
(If the problem is not reproduced, perform the
confirmation test under the same conditions and
in the same environment as when it occurred for
the first time.) 8
IN−18−
INTRODUCTION HOW TO TROUBLESHOOT ECU CONTROLLED
SYSTEMS
1996 LAND CRUISER (RM451U)
HOW TO PROCEED WITH TROUBLESHOOTING
Carry out troubleshooting in accordance with the procedure on the following page. Here, only the basic pro-
cedure is shown. Details are provided in Diagnostics section, showing the most\
effective methods for each
circuit. Confirm the troubleshooting procedures first for the relevant circuit before beg\
inning troubleshooting
of that circuit.
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Important Points in the Customer Problem Analysis
 What −−−−− Vehicle model, system name
 When −−−−− Date, time, occurrence frequency
 Where −−−−− Road conditions
 Under what conditions? −−−−− Running conditions, driving conditions, weather conditions
 How did it happen? −−−−− Problem symptoms
(Sample) Engine control system check sheet.
ENGINE CONTROL SYSTEM Check Sheet
Customer’s Name
Driver’s Name
Data Vehicle
Brought in
License No.
Model and Model
Year
Frame No.
Engine Model
Odometer Reading
km
miles
Problem Symptoms
Engine does
not Start
Difficult to
Start
Poor Idling
Poor
Drive ability
Engine Stall
Others
Engine does not crankNo initial combustionNo complete combustion
Engine cranks slowly
Other
Incorrect first idleIdling rpm is abnormalHigh ( rpm)Low ( rpm)
Rough idling
Other
HesitationBack fireMuffler explosion (after− fire)Surging
Knocking
Other
Soon after startingAfter accelerator pedal depressed
After accelerator pedal released
During A/C operation
Shifting from N to D
Other
Data Problem
ConstantSometimes ( times per day/month)
Inspector’s
Name
CUSTOMER PROBLEM ANALYSIS CHECK
−
INTRODUCTION HOW TO TROUBLESHOOT ECU CONTROLLED
SYSTEMSIN−19
1996 LAND CRUISER (RM451U)
1. CUSTOMER PROBLEM ANALYSIS
In troubleshooting, the problem symptoms must be confirmed accurately an\
d all preconceptions must be
cleared away in order to give an accurate judgment. To ascertain just what the problem symptoms are, it is
extremely important to ask the customer about the problem and the conditions at t\
he time it occurred.
Important Point in the Problem Analysis:
The following 5 items are important points in the problem analysis. Past pr\
oblems which are thought to be
unrelated and the repair history, etc. may also help in some cases, so as much information as possible s\
hould
be gathered and its relationship with the problem symptoms should be corre\
ctly ascertained for reference
in troubleshooting. A customer problem analysis table is provided in Diagnostics section for each system
for your use.
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DIAGNOSTIC TROUBLE CODE CHECK PROCEDURE
Diagnostic Trouble
Code Check (Make a
note of and then clear) Confirmation
of Symptoms
Diagnostic Trouble
Code Check
Problem Condition
Diagnostic Trouble
Code Display Problem symptoms
exist
Same diagnostic
trouble code is
displayed Problem is
still occurring in the diagnostic
circuit
Normal code is
displayed The problem is still occurring in a place
other than in the diagnostic circuit
(The diagnostic trouble code displayed
first is either for a past problem or it is a
secondary problem)
No problem
symptoms exist
The problem occurred in the diagnostic
circuit in the past
Normal Code Display Problem symptoms
existNormal code is
displayed The problem is still occurring in a place
other than in the diagnostic circuit
No problem
symptoms exist
Normal code is
displayed The problem occurred in a place other
than in the diagnostic circuit in the past
IN−20−
INTRODUCTION HOW TO TROUBLESHOOT ECU CONTROLLED
SYSTEMS
1996 LAND CRUISER (RM451U)
2. SYMPTOM CONFIRMATION AND DIAGNOSTIC TROUBLE CODE CHECK
The diagnostic system in the LAND CRUISER fulfills various functions. The first functio\
n is the Diagnostic
Trouble Code Check in which a malfunction in the signal circuits to the ECU is stored in co\
de in the ECU
memory at the time of occurrence, to be output by the technician during troubl\
eshooting. Another function
is the Input Signal Check which checks if the signals from various switc\
hes are sent to the ECU correctly.
By using these check functions, the problem areas can be narrowed down qui\
ckly and troubleshooting can
be performed ef fectively. Diagnostic functions are incorporated in the following systems in the LAND CRUIS-
ER.
SystemDiagnostic Trouble
Code CheckInput Signal Check(Sensor Check)Diagnostic Test
Mode (Active Test)
1. Engine
(with Check Mode)
2. Automatic T ransmission
(with Check Mode)
3. Anti− Lock Brake System
4. Supplemental Restraint System
5. Cruise Control System
In diagnostic trouble code check, it is very important to determine whethe\
r the problem indicated by the diag-
nostic trouble code is still occurring or occurred in the past but returned to\
normal at present. In addition,
it must be checked in the problem symptom check whether the malfunction \
indicated by the diagnostic
trouble code is directly related to the problem symptom or not. For this reason, the \
diagnostic trouble codes
should be checked before and after the symptom confirmation to determine the curre\
nt conditions, as shown
in the table below. If this is not done, it may, depending on the case, result in unnecessary troubleshooting
for normally operating systems, thus making it more difficult to locate the problem, or in repairs not pertinent
to the problem. Therefore, always follow the procedure in correct order an\
d perform the diagnostic trouble
code check.
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V07268
VIBRATION METHOD: When vibration seems to be the major cause.
CONNECTORS
WIRE HARNESS
PARTS AND SENSOR 1
Slightly shake the connector vertically and horizontally.
Slightly shake the wire harness vertically and horizontally.
The connector joint, fulcrum of the vibration, and body
through portion are the major areas to be checked thorough-
ly.
Apply slight vibration with a finger to the part of the sensor
considered to be the pr oblem cause and check that the mal-
function occurs. Shake Slightly
Swing SlightlyVibrate Slightly
HINT:
Applying strong vibration to relays may result in open relays.
IN−22
−
INTRODUCTION HOW TO TROUBLESHOOT ECU CONTROLLED
SYSTEMS
1996 LAND CRUISER (RM451U)
3. SYMPTOM SIMULATION
The most dif ficult case in troubleshooting is when there are no problem symptoms occurring. In such\
cases,
a thorough customer problem analysis must be carried out, then simulate \
the same or similar conditions and
environment in which the problem occurred in the customer’s vehicle. No matter how much experience a
technician has, or how skilled he may be, if he proceeds to troubleshoot without c\
onfirming the problem
symptoms he will tend to overlook something important in the repair operation an\
d make a wrong guess
somewhere, which will only lead to a standstill. For example, for a problem which only occurs \
when the en-
gine is cold, or for a problem which occurs due to vibration caused by the road during\
driving, etc., the prob-
lem can never be determined so long as the symptoms are confirmed with t\
he engine hot condition or the
vehicle at a standstill. Since vibration, heat or water penetration (moisture) is l\
ikely cause for problem which
is difficult to reproduce, the symptom simulation tests introduced here are ef\
fective measures in that the ex-
ternal causes are applied to the vehicle in a stopped condition.
Important Points in the Symptom Simulation Test:
In the symptom simulation test, the problem symptoms should of course be c\
onfirmed, but the problem area
or parts must also be found out. To do this, narrow down the possible problem circuits according to the symp-
toms before starting this test and connect a tester beforehand. After that, \
carry out the symptom simulation
test, judging whether the circuit being tested is defective or normal and also confirming the \
problem symp-
toms at the same time. Refer to the problem symptoms table for each syst\
em to narrow down the possible
causes of the symptom.
FI2331
FI2332
FI2330
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B02389B02390
HEAT METHOD: When the problem seems to occur when the suspect area is heated.
2
NOTICE: 3 WATER SPRINKLING METHOD:
(1)
(2)
4 OTHER: When a malfunction seems to occur when electrical load is excessive. When the malfunction seems to occur on a rainy day or in a
high
−humidity condition.
Heat the component that is the likely cause of the malfunction
with a hair dryer or similar object. Check to see if the
malfunction
occurs.
Sprinkle water onto the vehicle and check to see if the malfunc-
tion occurs.
Turn on all electrical loads including the heater blower, head
lights, rear window defogger, etc. and check to see if the mal-
function occurs. ON
HINT:
If a vehicle is subject to water leakage, the leaked water may
contaminate
the ECU. When testing a vehicle with a water leak-
age problem, special caution must be taken.
Malfunc-
tion
Do not heat to more than 60 °C (140° F). (Temperature
is limited not to damage the components.)
Do not apply heat directly to parts in the ECU.
(1)
(2)
Never sprinkle water directly into the engine compart-
ment, but indirectly change the temperature and hu-
midity by applying water spray onto the radiator front
surface.
Never apply water directly onto the electronic compo-
nents.
NOTICE:
−
INTRODUCTION HOW TO TROUBLESHOOT ECU CONTROLLED
SYSTEMSIN−23
1996 LAND CRUISER (RM451U)
FI2334
FI6649
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IN0CI−02
IN−38
−
INTRODUCTION TERMS
1996 LAND CRUISER (RM451U)
GLOSSARY OF SAE AND TOYOTA TERMS
This glossary lists all SAE− J1930 terms and abbreviations used in this manual in compliance with SAE\
rec-
ommendations, as well as their TOYOTA equivalents.
SAE
ABBREVIATIONSSAE TERMSTOYOT A TERMS
( ) −−ABBREVIA TIONS
A/CAir ConditioningAir Conditioner
ACLAir CleanerAir Cleaner, A/CL
AIRSecondary Air InjectionAir Injection (AI)
APAccelerator Pedal−
B+Battery Positive Voltage+B, Battery Voltage
BAROBarometric PressureHAC
CACCharge Air CoolerIntercooler
CARBCarburetorCarburetor
CFIContinuous Fuel Injection−
CKPCrankshaft PositionCrank Angle
CLClosed LoopClosed Loop
CMPCamshaft PositionCam Angle
CPPClutch Pedal Position−
CTOXContinuous T rap Oxidizer−
CTPClosed Throttle PositionLL ON, Idle ON
DFIDirect Fuel Injection (Diesel)Direct Injection (DI)
DIDistributor Ignition−
DLC1
DLC2
DLC3Data Link Connector 1
Data Link Connector 2
Data Link Connector 31: Check Connector
2: Total Diagnosis Comunication Link (TDCL)
3: OBD II Diagnostic Connector
DTCDiagnostic Trouble CodeDiagnostic Code
DTMDiagnostic Test Mode−
ECLEngine Control Level−
ECMEngine Control ModuleEngine ECU (Electronic Control Unit)
ECTEngine Coolant T emperatureCoolant Temperature, Water Temperature (THW)
EEPROMElectrically Erasable Programmable Read Only Memory
Electrically Erasable Programmable Read Only Memory
(EEPROM),
Erasable Programmable Read Only Memory (EPROM)
EFEEarly Fuel EvaporationCold Mixture Heater (CMH), Heat Control Valve (HCV)
EGRExhaust Gas RecirculationExhaust Gas Recirculation (EGR)
EIElectronic IgnitionTOYOTA Distributorless Ignition (TDI)
EMEngine ModificationEngine Modification (EM)
EPROMErasable Programmable Read Only MemoryProgrammable Read Only Memory (PROM)
EVAPEvaporative EmissionEvaporative Emission Control (EVAP)
FCFan Control−
FEEPROMFlash Electrically Erasable Programmable
Read Only Memory−
FEPROMFlash Erasable Programmable Read Only Memory−
FFFlexible Fuel−
FPFuel PumpFuel Pump
GENGeneratorAlternator
GNDGroundGround (GND)
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AC2810
AC2QA−01
AC2811
N11084
Wrong Okay
LO HI LOHI
−
AIR CONDITIONING AIR CONDITIONING SYSTEM
AC−1
1328
Author: Date:
1996 LAND CRUISER (RM451U)
AIR CONDITIONING SYSTEM
PRECAUTION
1. DO NOT HANDLE REFRIGERANT IN AN ENCLOSED
AREA OR NEAR AN OPEN FLAME
2. ALWAYS WEAR EYE PROTECTION
3. BE CAREFUL THAT LIQUID REFRIGERANT DOES NOT GET IN YOUR EYES OR ON YOUR SKIN
If liquid refrigerant gets in your eyes or on your skin:
(a) Wash the area with lots of cool water.
CAUTION:
Do not rub your eyes or skin.
(b) Apply clean petroleum jelly to the skin.
(c) Go immediately to a physician or hospital for professional treatment.
4. NEVER HEAT CONTAINER OR EXPOSE IT TO NAKED
FLAME
5. BE CAREFUL NOT TO DROP CONTAINER AND NOT TO APPLY PHYSICAL SHOCKS TO IT
6. DO NOT OPERATE COMPRESSOR WITHOUT ENOUGH REFRIGERANT IN REFRIGERANT SYSTEM
If there is not enough refrigerant in the refrigerant system oil lu-
brication will be insuf ficient and compressor burnout may occur,
so take care to avoid this.
7. DO NOT OPEN HIGH PRESSURE MANIFOLD VALVE WHILE COMPRESSOR IS OPERATING
If the high pressure valve is opened, r efrigerant flows in the re-
verse direction and could cause the charging cylinder to rup-
ture, so open and close the only low pressure valve.
8. BE CAREFUL NOT TO OVERCHARGE SYSTEM WITH
REFRIGERANT
If refrigerant is overcharged, it causes problems such as insuffi-
cient cooling, poor fuel economy, engine overheating etc.
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AC−2
−
AIR CONDITIONING AIR CONDITIONING SYSTEM
1329
Author: Date:
1996 LAND CRUISER (RM451U)
9. SUPPLEMENTAL RESTRAINT SYSTEM (SRS)
The LAND CRUISER is equipped with an SRS (Spplemental
Restraint System)such as the driver airbag and passenger air
bag. Failure to carry out service operations in the correct se-
quence could cause the SRS to unexpectedly deployed during
servicing, possibly leading to a serious accident. Further, if a
mistake is made in servicing the SRS, it is possible the SRS may
fail to operate when required. Before servicing (including re-
moval or installation of parts, inspection or replacement), be
sure to read the following item carefully, then follow the correct
procedure described in the repair manual.
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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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AC−4
−
AIR CONDITIONING AIR CONDITIONING SYSTEM
1996 LAND CRUISER (RM451U)
Insuf
ficient cooling
1. Refrigerant volume
2. Drive belt
3. Magnetic clutch
4. Compressor
5. Condenser
6. Receiver
7. Expansion valve
8. Evaporator
9. Refrigerant line
10.Pressure switch
11. A/C amplifier
12.A/C control assemblyAC−5
AC−15
AC−33
AC−33
AC−42
AC−39
AC−47
AC−45
AC−20
AC−61
AC−74
AC−69
No engine idle up when A/C switch ON
1. A/C amplifier
2. ECM
3. Wire harnessAC−74 −
−
No warm air comes out
1. Engine coolant volume
2. A/C control assembly
3. Water valve
4. Heater radiator−
AC−69
AC−49
AC−46
A/C indicator does not light up when mode lever at DEF. position
1. Defroster mode switch
2. A/C switch
3. Wire harnessAC−69
AC−69 −
Rear heater:
SymptomSuspect AreaSee page
No blower operation
1. RR HTR Fuse
2. Rear heater relay
3. Rear heater switch
4. Rear blower motor
5. Rear blower resistor−
AC−65
AC−77
AC−55
AC−58
No warm air come out1. Engine coolant volume
2. Rear heater radiator−
AC−46
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