coolant temperature TOYOTA LAND CRUISER 1996 J80 Workshop Manual

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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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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N06549
AC2SH−01
V02084OFFON
103 °C (217° F)
108
°C (226° F)
−
AIR CONDITIONING ENGINE COOLANT TEMPERATURE (ECT) CUT
RELAYAC−67
1394
Author: Date:
1996 LAND CRUISER (RM451U)
ENGINE COOLANT
TEMPERATURE (ECT) CUT RELAY
INSPECTION
INSPECT SWITCH CONTINUITY
Check the continuity betweeen terminals of the switch, as
shown in the chart below.
If continuity is not as specified, replace the switch.
_tf
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BE−4
−
BODY ELECTRICAL BODY ELECTRICAL SYSTEM
1996 LAND CRUISER (RM451U)
Back−
Up light remains on.
1. Park/Neutral Position Switch (A/T)
2. Wire Harness−
−
Only one light does not light up.1. Bulb
2. Wire Harness−
−
STOP LIGHT SYSTEM
SymptomSuspect AreaSee page
Stop light does not light up.
1. STOP Fuse (I/P F/B)
2. Stop Light Switch
3. Bulb
4. Wire Harness−
BE−25 −
−
Stop light remains always on.1. Stop Light Switch
2. Wire HarnessBE−25−
Only one light does not light up.1. Wire Harness
2. Bulb−
−
WIPER AND WASHER SYSTEM
SymptomSuspect AreaSee page
Wipers do not operate or return to off position.
1. WIPER Fuse (I/P F/B)
2. Wiper Switch
3. Wiper Motor
4. Wiper Relay
5. Wire HarnessBE−27
BE−27
BE−27
BE−27
−
Wipers do not operate in MIST.
1. Wiper Switch
2. Wiper Motor
3. Wiper Relay
4. Wire HarnessBE−27
BE−27
BE−27
−
Wipers do not operate in INT.
1. Wiper Switch
2. Wiper Motor
3. Wiper Relay
4. Wire HarnessBE−27
BE−27
BE−27−
Washer does not operate.
1. Washer Hose or Nozzle Clogged
2. Washer Switch
3. Washer Motor
4. Wire Harness−
BE−27
BE−27 −
METER, GAUGES AND ILLUMINATION:
COMBINATION METER
SymptomSuspect AreaSee page
Tachometer, speedometer, engine coolant temperature gauge and
fuel gauge do not operate.1. GAUGE Fuse (I/P F/B)
2. Meter Circuit
3. Wire Harness−
BE−32 −
Speedometer does not operate.
1. No.1 Vehicle Speed Sensor
2. Speedometer Driven Gear and Drive Gear
3. Meter Circuit
4. Wire HarnessBE−34−
BE−32 −
Tachometer does not operate.
1. Meter Circuit
2. Igniter
3. Wire HarnessBE−32−
−
Tachometer does not operate.
1. Meter Circuit
2. Igniter
3. Wire HarnessBE−32−
−
Voltmeter does not operate.1. Voltmeter Receiver Gauge
2. Wire HarnessAT −6
−
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−
BODY ELECTRICAL BODY ELECTRICAL SYSTEM
BE−5
1996 LAND CRUISER (RM451U)
Fuel gauge does not operate or abnormal operation.
1. Fuel Receiver Gauge
2. Fuel Sender Gauge
3. Meter Circuit
4. Wire HarnessBE−34
BE−34
BE−32
−
Engine coolant temperature gauge does not operation or
abnormal operate.
1. Engine Coolant Temperature Receiver Gauge
2. Engine Coolant Temperature Sender Gauge
3. Meter Circuit
4. Wire HarnessBE−34
BE−34
BE−32−
Oil pressure gauge does not operate or abnormal operation.
1. Oil Pressure Receiver Gauge
2. Oil Pressure Sender Gauge
3. Meter Circuit
4. Wire HarnessBE−34
BE−34
BE−34−
All illumination lights do not light up.
1. TAIL Fuse (I/P F/B)
2. Light Control Rheostat
3. Wire Harness−
BE−34 −
Brightness does not change even when rheostat turned.1. Bulb
2. Wire Harness−
−
Only one illumination light does not light up.1. Bulb
2. Wire Harness−
−
WARNING LIGHTS:
COMBINATION METER
SymptomSuspect AreaSee page
Warning lights do not lights up.
(Except discharge, SRS and door open)1. GAUGE Fuse (I/P F/B)
2. Meter Circuit
3. Wire Harness−
BE−32 −
Brake warning light does not light up.
1. Bulb
2. Brake Fluid Level Switch
3. Parking Brake Switch
4. Meter Circuit
5. Wire Harness−
BE−34
BE−34
BE−32 −
Open door warning light does not light up.
1. Bulb
2. Door Courtesy Switch
3. DOME Fuse (No.2 R/B)
4. Meter Circuit
5. Wire Harness−
BE−21
BE−21 −
−
−
SRS warning light does not light up
1. Bulb
2. Airbag Sensor Assembly
3. ECU− B Fuse (I/P F/B)
4. Meter Circuit
5. Wire Harness−
−
−
BE−32 −
Discharge warning light does not light up.
1. Bulb
2. IGN Fuse (No.1 J/B)
3. Generator
4. Meter Circuit
5. Wire Harness−
−
−
BE−32 −
Seat belt warning light does not light up.
1. Bulb
2. Seat Belt Buckle Switch
3. Seat Belt Warning Relay (I/P F/B)
4. Meter Circuit
5. Wire Harness−
BE−34 −
BE−32 −
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Engine Coolant
Temperature
Gauge
Ignition Switch
Battery Sender
Gauge
Z06815
Engine
Coolant T emperature Gauge
Ignition
Switch Tester Bulb
(3.4 W)
Battery
BE1222
Oil Pressure Gauge
Ignition
Switch Sender
Gauge
Battery
−
BODY ELECTRICAL COMBINATION METER
BE−37
1996 LAND CRUISER (RM451U)
11. INSPECT ENGINE COOLANT TEMPERATURE RE-
CEIVER GAUGE OPERATION
(a) Disconnect the connector from the sender gauge.
(b) Turn the ignition switch ON, and check that the receiver
gauge needle indicates COOL.
(c) Ground terminal on the wire harness side connector through a 3.4 W test bulb.
(d) Turn the ignition switch ON, and check that the bulb lights up and the receiver gauge needle moves to the hot side.
If operation is as specified, replace the sender gauge. Then re-
check the system.
If operation is not as specified, measure the receiver gauge re-
sistance.
12. INSPECT ENGINE COOLANT TEMPERATURE RE-
CEIVER GAUGE RESISTANCE
Measure the resistance between terminals.
Between terminalsResistance (Ω )
A − B71 − 79
A − C117 − 141
B − C185 − 215
HINT:
Connect the test leads so that the current from the ohmmeter
can flow according to the above order. This circuit include the
diode.
If resistance value is not as specified, replace the receiver
gauge.
13. INSPECT OIL PRESSURE RECEIVER GAUGE OP-
ERATION
(a) Disconnect the connector from the sender gauge.
(b) Turn the ignition switch ON, and check that the receiver
gauge needle indicates LOW.
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N09214
DI−4
−
DIAGNOSTICS ENGINE
1996 LAND CRUISER (RM451U)
The diagnosis system operates in normal mode
during normal vehicle use. It also has a check mode
for technicians to simulate malfunction symptoms
and troubleshoot. Most DTC use 2 trip detection
logic* to prevent erroneous detection, and ensure
thorough malfunction detection. By switching the
ECM to check mode when troubleshooting, the
technician can cause the MIL to light up for a mal-
function that is only detected once or momentarily
(TOYOTA hand−held tester only) (See step 2).
*2 trip detection logic:
When a logic malfunction is first detected, the mal-
function is temporarily stored in the ECM memory.
If the same malfunction is detected again during the
second drive test, this second detection causes the
MIL to light up.
The 2 trip repeats the same mode a 2nd time (How-
ever, the IG switch must be turned OFF between the
1st trip and 2nd trip.).
Freeze frame data:
Freeze frame data records the engine condition
when a misfire (DTC P0300 − P0306) or fuel trim
malfunction (DTC P0171, P0172) or other malfunc-
tion (first malfunction only), is detected.
Because freeze frame data records the engine
conditions (fuel system, calculator load, engine
coolant temperature, fuel trim, engine speed, ve-
hicle speed, etc.) when the malfunction is detected,
when troubleshooting it is useful for determining
whether the vehicle was running or stopped, the en-
gine warmed up or not, the air− fuel ratio lean or rich,
etc. at the time of the malfunction.
Priorities for troubleshooting:
If troubleshooting priorities for multiple DTCs are given in the
applicable diagnostic chart, these should be followed.
If no instructions are given troubleshoot DTCs according to the
following priorities. (1) DTC other than fuel trim malfunction (DTC P0171,
P0172), EGR (DTC P0401, P0402), and misfire
(DTC P0300 − P0306).
(2) Fuel trim malfunction (DTC P0171, P0172), and EGR (DTC P0401, P0402).
(3) Misfire (DTC P0300 − P0306).
(b) Check the DLC3. The vehicle’s ECM uses V.P.W. (V ariable Pulse Width) for
communication to comply with SAE J1850. The terminal
arrangement of DLC3 complies with SAE J1962 and
matches the V.P.W. format.
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A00484
Intake Air Temp. Sensor
(Inside the mass air flow meter)
3
4 L−Y
BR−B 5V
ECM
E5
E5
THA
E1
E2
P22420
3
9 R
−
DIAGNOSTICS ENGINE
DI−27
1996 LAND CRUISER (RM451U)
WIRING DIAGRAM
INSPECTION PROCEDURE
HINT:
If DTCs P0110 (Intake Air Temp. Circuit Malfunction), P0115 (Engine Coolant Temp. Circuit Malfunction),
P0120 (Throttle/Pedal Position Sensor/Switch ”A” Circuit Malfunction)\
are output simultaneously, E2 (Sen-
sor Ground) may be open.
1 Connect the OBD II scan tool or TOYOTA hand −held tester, and read value of
intake air temperature.
PREPARATION:
(a) Remove the fuse cover on the instrument panel.
(b) Connect the OBD II scan tool or TOYOTA hand−held tester to DLC3.
(c) Turn ignition switch ON and OBD II scan tool or TOYOTA hand−held tester main switch ON.
CHECK:
Read temp. value on the OBD II scan tool or TOYOTA hand −held tester.
OK:
Same as actual intake air temp.
HINT:
If there is open circuit, push OBD II scan tool or TOYOTA hand− held tester indicates − 40° C (− 40°F).
If there is short circuit, OBD II scan tool or TOYOTA handheld tester indicates 140° C (284°F) or more.
NG − 40° C (− 40 °F) ....Go to step 2.
140 °C (284°F) or more ....Go to step 4.
OK
Check for intermittent problems
(See page DI−3 ).
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A00485
Engine Coolant Temp. Sensor2
1 R−W
BR−B 5V
ECM
E5
E5
THW
E1
E2
4
9
P22421
DI−30
−
DIAGNOSTICS ENGINE
1996 LAND CRUISER (RM451U)
DTC P0115 Engine Coolant Temp. Circuit Malfunction
CIRCUIT DESCRIPTION
A thermistor built into the engine coolant temperature sensor changes the\
resistance value according to the
engine coolant temperature.
The structure of the sensor and connection to the ECM is the same as in the\
intake air temp. circuit malfunc-
tion shown on page DI−26.
If the ECM detects the DTC P0115, it operates the fail safe function in which the engine coolant temp.\
is
assumed to be 80 °C (176
°F).
DTC No.Detection ItemTrouble Area
P0115Open or short in engine coolant temp. sensor circuit
 Open or short in engine coolant temp. sensor circuit
 Engine coolant temp. sensor
 ECM
HINT:
After confirming DTC P0115 use the OBD II scan tool or TOYOTA hand −held tester to confirm the engine
coolant temp. from CURRENT DATA.
Temp. DisplayedMalfunction
− 40° C (− 40°F)Open circuit
140°C (284°F) or moreShort circuit
WIRING DIAGRAM
DI5P5−02
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A00156
ON
Engine Coolant
Temp. Sensor ECM
5V
4
9
2
1
E2
E1
THW
E5
E5
BE6653
FI7055
−
DIAGNOSTICS ENGINE
DI−31
1996 LAND CRUISER (RM451U)
INSPECTION PROCEDURE
HINT:
If DTC is P0110 (Intake Air Temp. Circuit Malfunction), P0115 (Engine Coolant Temp. Circuit Malfunction),
P0120 (Throttle/Pedal Position Sensor/Switch ”A” Circuit Malfunction)\
are output simultaneously, E2 (Sen-
sor Ground) may be open.
1 Connect the OBD II scan tool or TOYOTA hand −held tester, and read value of
engine coolant temperature.
PREPARATION:
(a) Remove the fuse cover on the instrument panel.
(b) Connect the OBD II scan tool or TOYOTA hand−held tester to the DLC3.
(c) Turn ignition switch ON and push the OBD II scan tool or TOYOTA hand−held tester main switch ON.
CHECK:
Read temperature value on the OBD II scan tool or TOYOTA hand −held tester.
OK:
Same as actual engine coolant temperature.
HINT:
If there is open circuit, OBD II scan tool or TOYOTA hand−held tester indicates − 40°C (− 40 °F).
If there is short circuit, OBD II scan tool or T OYOTA hand−held tester indicates 140 °C (284 °F) or more.
NG −40°C ( −40° F) ... Go to step 2.
140 °C (284° F) or more ... Go to step 4.
OK
Check for intermittent problems
(See page DI−3 ).
2 Check for open in harness or ECM.
PREPARATION:
(a) Disconnect the engine coolant temp. sensor connector.
(b) Connect sensor wire harness terminals together.
(c) Turn ignition switch ON.
CHECK:
Read temp. value on the OBD II scan tool or TOYOTA hand −
held tester.
OK:
Temp. value: 140° C (284°F) or more
OK Confirm good connection at sensor. If OK, replace engine coolant temp. sensor.
NG
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