3. INSPECT EACH UP±SHIFT POSITION
(a) Warm up the engine.
Coolant temperature: 176
°F (80°)
(b) Turn the O/D switch to ºONº.
(c) Place the pattern select switch in ºNormalº and the shift
lever into the D range.
(d) During a road test (above 10 km/h or 6 mph) check that volt-
age at the Tt terminal is as indicated below for each up±
shift position.
If the voltage rises from 0V to 7V in the sequence shown,
the control system is okay.
The chart on the left shows the voltmeter reading and cor-
responding gears.
HINT: Determine the gear position by a fight shock or
change in engine rpm when shifting. The lock±up clutch will
turn ON only infrequently during normal 2nd and 3rd gear
operation. To trigger this action, press the accelerator pedal
to 50% or more of its stroke. At less than 50%, the voltage
may change in the sequence 2v ± 4V ± 6V ± 7V. 2. INSPECT BRAKE SIGNAL
(a) Depress the accelerator pedal until the Tt terminal indi-
cates 8V.
(b) Depress the brake pedal and check the voltage read-
ing from the Tt terminal.
Brake pedal depressed ...... 0V
Brake pedal released . . . . . . . . 8V
If not as indicated, there is a malfunction in either the
stop light switch or circuit.
INSPECTION OF ECT OR Tt TERMINAL
VOLTAGE
1. INSPECT THROTTLE POSITION SENSOR SIGNAL
(a) Turn the ignition switch to ON. Do not start the engine.
(b) Connect a voltmeter to terminals Tt and E1.
(c)while slowly depressing the accelerator pedal, check
that Tt terminal voltage rises in sequence.
If the voltage does not change in proportion to the
throttle opening angle, there is a malfunction in the
throttle position sensor or circuit.
± AUTOMATIC TRANSAXLETroubleshooting (Electronic Control System) (A540E and
A540H)AT±215
INSPECTION OF ELECTRONIC CONTROL
COMPONENTS
1. (A540E)
INSPECT VOLTAGE OF TCCS ECU CONNECTOR
(a) Turn on the ignition switch.
(b) Measure the voltage at each terminal.
Coolant temp. 176°F (84°C)
Cruise control main
switch OFFO/D main switch turned OFF O/D main switch turned ON Throttle valve fully closed
Throttle valve fully closed Brake pedal is depressed
Throttle valve fully openMeasuring condition
Brake pedal is released
Throttle valve open
Vehicle movingVehicle moving P, R or N range D, 2 or L range
Standing stillStanding still NORM patternVoltage (V)
PWR pattern Terminal
± AUTOMATIC TRANSAXLE(A540E and A540H)AT±216
3. (A540E)
INSPECT SOLENOID VALVES
(a) Disconnect the connector from Engine and ECT ECU
(b) Measure the resistance between S1, S2, SL and
body ground.
Resistance: 11 ± 15
(e) Apply battery voltage to each terminal.
Check that an operation noise can be heard from
the solenoid.
Center differential control switch AUTO position
Center differential control switch AUTO position Center differential control switch turned OFF
Center differential control switch turned OFF Coolant temp. below 122°F950°0 Throttle valve fully closed to fully open
Coolant temp. above 122°F (50°C0 O/D main switch turned OFF O/D main switch turned ON
Brake pedal is depressed
Brake pedal is releasedMeasuring condition
Except 2 range
Except N range Except P range
Except L range
NORM patternVoltage (V)
PWR pattern Terminal
N range2 range P range
L range
± AUTOMATIC TRANSAXLETroubleshooting (Electronic Control System) (A540E and
A540H)AT±218
The cooling system is composed of the water jacket (inside the cylinder block and cylinder head), radiator,
water pump, thermostat, electric fan, hoses and other components.
Coolant which is heated in the water jacket is pumped to the radiator, through which an electric fan blows air
to cool the coolant as it passes through. Coolant which has been cooled is then sent back to the engine by
the water pump, where it cools the engine.
The water jacket is a network of channels in the shell of the cylinder block and cylinder head through which
coolant passes. It is designed to provide adequate cooling of the cylinders and combustion chambers which
become heated during engine operation.
RADIATOR
The radiator performs the function of cooling the coolant which has passed through the water jacket and be-
come hot, and it is mounted in the front of the vehicle. The radiator consists of an upper tank and lower tank,
and a core which connects the two tanks. The upper tank contains the inlet for coolant from the water jacket
and the filler inlet. It also has a hose attached through which excess coolant or steam can flow. The lower
tank has an outlet and drain cock for the coolant. The core contains many tubes through which coolant flows
from the upper tank to the lower tank as well as cooling fins which radiate heat away from the coolant in the
tubes.
The air sucked through the radiator by the electric fan, as well as the wind generated by the vehicle's travel,
passes through the radiator, cooling the coolant. Models with automatic transmission include an automatic
transmission fluid cooler built into the lower tank of the radiator. A fan with an electric motor is mounted be-
hind the radiator to assist the flow of air through the radiator. The fan operates when the coolant tempera-
ture becomes high in order to prevent it from becoming too high.
RADIATOR CAP
The radiator cap is a pressure type cap which seals the radiator, resulting in pressurization of the radiator as
the coolant expands. The pressurization prevents the coolant from boiling even when the coolant tempera-
ture exceeds 100°C (212°F). A relief valve (pressurization valve) and a vacuum valve (negative pressure
valve) are built into the radiator cap. The relief valve opens and lets steam escape through the overflow pipe
when the pressure generated inside the cooling system exceeds the limit (coolant temperature: 110 ±
120°C, 230 ± 248°F, pressure; 0.3 ±1.0 kg/cm
2, 4.3 ±14.2 psi, 29.4 ± 98.1 kPa). The vacuum valve opens to
alleviate the vacuum which develops in the coolant system after the engine is stopped and the coolant tem-
perature drops.
The valves's opening allows the coolant in the reservoir tank to return to the cooling system.
RESERVOIR TANK
The reservoir tank is used to catch coolant which overflows the cooling system as a result of volumetric ex-
pansion when the coolant is heated. The coolant in the reservoir rank returns to the radiator when the cool-
ant temperature drops, thus keeping the radiator full at all times and avoiding needless coolant loss. Check
the reservoir tank level to find out if the coolant needs to be replenished.
WATER PUMP
The water pump is used for forced circulation of coolant through the cooling system. It is mounted on the
front of the cylinder block and driven by a timing belt.
THERMOSTAT
The thermostat has a wax type by±pass valve and is mounted in the water inlet housing. The thermostat in-
cludes a type of automatic valve operated by fluctuations in the coolant temperature. This valve closes when
the coolant temperature drops, preventing the circulation of coolant through the engine and thus permitting
the engine to warm up rapidly. The valve opens when the coolant temperature has risen, allowing the cir-
culation of coolant. Wax inside the thermostat expands when heated and contracts when cooled. Heating
the wax thus generates pressure which overpowers the force of the spring which keeps±the valve closed,
thus opening the valve. When the wax cools, its contraction causes the force of the spring to take effect
once more, closing the valve. The thermostat in this engine operates at a temperature of 82°C (180°F).
± COOLING SYSTEMDescriptionCO±3
3. (3S±FE)
REPLACE ENGINE COOLANT
(a) Remove the radiator cap.
CAUTION: To avoid the danger of being burned, do not re-
move it while the engine and radiator are still hot
as fluid and steam can be blown out under pressure.
(b) Drain the coolant from the .radiator and engine drain cocks.
(Engine drain cock at the right rear of engine block.)
(c) Close the drain cocks.
Torque (Engine drain cock):
130 kg±cm (9 ft±Ib, 13 N±m) HINT: If the engine tends to overheat, removal of the
thermostat will adversely effect cooling efficiency.
CHECK AND REPLACEMENT OF
ENGINE COOLANT
1. CHECK ENGINE COOLANT LEVEL AT RESERVE TANK
The coolant level should be between the ºLOWº and
ºFULLº lines.
If low, check for leaks and add coolant up to the ºFULLº
line.
Dirt, leaves or insects on radiator or condenser
Hoses, Water pump, thermostat housing, radiator,
heater, core, plugs or head gasket leakage
Thermostat faulty
Incorrect ignition timing
Electric cooling system faulty
Radiator hose plugged or rotted
Water pump faulty
Radiator plugged or cap faulty
Cylinder head or block cracked or water passage
clogged
2. CHECK ENGINE COOLANT QUALITY
There should not be any excessive deposits of rust or scales
around the radiator cap or radiator filler hole, and the cool-
ant should be free from oil.
If excessively dirty, replace the coolant.
Check thermostat
Reset tinning
Inspect electric cooling system
Replace hose
Replace water pump
Check radiator and cap
Repair as necessary
TROUBLESHOOTING
CO±12, 13
IG±17, 20
CO±20, 22 Clean radiator or condenser
Repair as necessary Engine overheats
Possible causeRemedy Problem
CO±6, 9 Page
± COOLING SYSTEM
TroubleshootingCO±4
3. (3S±FE)
REPLACE ENGINE COOLANT
(a) Remove the radiator cap.
CAUTION: To avoid the danger of being burned, do not re-
move it while the engine and radiator are still hot
as fluid and steam can be blown out under pressure.
(b) Drain the coolant from the .radiator and engine drain cocks.
(Engine drain cock at the right rear of engine block.)
(c) Close the drain cocks.
Torque (Engine drain cock):
130 kg±cm (9 ft±Ib, 13 N±m) HINT: If the engine tends to overheat, removal of the
thermostat will adversely effect cooling efficiency.
CHECK AND REPLACEMENT OF
ENGINE COOLANT
1. CHECK ENGINE COOLANT LEVEL AT RESERVE TANK
The coolant level should be between the ºLOWº and
ºFULLº lines.
If low, check for leaks and add coolant up to the ºFULLº
line.
Dirt, leaves or insects on radiator or condenser
Hoses, Water pump, thermostat housing, radiator,
heater, core, plugs or head gasket leakage
Thermostat faulty
Incorrect ignition timing
Electric cooling system faulty
Radiator hose plugged or rotted
Water pump faulty
Radiator plugged or cap faulty
Cylinder head or block cracked or water passage
clogged
2. CHECK ENGINE COOLANT QUALITY
There should not be any excessive deposits of rust or scales
around the radiator cap or radiator filler hole, and the cool-
ant should be free from oil.
If excessively dirty, replace the coolant.
Check thermostat
Reset tinning
Inspect electric cooling system
Replace hose
Replace water pump
Check radiator and cap
Repair as necessary
TROUBLESHOOTING
CO±12, 13
IG±17, 20
CO±20, 22 Clean radiator or condenser
Repair as necessary Engine overheats
Possible causeRemedy Problem
CO±6, 9 Page
± COOLING SYSTEMCheck and Replacement of Engine CoolantCO±4
(d) To release the air, loosen the union bolt of the water out-
let five revolutions.
(e) Slowly fill the system with coolant.
Use a good brand of ethylene±glycol base coolant,
mixed according to the manufacturer's directions.
Capacity (w/ Heater):
M/T 9.5 liters (10.0 US qts, 8.4 Imp. qts)
A/T 9.4 liters (9.9 US qts, 8.3 Imp. qts)
(f) Tighten the union bolt of the water outlet.
Torque: 180 kg±cm (13 ft±Ib, 18 N±m)
(g) Install the radiator cap.
(h) Start the engine and check for leaks.
(i) Recheck the coolant level and refill as necessary.
HINT: When the coolant has been depleted, refill with
coolant and repeat steps (d) to (i). 4. (2VZ±FE)
REPLACE ENGINE COOLANT
(a) Remove the radiator cap.
CAUTION: To avoid the danger of being burned, do not re-
move it while the engine and radiator are still hot as fluid
and steam can be blown out under pressure.
(b) Drain the coolant from the radiator and engine drain cocks.
(Engine drain cocks are at the front center and rear right
of the cylinder block.)
(c) Close the drain cocks.
Torque (Engine drain cock):
300 kg±cm (22 ft±Ib, 29 N±m)
NOTICE:
wDo not use alcohol type coolant.
wThe coolant should be mixed with demineralized
water or distilled water.
Capacity (w/ Heater).
M/T 6.4 liters (6.8 US qts, 5.6 Imp. qts)
A/T (2WD) 6.3 liters (6.7 US qts, 5.5 Imp. qts)
A/T (4WD) 6.8 liters (7.2 US qts, 6.0 Imp. qts)
(e) Install the radiator cap.
(f) Start the engine and check for leaks.
(g) Recheck the coolant level and refill as necessary. (d) Fill the system with coolant.
Use a good brand of ethylene±glycol base coolant, mixed
according to the manufacturer's directions.
Using coolant which includes more than 5O%
ethylene±glycol (but less than 70%) is recommended.
± COOLING SYSTEMCheck and Replacement of Engine CoolantCO±5
REMOVAL OF WATER PUMP
1. DRAIN ENGINE COOLANT (See page CO±4)
2. DISCONNECT WATER TEMPERATURE SWITCH
CONNECTOR
3. DISCONNECT RADIATOR LOWER HOSE FROM
WATER INLET HOUSING
4. REMOVE TIMING BELT, PULLEYS
(See pages EM±23 to 26)
5. REMOVE WATER PUMP AND WATER PUMP COVER
ASSEMBLY .
(a) Remove the two nuts holding the pump to the water by±
pass pipe.
WATER PUMP (3S±FE)
COMPONENTS
± COOLING SYSTEMWater Pump (3S±FE)CO±6