02-16
2) Belt Tensioner
(1) Overview
The torque deviation from crankshaft affects the components in belt drive system and the belt
movement. The auto tensioner system is to adjust this deviation automatically.
In D20DTR engine, one of the mechanical tensioner, pivot damped tensioner is used to keep the
damping force, system reliability and durability. The single belt drive system needs to use the
automatic belt tensioning device to transfer the power to pulleys effectively. To get this, the
tensioner uses the spring and damping unit.
(2) Location
Belt tensioner
08-8
Oil filter module
Thermostat
When the engine coolant
reaches 90℃, the thermostat
starts to open (fully open at
100℃) and lets the coolant
flow to the radiator to
maintain the engine
temperature.
Water pump
The water pump is driven by the engine drive belt and
supplies the coolant to each area of the engine.
Coolant reservoir
Long life coolant is used.
1. SYSTEM DESCRIPTION
1) Overview
Water pump
Impeller vane Sealing
09-51451-01
2) Troubleshooting for Alternator
Item Cause Action
Overcharged
batteryDefective alternator voltage regulator
Replace the alternator
Defective voltage detection wiring Repair or replace
Loose alternator drive belt Adjust the belt tension or replace
Discharged batteryPoor connection of related circuit or
open circuitRetighten the loose connection or
repair open circuit
Defective alternator voltage regulator
Replace the alternator
Defective alternator voltage regulator
Replace the alternator
Terminated battery Replace the battery
Defective ground Repair
Charge warning
lamp does not
come on when
turning on ignition
switch with engine
stoppedDefective alternator voltage regulator
Replace the alternator
Open circuit in charge warning lamp,
fuse or wiringReplace or repair the charge
warning lamp or fuse
Defective ignition switch Replace the ignition switch
Defective ground of alternator circuit Repair
Charge warning
lamp is not turned
off after starting
engineDefective alternator voltage regulator
Replace the alternator
Corroded or worn battery cableRepair or replace the battery cable
Loose alternator drive belReplace the batteryAdjust the belt
tension or replace the belt
Defective wiring harness Repair or replace
04-6
2. DESCRIPTION AND OPERATION
1) General Description
The cooling system maintains the engine temperature at an efficient level during all engine
operating conditions.
When the engine is cold, the cooling system cools the engine slowly or not at all. This slow
cooling of the engine allows the engine to warm up quickly.
The cooling system includes a radiator and recovery subsystem, cooling fans, a thermostat and
housing, a water pump, and a water pump drive belt. The timing belt drives the water pump.
All components must function properly for the cooling system to operation. The water pump
draws the coolant from the radiator. The coolant then circulates through water jackets in the
engine block, the intake manifold, and the cylinder head. When the coolant reaches the operating
temperature of the thermostat, the thermostat opens. The coolant then goes back to the radiator
where it cools.
This system directs some coolant through the hoses to the heat core. This provides for heating
and defrosting.
The coolant reservoir is connected to the radiator to recover the coolant displaced by expansion
from the high temperatures. The coolant reservoir maintains the correct coolant level.
The cooling system for this vehicle has no radiator cap or filler neck. The coolant is added to the
cooling system through the coolant reservoir.
2) Radiator
This vehicle has a lightweight tube-and-fin aluminum radiator. Plastic tanks are mounted on the
upper and the lower sides of the radiator core.
On vehicles equipped with automatic transaxles, the transaxle fluid cooler lines run through the
radiator tank.
A radiator drain plug is on this radiator.
To drain the cooling system, open the drain plug.
3) Coolant Reservoir
The coolant reservoir is a transparent plastic reservoir, similar to the windshield washer reservoir.
The coolant reservoir is connected to the radiator by a hose and to the engine cooling system by
another hose.
As the vehicle is driven, the engine coolant heats and expands. The portion of the engine coolant
displaced by this expansion flows from the radiator and the engine into the coolant reservoir. The
air trapped in the radiator and the engine is degassed into the coolant reservoir.
When the engine stops, the engine coolant cools and contracts. The displaced engine coolant is
then drawn back into the radiator and the engine. This keeps the radiator filled with the coolant to
the desired level at all times and increases the cooling efficiency.
Maintain the coolant level between the MIN and MAX marks on the coolant reservoir when the
system is cold.
04-72112-01
4) Water Pump
The belt-driven centrifugal water pump consists of an impeller, a drive shaft, and a belt pulley.
The impeller is supported by a completely sealed bearing.
The water pump is serviced as an assembly and, therefore, cannot be disassembled.
5) Thermostat
A wax pellet-type thermostat controls the flow of the engine coolant through the engine cooling
system. The thermostat is mounted in the thermostat housing to the front of the cylinder head.
The thermostat stops the flow of the engine coolant from the engine to the radiator to provide
faster warm-up, and to regulate the coolant temperature. The thermostat remains closed while the
engine coolant is cold, preventing circulation of the engine coolant through the radiator. At this
point, the engine coolant is allowed to circulate only throughout the heater core to warm it quickly
and evenly.
As the engine warms, the thermostat opens. This allows the engine coolant to flow through the
radiator wherethe heat is dissipated. This opening and closing of the thermostat permits enough
engine coolant to enter the radiator to keep the engine within proper engine temperature operating
limits.
The wax pellet in the thermostat is hermetically sealed in a metal case. The wax element of the
thermostat expands when it is heated and contracts when it is cooled.
As the vehicle is driven and the engine warms, the engine coolant temperature increases. When
the engine coolant reaches a specified temperature, the wax pellet element in the thermostat
expands and exerts pressure against the metal case, forcing the valve open. This allows the
engine coolant to flow through the engine cooling system and cool the engine.
As the wax pellet cools, the contraction allows a spring to close the valve.
The thermostat begins to open at 82°C(180 °F) and is fully open at 95°C(203°F). The thermostat
closes at 80°C (176°F).
6) Electric Cooling Fan
Keep hands, tools, and clothing away from the engine cooling fans to help prevent personal
injury.
This fan is electric and can turn on even when the engine is not running. -
If a fan blade is bent or damaged in any way, no attempt should be made to repair or reuse
the damaged part. A bent or damaged fan assembly should always be replaced with a new
one to prevent possible injury. -
05-6
(2) Cold Cranking Amperage
The cold cranking amperage test is expressed at a battery temperature of -18°C(0°F).
The current rating is the minimum amperage, which must be maintained by the battery for 30
seconds at the specified temperature, while meeting a minimum voltage requirement of 7.2 volts.
This rating is a measure of cold cranking capacity.
The battery is not designed to last indefinitely. However, with proper care, the battery will provide
many years of service. If the battery tests well, but fails to perform satisfactorily in service for no
apparent reason, the following factors may point to the cause of the trouble:
Vehicle accessories are left on overnight.
Slow average driving speeds are used for short periods.
The vehicle's electrical load is more than the generator output, particularly with the addition of
aftermarket equipment.
Defects in the charging system, such as electrical shorts, a slipping generator belt, a faulty
generator, or a faulty voltage regulator.
Battery abuse, including failure to keep the battery cable terminals clean and tight or a loose
battery hold-down clamp.
Mechanical problems in the electrical system, such as shorted or pinched wires. ·
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·
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3) Charging Time Required
The time required to charge a battery will vary depending upon the following factors:
Size of Battery - A Completely discharged large heavy-duty battery required more than twice
the recharging time as a completely discharged small passenger car battery. ▶
<007b008c00940097008c00990088009b009c0099008c00470054004700680047009300960095008e008c00990047009b00900094008c0047009e00900093009300470089008c00470095008c008c008b008c008b0047009b00960047008a008f0088009900
8e008c00470088009500a0004700890088009b009b008c0099>y at -18°C(0°F) than at
27°C(80°F).
When a fast charger is connected to a cold battery, the current accepted by the battery will be
very low at first.
The battery will accept a higher current rate as the battery warms. ▶
Charger Capacity - A charger which can supply only 5 amperes will require a much longer
charging period than a charger that can supply 30 amperes or more. ▶
State-of-Charge - A completely discharged battery requires more than twice as much charge
as a onehalf charged battery.
Because the electrolyte is nearly pure water and a poor conductor in a completely discharged
battery, the current accepted by the battery is very low at first. Later, as the charging current
causes the electrolyte acid content to increase, the charging current will likewise increase. ▶
02-38710-01
1. PERFORMANCE AND SPECIFICATIONS
1) Rated Load & Input Signals
Rated Load ▶
NO. Item Rated Load
1 Chime bell / Buzzer DC 12V 350 mA (Inductive load)
2 Front room lamp DC 12V 16W (Lamp load)
3 Rear room lamp DC 12V 8W (Lamp load)
4 Ignition key illumination DC 12V 1.2W (Lamp load)
5 Seat belt indicator DC 12V 1.2W (Lamp load)
6 Parking brake warning lamp DC 12V 1.2W (Lamp load)
7 Door ajar warning lamp DC 12V 1.2W (Lamp load)
8 Door lock relay DC 12V 200 mA (Inductive load)
9 Door unlock relay DC 12V 200 mA (Inductive load)
10 Horn relay DC 12V 260 mA
11 Tail lamp relay DC 12V 200 mA (Inductive load)
12 Hazard warning lamp relay DC 12V 200 mA (Inductive load)
13 Power window relay DC 12V 200 mA (Inductive load)
14 Rear defogger relay DC 12V 200 mA (Inductive load)
15 Wiper LOW relay DC 12V 200 mA (Inductive load)
16 Wiper HIGH relay DC 12V 200 mA (Inductive load)
17 Front washer motor DC 12V 1.5A
18 Head lamp relay DC 12V 750 mA (Inductive load)
19 Front defogger relay DC 12V 200 mA (Inductive load)
20 Mirror lock relay DC 12V 200 mA (Inductive load)
21 Mirror unlock relay DC 12V 200 mA (Inductive load)
02-4
Input Signals ▶
NO. Input Signal Name Logic Status
1 IGN1 ON = BAT
(IGN ON or START)
2 IGN2 ON = BAT (IGN ON)
3 ALT_D ON = BAT (engine started)
4 Key reminder switch IN = BAT (key in)
5 Driver's door switch OPEN = GND, CLOSE = OPEN
6 Passenger's door switch OPEN = GND, CLOSE = OPEN
7 Rear door switch - OPEN (one of rear doors) = GND
- CLOSE (all rear doors) = OPEN
8 Hood switch OPEN = GND, CLOSE = OPEN
9 Driver's door lock/unlock switch LOCK = OPEN, UNLOCK = GND
10 Passenger's door lock/unlock switch LOCK = OPEN, UNLOCK = GND
11 Rear door lock/unlock switch - UNLOCK (one of rear doors)
= GND
- LOCK (all rear doors) = OPEN
12 Tailgate lock/unlock switch LOCK = OPEN, UNLOCK = GND
13 Rear defogger switch ON = GND, OFF = OPEN
14 Seat belt switch Unfastened = GND, Fastened = OPEN
15 Sunroof open switch ON = GND, OFF = OPEN
16 Parking brake switch ON = GND, OFF = OPEN
17 Air bag collision sensor ON = 200 ms output (LOW), OFF = OPEN
18 Wiper motor (parking) switch STOP = BAT VOLTAGE, ROTATING = GND
19 Washer switch ON = BAT, OFF = OPEN
20 INT-AUTO switch ON = BAT, OFF = OPEN
21 Auto washer switch ON = BAT, OFF = OPEN
22 Intermittent resistance 0W ~ 51KW (for intermittent wiper)
23 Speed sensor ON = GND (PWM), OFF = OPEN
24 Mirror lock/unlock switch ON = GND, OFF = OPEN
25 Front defogger switch ON = GND, OFF = OPEN
26 Auto hazard switch ON = GND, OFF = OPEN