Occurrence and effects of soot

Since combustion starts in diesel engines by injecting fuel into the the combustion chamber, there isn't enough time for air to mix with the fuel and because diesel fuel does not easily vaporize, it is difficult to mix with the air, causing pockets of concentrated of concentrated fuel. 

Because of this, parts have insufficient oxygen, causing incomplete combustion and generating soot (carbon). There is tendency for a large amount of soot to be generated when depressing the accelerator pedal heavily in particular, such as when starting or going up hills, as large amount of fuel is injected and pockets with insufficient oxygen are more likely to occur.

The ejected soot not only causes air pollution but also has adverse effects on the human body. Therefore, at the time of vehicle inspection, it is necessary to inspect whether the soot discharge is exceeding the standard or not.

This soot is not only ejected as exhaust gas, but is also absorbed into engine oil, degrading the oil. That's why engine oil for diesel engines contains many additives.

Additionally, if large amount of soot enters into the oil, wear of engine parts will accelerate and oil consumption will increase.

Therefore it is extremely important to inspect the oil on a daily basis.

Engine oil classifications for diesel engines

The diesel fuel contains sulfur and oil. Because of the sulfur content, sulfuric acid is generated through combustion.

This sulfuric acid is strong, corroding bearings, oxidizing oil and generating sludge. Therefore, diesel engine oil is required to have clean dispersiveness to prevent the generation of sludge and the ability to neutralize acid. Engine oil for diesel engines are classified into several standards, making it possible to know to which extent these performances are satisfied.

JASO classification

JASO is the Japanese Automotive Standards Organization. In Japan, API service classifications are commonly used as a quality standard for vehicle diesel engine oils, but due to design differences between Japanese and US engine, quality standards for engine oils more suitable to Japanese-made diesel engines were set.

There were newly set for vehicles equipped with post-treatment devices such as Diesel Particulate Filters (DPF) which complied with new short-term emission regulations, with DH-2 for trucks and buses, and DL-1 for passenger class vehicles.

 

Diesel engine description

Diesel engine are diesel fueled engines that are used in comparatively large vehicles, as they can produce a large amount of force at low speeds.

In addition, they have a good fuel economy and the fuel is cheap, making them economical and a popular choice for passenger cars as well.

In order to look at the characteristics of these diesel engines in detail, let's first compare gasoline engines and diesel engines.

The basic structure of both gasoline and diesel engines are almost the same, the combustion cycles are the same.  So what are the differences between gasoline and diesel engines ?

Let's look at each in detail.

• Differences in the combustion method
  In gasoline and diesel engines, the method with which fire is applied to burn the fuel is quite different.
  In gasoline engines, a spark ignites the fire.
  In diesel engines, the fuel burns through self-ignition.
  Self ignition is the same as pouring cooking oil into a pan, setting a fire under it, and leaving it.
  As the temperature of the oil rises, it self ignites and begins to burn. This is the biggest feature of diesel engines.
• Differences in the fuel used
  Diesel engines used for automobiles use diesel fuel, while gasoline engines use gasoline. Diesel fuel has a higher flash point than gasoline, as well as a lower ignition point. 
  In other word, gasoline will catch fire with a fire applied to it even at low temperatures, while diesel fuel will not at normal temperatures under the same conditions. The diesel fuel will be the first to ignite on its own when raising the temperature of the fuel itself.
  For this reason, ignition occurs in gasoline engines using spark plugs, while in diesel engines heat is applied to the diesel fuel directly for self-ignition.
  In diesel engines, heat is generated by compressing air. In self ignited diesel engines, it is necessary for the fuel to ignite easily, and so diesel fuel with good ignitability is convenient.

Handling engine oil

Be particularly careful of burns, etc., when handling (removing) oil that has been inside the engine, such as during oil replacement.

Also make sure to use safety glasses so that nothing gets in the eyes.

Take note of flames when handling oil as well as gasoline. Place removed oil into specified waste oil tanks, etc., and under no circumstances should it be poured down a drain, etc.

Removal and installation of radiator cap

• Make sure to apply a cloth to the cap, holding it lightly from above and turning it slowly approximately 90 deg in a counterclockwise direction.
• In this position, lightly shake the radiator cap in all directions. removing the pressure to the reservoir tank side.
• Confirm that the pressure has been released before removing the radiator cap.

Handling of long life coolant

• If long life coolant has been spilled around the radiator or reservoir tank while refilling, it will peel off the coated surfaces of parts, so make sure to rinse with water immediately.
• If any gets into your eyes, rinse immediately with large amounts of water.

Do not pour coolant down a drain, instead place it into a waste tank. (Tanks are separated differently for each store, and so the waste tank may be different form that for the waste oil, etc.)

Working safety

Gasoline is highly volatile, and when it comes into contact with the air it evaporates, becoming a combustible gas. Gasoline vapor is heavier than air, widely spreading across the ground, etc. Additionally, if there is a hole or pit, the gasoline tends to accumulate at the bottom of it. 

When handling gasoline, use safety glasses and make sure it does not come into contact with your eyes. Wash thoroughly if any makes contact with your skin.

Change immediately if gasoline comes into contact with your clothing. (As there is a danger of ignition or burning).

When disposing of cloth, etc. used to wipe up gasoline, pay attention to flames, etc.

Gasoline vapor is dangerous as it may ignite even from a small spark caused by static electricity or plugging in/unplugging an outlet, so make sure to pay attention to the following when handling.

• Eliminate any static electricity that may be stored in someone handling gasoline.
• When storing, always use a container with a lid, keeping it sealed.
• Keep in a well ventilated area where the temperatures are as low as possible.
• Do not use resin containers (plastic, etc.)

Since static electricity stored in gasoline can not escape, the danger of ignition increases. Additionally, even when using metal carrying cans, etc., placing them on insulated items such as cardboard will keep the static electricity contained in the gasoline and is dangerous.

• When transferring gasoline, do so gently to avoid generating static electricity.
• Do not transfer or remove using pumps for kerosene.
• Do not use gasoline drawn from a vehicle or excess gasoline for heaters, etc.

In the unlikely event of a fire, use an appropriate type of fire extinguisher. Applying water is dangerous, as it has the opposite effect of causing the gasoline to scatter, expanding the fire.

Fuel consumption

Fuel economy represents the distance (km) you can drive using one liter of fuel. There are various ways to measure fuel economy, but generally it is referred to as fuel consumption or fuel efficiency in catalogs, which is also known as mode fuel consumption.

Mode fuel consumption represents driving in a pattern (mode), combining stopping, acceleration, steady driving, deceleration and more.

There are various test methods depending on the country, including 10-15 mode and JC08 mode.

For example, company A may list fuel economy in urban areas in a catalogue. If company B lists suburban driving and company C lists highway driving, it won't be possible to compare them and see which company has the best fuel economy.

Therefore, fuel economy test methods (mode fuel consumption) are used by determining constant conditions for measuring fuel economy, so that we are able to compare fuel economy accurately.

Engine performance

Engine displacement

This is one value that shows the size of the engine, expressed in liters or cc. Generally, if this number is large, the engine itself is large and has a large output.

Number of cylinders

It is common for small vehicles to have 4 cylinders. 3 liter engines tend to have 6 or more cylinders.

Bore x stroke
This shows the cylinder diameter (bore) and the distance the piston can move (stroke). It is expressed in mm.

Maximum output

This shows the maximum output an engine is capable of. The output (kW) and the engine speed (RPM) that generates output are expressed together. Horsepower, PS is also sometimes included.

Maximum Torque

This shows the maximum torque an engine is capable of generating.

The torque (Nm) and the engine speed (RPM) which generates the required torque are expressed together. Torque (kgf/m) is also sometimes included.

Torque

Torque is a force that attempts to rotate around an axis.

For example, when tightening a bolt with a wrench, the rotational force applied to the bolt is the torque.

The strength of the force applied and the distance from the fulcrum to the point where the force is applied affects the torque. Therefore, even if applying the same amount of force, torque will increase if the distance between the fulcrum and the point where the force is being applied is increased and torque will decrease if the distance is shortened.

For engines, the torque expressed (Nm) is for a distance of 1 m. In the case of engines, this indicates how much force the crankshaft is rotating with using the power applied to the piston.

Engine output is expressed in kW.
As an example, let's imagine the different amounts of luggage the strong Mr. A and the weak Mr. B can carry. Because Mr. A is strong, he can carry two bags at a time. Mr. B isn't very strong, but he is fast, so he can only carry one bag at a time, but he can make two trips in the time it takes Mr. A to make one. This means that the amount of luggage each man can carry within a fixed amount of time is the same.

In this example, the amount of luggage that can be carried at one time is the engine torque (strength of the output force) and the number of bags that can be carried over a fixed period of time is the output (torque x revolutions). So in this, Mr. A and Mr. B have different torques, but their output is the same.

Output is also called "work rate". It's easy to understand if thinking about it in the terms of how many bags Mr. A and Mr. B carried (how much work they each did).

Coolant

Long life coolant

If the coolant in the radiator or cylinder block freezes, its volume increases, cracking the radiator, cylinder block, etc., and causing fatal damage to the engine.

Therefore, LLC is mixed with the water in the engine cooling system at a 30 to 50% ratio, lowering the freezing temperature as well as preventing overheating in the summer.

It also works to protect the cooling system from rust and corrosion using a high performance anti-corrosion formula.

Super long life coolant

This has approximately twice the life of normal LLC.

As a result it can reduce the amount of liquid wasted by replacement, making it friendly to the environment as well as a reduction in cost to the customer.

The color is pink compared to traditional LLC (red).

Conditions required for engine oil

Engine oil generally displays two items; the SAE (American Society of Automotive Engineers) viscosity classification and API (American Petroleum Institute) quality classification.

SAE viscosity classification
When the temperature of oil is high, its viscosity decreases (becoming free of stickiness, like water) and when the temperature is low it has greater viscosity (becoming sticky like honey).

With low viscosity there may be breaks in the oil film, making it easier for parts of the engine to seize.
Conversely, if this viscosity is high the resistance increases, making it more difficult to start the engine and increasing the amount of power loss.

The SAE viscosity classifications display oil viscosity using numbers, with a smaller viscosity number meaning an oil has less viscosity.
Those indicated as SAE20, SAE40, etc. are called single grade, and are usable in a narrow temperature range.
Those with a spread, such as SAE 10W-30 or SAE 20W-40, are called multigrade and can be used in a wide temperature range.
Currently, multi-grade engine oils are more commonly used for automobiles.

As an example, the "W" in 10W-30 stands for winter. Smaller number means, it is more difficult for the oil to harden at low temperature.
The "30" represents viscosity at 100 deg celcius. Higher number means the oil won't become too soft at high temperatures.

API quality classification (API service classification)
Since the oil is violently agitated at high temperatures, an environment is created where the oil can be oxidized easily by the oxygen in the air.
When the oil is oxidized, sludge (deposits of altered components), etc., are generated, decreasing lubrication performance.

In addition, most of the engine parts are made of metal and rust is prone to occur, so the oil is required to have high rust prevention performance as well as its quality should not change.

The API quality classifications are the most commonly used standard for oil quality. Since viscosity and quality required vary depending on the engine characteristics and use environment, it is essential to use oil with the specified standards.

The API quality classifications are separated based on quality and usage, determined by API test methods.

Gasoline and Oil

Various fluid such as fuel and lubricating oil are indispensable in operating the engine. Let's take a look at the characteristics of these oils in order.

Characteristics of gasoline

Octane number
The octane number is one value displaying the characteristics of gasoline, which is a numerical representation of its anti-knock properties.
The higher the number, the less likely knocking is to occur. Knocking is when the gasoline combusts abnormally in the cylinder, making a continuous sound as though a hammer were hitting the cylinder wall, lowering the engine output.
In worst case scenarios, the valve, piston, spark plug and more can be damaged. The octane number of gasoline generally sold does not differ greatly, with regular gasoline at about 90 and premium gasoline (unleaded high octane) at about 100, regardless of manufacturer.

Engine oil

The engine oil lubricates each part of the engine. There are various types of engine oil based on the engine characteristics and usage conditions, so it is necessary to check the appropriate oil to use.
The engine oil lubricates each part inside the engine. It also has various other important functions and properties.

Lubricating effect
Friction occurs on sliding surfaces, but it can be minimized if there is something that reduces friction on both surfaces. Lubricating oil makes an oil film on each sliding part inside the engine, lubricating and reducing friction between the sliding parts.

Cooling effect
There is a cooling system installed in the engine, but it is difficult for the cooling system to cool the pistons and sliding sections, and so when the lubricating oil circulates it takes away ambient heat and cools these areas.

Cleaning dispersion effect
Sludge and metallic dust are generated inside the engine due to combustion. If these accumulate in the sliding parts and oil passages, wear increases, oil passages become blocked, and lubrication failure occurs.
Lubricating oil therefore keeps these in the oil without depositing them in the engine.

Sealing effect
There is a gap between the piston and the cylinder which is sealed by a piston ring, but it can not be sealed completely.
Lubricating oil creates an oil film that improves the seal between the piston and cylinder, reducing the gas escaping through the gap.

Engine oil also has the following roles.

Anti corrosion effect
Makes it difficult for the oil film to be broken (anti-corrosion additives which act like a coating agent, tightly binding to iron, are added)

Oxidization neutralizing effect
Highly corrosive, acidic gases generated by combustion enter the oil and so the oil acts to neutralize this acid to protect metal parts from corrosion and wear.

Improved oxidation stability
Oil is oxidized as air enters it due to the heat from explosions, friction and churning.
Generally, the oxidation rate speeds up as the oil temperature increases, and so oxidation stability is improved by adding antioxidants.

(When oil becomes oxidized, oxidization degradation matter is formed, which spoil the oil's lubricative and clean dispersiveness properties)

Basic engine function

The fresh air and fuel drawn in through the air cleaner is combusted inside the engine, producing an explosion. This explosion provides a large amount of power.

This large amount of power pushes the piston down to turn the crankshaft, producing rotational power and turning the tires through the drivetrain.

4 cycle gasoline engine operation

Engine types include gasoline engines, diesel engines, and more. Now let's learn how the 4 cycle gasoline engine works, the most commonly used engine.

In the 4 stroke gasoline engine there are four cycle, from when the engine takes in the air-fuel mixture (the mixture of air and gasoline) until it discharges the exhaust gas.

Let's view the animation and see how each stroke works.

Intake stroke

The exhaust valve closes and the intake valve opens. As the piston drops the air-fuel mixture is sucked into the cylinder from the open intake valve.

Compression stroke

As the piston goes down BTDC, the intake valve closes. The air-fuel mixture drawn into the cylinder is compressed as the piston rises.

Combustion stroke

At the end of the piston's ascent, electricity flows to the spark plug, creating a spark which causes the compressed air-fuel mixture to combust and explode.
This explosive force pushes the piston down, rotating the crankshaft. It is power that drives the vehicle.

Exhaust stroke

As the piston finishes descending, the exhaust valve is opened, and as the piston rises it pushes the post-combustion exhaust gas out of the cylinder.

How the exhaust system works

The exhaust system is composed of an exhaust manifold, catalytic converter, muffler, etc. and purifies the exhaust gas discharged from the engine before releasing it into the atmosphere.
The muffler also suppresses the explosive sounds made during the release.

Catalytic converter
Exhaust gas contains toxic gases such as CO (carbon monoxide), HC (hydrocarbon) and NOX (nitrogen oxide). The catalytic converter is installed in the middle of the exhaust system and is a device for purifying this gas.

Muffler

Since the exhaust gas discharged from the engine is high temperature and high pressure, it emits an explosive sound if released directly.
Therefore the muffler lowers the pressure and temperature of the gas, suppressing the sound when discharging.

How to start the engine

As the engine can't be started under its own power, external force is required only for the initial " intake >> compression >> combustion >> exhaust" cycle, turning the engine.

The starter forcibly turns the crankshaft, causing an explosion by taking in the air fuel mixture and compressing it, starting the engine.

How the starter works
Generally a starter motor is used to start the engine.

Using the battery as the power supply, the starter motor turns the flywheel directly connected to the crankshaft, forcibly starting the engine.

This operation is performed from inside the vehicle using the ignition switch.

How the cooling system works

The engine becomes extremely hot during the combustion stroke. It is therefore necessary to keep the engine at an appropriate temperature (80 to 90 deg celcius with coolant temperature), so that the parts making up the engine do not become deformed by the heat, causing a serious malfunction.

Coolant temperature gauge
This is a gauge which measures the temperature of the coolant circulating inside the engine using a sensor, and informs the driver.
There are types where the light is blue if the engine coolant temperature is lower than it should be, and types where the light is red if it is higher than it should be.

Water pump

This is a pump that forcibly circulates coolant in the coolant circulation path. It is driven by the transmission of the crankshaft rotation through the belt and pulley.

Radiator
The radiator cools the coolant and it is composed of a radiator core, upper tank and lower tank. Coolant that has increased in temperature due to passing through the water jacket (a water channel set in the cylinder block and cylinder head) is sent to the radiator core, cooled, and then sent to the water jacket once again by the water pump.

Cooling fan

The radiator core is a mechanism that cools the coolant, using air sucked in by the cooling fan and the wind that enters from the vehicle being in motion.

Cooling fans are generally either the electric type which operates detecting the temperature of the coolant or a type that is driven by rotation from the crankshaft pulley and transmitted by the belt.

Reservoir tank

As the temperature of the coolant increases the volume of the coolant expands, overflowing from inside the radiator. The reservoir tank contains that overflowing coolant.

As the temperature of the coolant decreases, the coolant sent to the reservoir tank returns to the radiator, preventing the unnecessary outflow of coolant.

Thermostat
This is a device that adjusts the coolant temperature. The thermostat is located in the coolant path between the radiator and the engine and when the coolant in the engine is cold it stops coolant circulation to the radiator to prevent the engine from becoming too cold. Conversely, when the coolant temperature increases the coolant path is opened, sending coolant to the radiator and cooling the engine.

How the lubrication system works

There are many sections within the engine where friction occurs between parts in contact.
While driving  these areas of friction become extremely hot, which can cause seizure or parts to melt, which in turn can cause a serious accident.

For that reason it is necessary to reduce the frictional resistance by creating an oil film, making the rotating and sliding sections of the engine run smoothly. To accomplish this the lubrication system circulates oil for lubrication and continuously supplies oil to each part.

Oil pump
Pumps oil that has accumulated in the oil pan, applying pressure and sending the oil to the various parts of the engine.
Driven rotor - Drive rotor - Relief valve

Oil pressure warning light
This is a device that notifies the driver whether the oil pressure pumped to each part of the engine from the oil pump is normal or abnormal.
It is a mechanism that detects the state of the oil pressure using sensors installed in the oil passage.
The light is used to inform the driver when the oil pressure decreases. There is also an oil pressure gauge system that gives notification of this state using a needle.

Oil filter
The oil pumped by the oil pump is contaminated with foreign objects such as metallic dust that could not be removed by the oil strainer.
The oil filter removes these, protecting against wear and the engine seizing.
A relief valve is built into the integrated type filter, so that oil will pass if the element becomes clogged. For the element replacement type, only the internal elements can be replaced separately.

The integrated filter has a built-in relief valve that allows oil to pass through if the element becomes clogged. The check valve prevents foreign matter accumulated in the element from flowing back to the pump when the engine is stopped.

How the fuel system works

The fuel system supplies an amount of gasoline corresponding to the opening of the throttle valve to the cylinders, with impurities removed.

Fuel tank

A container for storing gasoline in the vehicle. It is installed in a position so that it cannot be damaged easily even if an accident were to occur.

Fuel injector

This is a device which injects the fuel into the intake manifold.

Fuel pump

This is a pump that sends gasoline from the fuel tank to the injector. The fuel pressurized by the pumps is regulated by the pressure regulator.

Fuel filter
Removes dirt and other impurities contained in gasoline using a filter element.

Fuel gauge

This is a device which measure the amount of gasoline remaining in the fuel tank using a sensor and informs the user.

How the intake system works

To obtain normal power from an air-fuel mixture explosion, it is necessary to mix the fuel and air at an appropriate ratio. The intake system is equipment that takes in air at this time. It is composed of an air cleaner, throttle valve, intake manifold etc.

Air cleaner

When outside air is sucked into the engine, this part cleans dirt and dust found in the outside air through use of an element.

Throttle valve

Linked with the operation of the accelerator pedal inside the cabin, this part adjusts the amount of air-fuel mixture sucked into the cylinder, according to the driving conditions.
When a large amount of power is required, the accelerator pedal is depressed by a large amount, increasing the air fuel mixture intake volume.

Main components of the engine

The engine is the most important part of a vehicle, in other words, it is its heart. For this reason it is composed piece by piece of particularly precise parts. Let's check and see what kinds of parts engines are composed of.

Cylinder block
This is the frame of the engine. A number of cylinders are arranged in the cylinder block, with the cylinder heads installed on the top surface and a gasket in between.

Piston
The pistons receive the pressure created by the combustion of the air fuel mixture and move vertically inside the cylinder. According to this vertical movement, pressure is transformed into movement, and that movement is transmitted to the crankshaft via the connecting rod.

Crankshaft
This changes the vertical movement of the piston (linear force) into rotational movement through a connecting rod.

Flywheel
This stores the power generated in the combustion stroke.
Of the four stroke in a 4 cycle gasoline engine, force is generated only in the combustion stroke, with the other three strokes operating by using the force generated in the combustion stroke.
For this reason, the flywheel is made of a heavy disc, so that the rotational force from the crankshaft can be converted into an inertial force and stored.

Cylinder head
Located above the cylinder block, the depression on its underside forms the combustion chamber with the cylinder.

The combustion chamber is the gap between the piston, cylinder block and cylinder head where the air-fuel mixture is take in, compressed and made to combust.

Operating valve mechanism
The cylinder heads of a 4-cycle engines are equipped with an intake valve and exhaust valve. The air-fuel mixture is introduced into the cylinder and combustion gas is emitted outside the engine.
The series of devices that open and close this valve at the appropriate intervals is called the operating valve mechanism.
Two rotations of the crankshaft (2 full motions of the piston) rotate the camshaft 1 time (each valve opens and closes once)

Oil pan
A section for collecting the engine oil, where one section is deeply dented and an internal partition is attached, so that even if the vehicle is at angle a sufficient amount of oil can be collected in the bottom of the oil pan.

Basic Engine Structure

Engines are classified by the type of fuel they use, such as gasoline or diesel but there are also several shapes of engines.

Inline type

The cylinders are arranged in a single row allowing for a simple structure. As the number of cylinders increases, the overall length of the engine increases as well.

V type

In a V type engine, the cylinders are arranged with the crank in between, allowing the engine body to be shorter than an inline engine with the same numbers of cylinders.

Additionally, since the shape of the block is close to cube, rigidity of the engine can be increased. The angle of the V (bank angle) can be 60 deg, 72 deg, 90 deg, etc.

On the other hand, the complexity of the structure increases as the number of parts increases as the number of parts increases.

Horizontally opposed

In addition to having a low center of gravity and a short overall length, the horizontally opposed pistons move in opposite directions to the left and right, cancelling each other force and resulting in smooth operating and low vibration.

Due to this it is having a low center of gravity compared to inline engines and make it stable.

Various equipment other than the engine are required to operate the engine. Now let's take a look at the structure of the engine and the various equipment needed to operate the engine.

Vehicle power

The role of engines

Vehicles themselves are heavy and in order to run while carrying people and heavy objects, significant power is required.

The component that generates this power is the engine. Also, since vehicle must run on various kinds of roads, such as hills and highways, it is necessary for the driver to be able to freely control the power generated by engine.

As an engine runs it continuous to heat up. It felt like this it would break down due to heat. In order for the engine to be run for long periods of time, there is a cooling system.

Power from the engine is also used to operate devices such as the air conditioning.

As such, the engine plays an important role in powering the vehicle. Let's take a look at the different types of engines and power not from engine.

Gasoline engine

Gasoline engine are small, lightweight, have high output and because they make little noise or vibration, they are used in the passenger vehicles, so much so that the gasoline engine is near synonymous when speaking of engines for passenger cars.

Diesel engine

Vehicles equipped with an engine that uses diesel as fuel. Diesel engines are economical as fuel costs are low and they have good fuel efficiency, but they are inferior to gasoline engines when it comes to vibration, noise, acceleration etc.

Hybrid

Vehicle powered by both an engine and an electric motor.

By driving using the efficient points of both the engine and motor, fuel economy and acceleration performance are improved.

Electric vehicle
One characteristic of these is that no exhaust gases are put out, as the vehicle runs only with a motor. On the other hand, a large battery is required, it has a low traveling range compared to gasoline engines, and it takes time to charge the battery.

Fuel cell vehicle

Using hydrogen as fuel, electricity is drawn using a chemical reaction, and the vehicle runs by turning a motor.

It is an environment friendly vehicle that discharges only water. On the other hand the safe handling of hydrogen and few fueling system stations still present a problem.

Toyota Customer Service Basic

Toyota customer service basic principles

Earn the trust of both customers and society by providing appealing products together with outstanding service.

1. Ensure customers' needs and expectations (quality, price, speed) are always met and strive to enhance service provision to ensure accurate, caring service that will satisfy customers and earn their trust.

2. Quickly and accurately grasp field information and contribute to making even higher quality vehicles and products.

3. Conduct business in a fair and honest manner to earn the trust of all stakeholders and society as a whole.

4. Maximize the potential of both individuals and the organization to create a culture rich in creativity and vitality.

5. Build strong bonds with all customers and develop efficient operations to sustain consistent growth of both sales and service.

Toyota 3S Philosophy 7 Basic Actions

In 1973, as one of the pillars of the "Toyota Service 3S Campaign", the "Basic 5 Actions" was established as a standard of conduct for Toyota Service.
This was revised to the "Basic 7 Actions" the following year. All service staff renewed their commitment to the company principles inherited from the time of its founding, and aimed to restructure the basics of service operations to earn the trust of customers.

In 2025, revisions were made to the principles to adapt to changes in the times and environment, with a focus on the customer. At the same time, the names was changed to "Toyota 3S Philosophy 7 Basic Actions" with the addition of the premise that "Safety, Compliance and Quality are the top priority" as the code of conduct.

The 7 Basic actions demonstrate the 3S Philosophy as concrete actions, and have been positioned as a code of conduct for service activities.
This is the basis for making all decisions and actions. First, prepare a safe working environment then comply with laws, social norms and business ethics. Lastly but not least, ensure the quality of service (maintenance, technical skills, and communication with customers).
Only when the precondition is fulfilled can we carry out our operations and build trust with our customers.

1. Always greet each and every customer and coworker
A greeting is an action that makes the other person feel welcomed. All staff members should greet customers with heartfelt appreciation and sense of welcome. Additionally, greetings are important for communication among staff, which is essential for teamwork and it is important to express gratitude towards one another.

2. Maintain your appearance for a positive impression
We interact with a wide range of customers, including those of different genders, occupations, and age groups. Let's make an effort to maintain a neat appearance that leaves a good impression on all customers. Additionally, it's important to pay attention to our prompt responses and posture as well.

3. Listen attentively, look carefully and communicate actively.
The foundation of communication is to respect and acknowledge the other person and it is important to have an attitude of listening attentively to customers. Especially when asking about a malfunction to the customer, we should check with the vehicle and ask specific questions about the situation.

4. Handle customers' vehicles with the utmost care
Taking good care of customers' vehicles is the same as taking good care of our customers. We should handle all vehicles with care and caution. Additionally we should not only be mindful of keeping our own clothes clean but also use clean covers for seat covers and fender covers to show our consideration for the customers' vehicles.

5. Always check the quality after the work is completed
Let's ensure that the customers' requests are being carried out properly and that the work is being completed appropriately. It is important to accurately record the results of the work and explain them clearly to the customer so they can understand and appreciate the value of the inspection and maintenance service. Additionally we should check to see if any tools or equipment have been left behind in the vehicle and ensure that both the interior and exterior are clean.

6. Explain the work performed to the customers in an easy to understand manner
To ensure that customers can use their vehicles with peace of mind, it is necessary for them to recognize the inspection and maintenance service and understand its details. To achieve this, we should avoid technical terms and instead use general terms that are appropriate for the customer. By providing clear explanations tailored to diverse customers, we can build trust with them.

7. Perform post service follow up and confirm customer satisfaction
About a week after the maintenance, we should express our gratitude to customers who have brough in their vehicles, as well as confirm the results of our work and that any problems have been resolved.
In same cases, we may receive complaints or criticism. However simply repairing the vehicle again is not enough. It is necessary for us to deeply reflect on where our process may have gone wrong and to turn the customer's dissatisfaction into satisfaction.

Toyota Customer Service 3S Philosophy

Seikaku (Accuracy) + Shinsetsu (Caring) = Shinrai (Trust)

This philosophy was developed in the 1976s, at the time when Japan was experiencing rapid motorization and was in the midst of so called sellers market. It was also a time when a thorough awareness of customer first had not yet become established.

Given this situation, we realized, we realized we needed to return to our roots and carefully review our approach to customer service. This led to the creation of our customer service philosophy, the pillar that supports all personnel engaged in customer service.
3S philosophy emphasize the accurate work with caring attitude will build strong trust among our customers. 

The Origin of Customer Service

Introduction

We hope that all of you will become the key person of future auto-technician service by enhancing technical capabilities, studying the origin of customer service and passing it down the generations.

Let us understand the story of repair following the breakdown of G1 truck during initial days of company operation that led to the origin of customer service.
During initial days of company formation, many vehicle break-drowns were reported and also lot of trouble occurred to customer.
In those days, auto-technician personnel's used to rush to the customers location to earn back the trust of the customer and improve vehicle quality. 

Sincere, wholehearted response were made to minimize the inconvenience to the customer in unfortunate situation.

With priority on preventing further inconvenience to the customer, auto-technician staff used to offer an American made truck (known for its reliability) as a temporary substitute for the broken-down vehicle.
Since continuous sincere efforts are rooted in the customer first philosophy and to demonstrate this philosophy, the staff used to rush to the customer location, apologize and transfer the cargo to the temporary replacement vehicle.
Such honest and sincere efforts made it possible to earn back the trust of the customer and till today these sincere efforts are remembered and also represent the foundation of Customer Service today. 

Dealer and manufacturing staff work together as a team using the Genchi Genbutsu approach to determine the cause of the breakdown.

In addition to dealer staff, technicians from the vehicle manufacturer used to rush to the customer location and utilize genchi genbutsu approach to accurately analyze the situation and make an logical guess as to the cause of the breakdown.
These efforts facilitate speedier correction of the original problem later at the manufacturers facility as well as improved the vehicle quality and also enhanced the dealer-manufacturer relationship.
Sense of direct involvement and responsibility going beyond the assigned company roles and position.

At the time of vehicle breakdown at the customer location, Kiichiro Toyoda refuses to leave all responsibility to the auto-technicians and rushes to the problem location. Always demonstrated the genchi genbutsu spirit as a company leader.
Kiichiro Toyoda often used to crawl down underneath the vehicle, dirtying his clothes and always used to check from his eyes.

The sense of personal, direct responsibility and involvement going beyond the roles and position within the company.
These demonstration proved the core values of  Toyota like Customer First, Genchi Genbutsu and Quality First.

Strong passion and the commitment of the people demonstrated during the initial days of company operation are consolidated as the values and philosophies which are being practiced till today.