What are the contents of Subjects 1, 2, 3, and 4 respectively?

How Long is the Paint Warranty at a 4S Shop?

At a 4S shop, the paint warranty period is generally at least 1 year or more. It is recommended to first consult the service station to check the warranty duration. Non-manufactured scratches can be covered under warranty. Below is a supplementary introduction to the 4S shop paint process: 1. Body sheet metal/paint surface grinding. After scratches or collisions, sheet metal repair is usually needed to restore the basic shape. Professional paint grinding tools are used to remove the original paint, exposing the metal panel. 2. "Putty application" for leveling. Putty is mainly used to ensure the paint surface is smooth and to fill in depressions. Generally, it needs to be applied 3 times, which affects the final paint result. 3. Use a paint scanner to match the car paint, followed by manual fine-tuning. Due to varying usage periods of different vehicles, the paint may have slight changes. Technicians need to compare the paint sample with the body color on-site. Fine-tuning tests the technician's experience and is the most crucial step. 4. Paint application. The types of paint mainly include standard paint, metallic paint, and pearl paint. Prices vary depending on the type and brand of car paint.

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How much battery does a Tesla normally lose overnight?

The BMW 730 should use 95-octane gasoline, as this fuel grade is recommended in the vehicle's official user manual. In addition to checking the appropriate fuel grade in the user manual, the BMW 730's fuel cap also indicates the recommended gasoline type. Generally, the fuel grade can also be determined based on the engine's compression ratio. Vehicles with a compression ratio between 8.6-9.9 should use 92-octane gasoline, while those with a compression ratio between 10.0-11.5 should use 95-octane gasoline. Higher compression ratios may require 98-octane gasoline. However, with the use of new technologies, the compression ratio alone cannot determine the appropriate fuel grade, as high-compression engines can also be tuned to use lower-octane gasoline. Other factors, such as ignition timing, turbocharging technology, and Atkinson cycle technology, also play a role. Generally, the higher the fuel grade, the higher the octane rating and the better the anti-knock performance. 92-octane gasoline contains 92% isooctane and 8% n-heptane, while 95-octane gasoline contains 95% isooctane and 5% n-heptane. If the BMW 730 occasionally uses the wrong fuel grade, simply switch back to the correct grade after the tank is empty. However, prolonged use of the wrong fuel grade can have the following effects: Using a higher-octane fuel in a vehicle designed for lower octane will not cause damage, but the increased octane rating can alter the fuel's ignition point, leading to delayed combustion in the engine. This reduces the engine's power output and thermal efficiency, resulting in poorer performance. Using a lower-octane fuel in a vehicle designed for higher octane can cause engine knocking. The significantly lower octane rating lowers the fuel's ignition point, causing premature ignition during the compression stroke. If combustion occurs before the spark plug fires, resistance is created during the upward stroke. This resistance makes the engine run very unevenly. Mild knocking may only increase noise without significant engine damage, but severe knocking indicates serious engine issues, affecting not only driving stability but also causing abnormal wear on pistons and cylinders, potentially leading to cylinder scoring.

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What are the consequences of not scrapping a motor vehicle when it expires?

If a car has reached its scrapping period but has not been scrapped, it will affect the renewal of the driver's license or annual inspection. Driving a car that has not undergone the annual inspection may result in a fine ranging from 200 to 2000 yuan, revocation of the driver's license, and mandatory scrapping of the car, with all costs borne by the owner. More information on vehicle scrapping is as follows: 1. Consequences: If an accident occurs while driving a scrapped vehicle, even if the other party is largely at fault, the owner will still be required to bear the compulsory traffic insurance compensation limit, with a maximum compensation of 122,000 yuan. More seriously, if the accident causes serious injury to one person, the owner will be held primarily responsible and may face criminal charges. Driving a scrapped vehicle is an aggravating circumstance, and probation is generally not granted. 2. Cannot be sold as scrap: Additionally, if the owner sells the car as scrap, some illegal elements may retain the vehicle's identification marks such as the engine number and chassis number and install them on other vehicles. Once such a modified vehicle is involved in an accident, authorities can trace it back to the original owner through these identification marks, which will inevitably lead to trouble and unnecessary losses for the original owner.

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Can water be used as coolant?

Temporarily unable to find the same type of coolant? A small amount of purified water can be used as a substitute. Coolant consists of three components: water, antifreeze, and additives. It circulates in the engine cooling system, carrying away excess heat generated during engine operation to ensure the engine operates at normal working temperature. The functions of coolant include the following four points: 1. Winter antifreeze: To prevent the coolant from freezing after the car is parked in winter, which could cause the radiator and engine block to crack, the freezing point of the coolant should be about 10°C lower than the lowest temperature in the region to prepare for sudden weather changes; 2. Anti-corrosion: The radiator, water pump, cylinder block, cylinder head, water distribution pipe, and other components in the cooling system are made of steel, cast iron, brass, copper, aluminum, solder, and other metals. Due to the different electrode potentials of different metals, electrochemical corrosion can easily occur under the action of electrolytes. At the same time, the acidic products formed after the decomposition of glycol substances in the coolant and the acidic exhaust gas after fuel combustion may also penetrate into the cooling system, promoting corrosion of the cooling system; 3. Anti-scaling: The coolant should minimize the formation of scale during circulation to avoid clogging the circulation pipes and affecting the heat dissipation function of the cooling system; 4. Anti-boiling: The boiling point of coolant is usually over 105°C, compared to the boiling point of water at 100°C. Coolant can withstand higher temperatures without boiling (overheating), meeting the cooling needs of high-load engines to a certain extent.

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Where Are the Airbag Locations?

Airbag locations include the outer side of the seat; the side near the window on the rear car seat; the area below the steering wheel in the front row; and the inner side of the windshield beam. Airbags are classified as follows: 1. Single airbag, dual airbags: In mid-to-low-end cars, the standard number of airbags is 1-2, typically one each for the driver and front passenger positions, providing effective protection for the chest and head of front-seat occupants in the event of a collision. 2. Four airbags: In mid-range B-segment cars, there are usually four airbags—two for the driver and front passenger positions, and two inside the side doors. These effectively cushion impacts from the front and sides. 3. Multiple airbags: In high-end cars, airbags are located in the front driver and passenger positions, with two on each side of the front and rear doors, and 18 curtain airbags distributed around the front and rear windshields and side windows, providing comprehensive protection. 4. Airbag seat belts: These feature airbag devices in the shoulder and entire length of the seat belt, combining the characteristics of traditional seat belts and airbags to offer collision protection for passengers. 5. Side airbags: Installed on the outer side of the seat to mitigate injury. 6. Knee airbags: Designed to reduce injuries to the knees from interior components during secondary collisions. Located inside the front driver's seat, they effectively protect the lower limbs of passengers and help absorb forward impact. 7. Head airbags: Primarily aimed at protecting the heads of passengers.

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Does the antifreeze in the car radiator need to be replaced?

The antifreeze in the car radiator needs to be replaced periodically. For vehicles that run for long periods, such as taxis, high-quality antifreeze should generally be replaced once a year. For vehicles with shorter running times, it can be replaced every two years or every 30,000 kilometers. To prevent excessive foaming, which reduces the heat exchange efficiency between the antifreeze and engine components, ensure the product is within its validity period when adding it. Long-life antifreeze can last up to three years. If suspended particles, sediment, or signs of deterioration or discoloration are found in the antifreeze, it should be replaced promptly, and the system should be cleaned. The method for replacing antifreeze is as follows: Before completely replacing the antifreeze, conduct a thorough inspection to check for any leaks or cracks in the pipelines, with a focus on the five-way hose. Antifreeze flows through the five-way hose and is distributed to different parts of the car to function. If there are signs of antifreeze leakage in this section, replace the hose or reseal the connection as needed. Drain the old antifreeze, then flush the fluid channels with clean water. Add clean water to the antifreeze reservoir and continue filling until water flows continuously through the engine cooling system. Then, start the engine and let it idle for 3 to 5 minutes to circulate the water. Initially, the water flowing out of the reservoir may have a faint pink tint. Continue adding clean water until the outflow is clear. Note: Do not forget to remove the heater hose and drain the water from the heater core. After draining for about an hour, add the new antifreeze through the radiator hose. Then, pour another container of antifreeze into the antifreeze reservoir until it is nearly full. Start the engine and let it run for about 10 minutes. As some air is expelled from the cooling system, the fluid level will drop. Add more antifreeze until it reaches the "MAXT" mark on the reservoir.

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What are the contents of Subjects 1, 2, 3, and 4 respectively?

How Long is the Paint Warranty at a 4S Shop?

How much battery does a Tesla normally lose overnight?

What are the consequences of not scrapping a motor vehicle when it expires?

Can water be used as coolant?

Where Are the Airbag Locations?

Does the antifreeze in the car radiator need to be replaced?

Where is the rearview mirror heating button on the Changan CS55?

What does EV mean?

How to Check Your Vehicle's Emission Standard?

Is it okay to use LED headlights without lenses?