Is it legal to change from 17-inch to 18-inch wheels?

What Causes a Car Air Conditioner to Alternate Between Hot and Cold?

Car air conditioners alternating between hot and cold are caused by the tripping of the compressor's protection device. Below are specific explanations regarding the compressor's protection device: 1. Exhaust Temperature: Excessive exhaust temperature leads to refrigerant decomposition, aging of insulation materials, carbonization of lubricating oil, valve damage, and capillary tube blockage. The primary protection method involves using a temperature controller to sense the exhaust temperature. The temperature controller should be placed near the exhaust port. When the exhaust temperature is too high, the temperature controller activates, cutting off the circuit. If the high exhaust temperature is caused by hot gas bypass, shutting down the system should not be the solution; instead, liquid injection cooling should be applied. 2. Shell Temperature: Excessive shell temperature may result from insufficient heat exchange capacity of the condenser. Therefore, it is necessary to check the condenser's air or water flow, whether the water temperature is appropriate, and whether air or other non-condensable gases have entered the refrigeration system. If the condenser pressure rises, the shell will overheat. High suction temperature also causes the shell to overheat. Additionally, motor overheating can lead to shell overheating.

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What is the deployment speed of an airbag?

Here is the relevant introduction about the deployment speed of an airbag: 1. The airbag deployment requires a relative speed greater than 50km/h, and the acceleration in the opposite direction at the moment of collision must exceed 40g. In other words, the relative speed must be >50km/h, and the impact force must meet the conditions for this speed to occur. Different automakers have varying settings for the airbag deployment conditions. The airbag will only deploy if the impact point is near the sensors, typically within a 60° angle in front of the vehicle. Side airbag/curtain sensors are located near the doors. The airbag will deploy only when colliding with rigid walls or obstacles. Hitting the sensor location with hard objects like a hammer will not trigger the airbag, as the sensor activation is primarily caused by speed. 2. The controller relies on three acceleration sensors (not speed sensors) to send the deployment command to the airbag. Therefore, even at high speeds, the airbag will not deploy if the acceleration value (corresponding to the impact force) during the collision does not exceed the set threshold. Similarly, even at lower speeds, the controller will issue the airbag deployment command if the acceleration value during the collision exceeds the set threshold.

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What is the purpose of adding urea to a car?

Adding urea to a car primarily serves the purpose of purifying exhaust emissions in the vehicle. The technical name for automotive urea is Diesel Exhaust Fluid (DEF), which is used in diesel engines. It reacts with nitrogen oxides (NOx) in the exhaust, reducing NOx emissions while also optimizing engine performance and fuel consumption. More detailed information is as follows: 1. Purpose of adding urea: Urea is specifically for diesel engines, as they emit harmful nitrogen oxide gases during operation. These gases are detrimental to both the atmosphere and human health, with long-term exposure leading to respiratory diseases. To mitigate these hazards, urea is employed. This involves a catalytic reaction where urea interacts with the nitrogen oxides emitted by diesel engines, triggering a chemical reaction that converts the nitrogen oxides into harmless nitrogen and water vapor, both of which are benign to the atmosphere and human health. 2. Automotive urea, technically known as Diesel Exhaust Fluid: It is an essential consumable in Selective Catalytic Reduction (SCR) technology. The SCR system includes a urea tank and an SCR catalytic converter. The SCR system operates as follows: when nitrogen oxides are detected in the exhaust pipe, the urea tank automatically sprays Diesel Exhaust Fluid. The fluid then undergoes a redox reaction with the nitrogen oxides in the SCR catalytic converter, producing non-polluting nitrogen and water vapor that are safely expelled. 3. Consequences: Failure to use Diesel Exhaust Fluid, or using fluid of insufficient purity or inferior quality, can result in automatic engine deceleration. Additionally, substandard Diesel Exhaust Fluid can contaminate the catalyst in the SCR catalytic converter, leading to severe consequences.

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What documents are required for the Subject 1 test?

For the test, you only need to bring your ID card. The admission ticket and other documents are handled by the driving school, which will distribute them during the test. Electronic IDs cannot be used for the test. If you don’t have an ID card, you can apply for a temporary ID card, which has the same validity as a regular ID card. According to the "Regulations on the Application and Use of Motor Vehicle Driver's Licenses," the Subject 1 test can be taken twice on the same day. If you fail the first attempt, you can take a free second attempt. If you fail the second attempt, the Subject 1 test will be terminated, and you can only reschedule the test after ten days. The Subject 1 test consists of 100 questions, including single-choice and true/false questions, with each question worth 1 point and a total score of 100. If you answer 11 questions incorrectly during the test, the system will automatically submit the test and end the exam. The Subject 1 test is computer-based and lasts 45 minutes. Subject 1 test content: Regulations on driver's licenses and motor vehicle management; road traffic conditions and regulations; traffic safety violations and penalties; regulations on road traffic accident handling; basic knowledge of motor vehicles; local regulations; knowledge of braking systems and safety devices for large and medium-sized passenger and freight vehicles; specialized knowledge for wheeled self-propelled machinery, trams, and trolleybuses. Subject 1 test precautions: Candidates should pay attention to their attire and are not allowed to wear slippers. Electronic devices and bags are not permitted in the test room. Bring your ID card and queue to enter the waiting hall. Observe the precautions and procedures on the large screen, and store personal belongings in the lockers before entering the test room. After entering the test room, the identity verification station will assign a seat. Once seated, begin the test. Ensure the camera is aligned with you and follow test discipline. If you fail the first attempt, you can retake the test on the same day. If you fail again, you must pay to reschedule. After the test, queue to collect your score report and sign it. Failure to sign will render the test invalid. There is no limit to the number of times you can schedule the Subject 1 test. Each subject can be taken once, and if you fail, you can retake it once. If you do not take the retest or fail the retest, the test will be terminated, and you must reschedule. For Subject 2 and Subject 3, there are only five attempts. Subject 2 and Subject 3 tests can be rescheduled after ten days. If you fail the Subject 3 safe driving knowledge test, the previously passed road driving skills test results remain valid. There are three subjects in the driving test: Subject 1, Subject 2, and Subject 3. Subject 1 refers to the test on road traffic safety laws, regulations, and related knowledge. Subject 2 refers to the field driving skills test. Subject 3 is divided into two parts: road driving skills and safe driving knowledge. The safe driving knowledge test is conducted after Subject 3, so it is commonly referred to as Subject 4. However, in official terms (i.e., the Ministry of Public Security’s Order No. 123), there is no such thing as Subject 4.

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What are the precautions for using ETC?

ETC stands for Electronic-Toll-Collection, which means electronic toll collection system. ETC can be applied for at bank outlets or highway service areas. The original and photocopies of the vehicle owner's valid ID card and vehicle license are required. If it is not the owner who applies, the agent's valid ID card is also needed. The photocopy of the vehicle license should include the page with the most recent annual inspection seal. A bank card for deducting highway tolls is also required. The applicant must be between 18 and 60 years old, and the vehicle must be registered under an individual's name. About the installation precautions for ETC: Do not block the view; it is best to install it behind the rearview mirror: Many car models have a large inclination angle of the windshield, which reduces the driver's field of vision. If this is not considered when installing ETC, it will increase the driver's blind spot. Install it on the right side behind the rearview mirror to avoid blocking the view. Do not affect charging: The ETC electronic tag consumes power, but generally does not need to be charged or have its battery replaced because it has a solar panel on the back that can charge itself. Therefore, when installing, avoid the black areas on the windshield and do not place it where the solar panel might be blocked. Once installed, do not remove it casually: The button in the middle of the adhesive is an anti-removal lever, connected to a switch below. After the electronic tag is installed, the windshield will press the anti-removal lever in. If it is removed casually, the lever will pop out and trigger the switch, locking the electronic tag and making it unusable. You will then need to go to an ETC service point to unlock it. This is designed to prevent multiple vehicles from sharing one device. Precautions for using ETC: The ETC transaction sensing area is 8 meters. To prevent the ETC device of the vehicle in front from malfunctioning, keep a distance of more than 10 meters from the vehicle in front to avoid automatic sensing and paying for the vehicle in front. The ETC lane recognizes a speed of 20 kilometers per hour. If the speed is too fast, the vehicle's device information cannot be read, leading to a failed toll deduction. When using a debit card linked to ETC, insufficient balance will also cause the toll deduction to fail. Precautions for using the ETC card: Before using ETC to pass through a toll station, ensure that the ETC card is correctly inserted into the OBU. The ETC card may become loose due to bumps during driving, so it should be checked and reinserted into the OBU promptly if it becomes loose. The ETC card must be dedicated to one vehicle and cannot be changed arbitrarily after being bound to the vehicle. Before using ETC, check the fee information displayed on the dedicated lane sign. If the card balance is insufficient, recharge it promptly. When the car passes through the ETC lane and the barrier does not lift, follow the instructions of the toll station staff or switch to the manual toll lane. If the ETC toll lane at the highway toll station is temporarily closed, use the manual toll lane for payment. The speed limit for the ETC lane is 20 kilometers per hour, and a distance of more than 5 meters should be maintained from the vehicle in front before passing through. If an ETC vehicle receives a toll card in the manual toll lane, it cannot use the ETC toll lane when exiting the highway and must use the manual toll lane instead.

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What kind of car can be passed down through three generations and still running when the owner is gone?

A car that can be passed down through three generations and still running when the owner is gone includes the following models: 1. Toyota Corolla: This car has always had excellent sales in the Chinese market. Its outstanding sales performance is attributed to its stylish exterior design, impressive vehicle configurations, excellent fuel efficiency, and reliable quality. Some owners even commented that apart from refueling, there are virtually no additional maintenance costs, highlighting its strong reputation among consumers. 2. Honda Fit: Many people consider this car to have outstanding performance and great potential for modifications. However, its build quality is also top-notch, with very few major issues reported. Although its configurations are relatively basic, its reliability ensures a solid performance in the market. Additionally, the car offers significant modification potential, earning it the nickname 'financial product' in the automotive world. Even today, many older-generation Fits can still be seen on the roads. 3. Wuling Series: Despite its affordable price, Wuling maintains high-quality standards. Whether used for transporting goods or driving to Tibet, Wuling vehicles rarely encounter problems.

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Is it legal to change from 17-inch to 18-inch wheels?

What Causes a Car Air Conditioner to Alternate Between Hot and Cold?

What is the deployment speed of an airbag?

What is the purpose of adding urea to a car?

What documents are required for the Subject 1 test?

What are the precautions for using ETC?

What kind of car can be passed down through three generations and still running when the owner is gone?

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