What are the main functions of an engine lubrication system?

Do I still need to display the 2021 vehicle inspection sticker?

In 2021, it is no longer necessary to display the annual vehicle inspection sticker, as vehicles are not required to show any physical stickers since that year. Starting from June 2020, China has implemented the digitalization of annual inspection stickers nationwide. Now when vehicle owners complete their annual inspection, they will not receive a paper inspection sticker. Instead, owners can directly obtain the electronic inspection sticker through the 12123 traffic management app. For owners who have obtained the electronic inspection sticker, it holds the same validity as the paper version. During traffic police checks, presenting the electronic inspection sticker is sufficient. For vehicles under 6 years old, owners need to apply for the annual inspection sticker every two years at the vehicle management office, though online application is also an option. For vehicles older than 6 years but less than 10 years, the inspection frequency has been relaxed from annual to biennial checks. This means only two on-site inspections are required within 10 years - at the 6th and 8th year marks, effective from November 20, 2020. Vehicles over 10 years old continue with annual inspections. As for vehicles older than 15 years, semi-annual inspections are mandatory to ensure roadworthiness.

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Does touching the line with the car head in the S-curve of Subject 2 result in point deduction?

Touching the line means the vehicle body crosses the line. In the Subject 2 exam, if the vehicle body crosses the line, 100 points will be deducted, resulting in a failed exam. In addition to the vehicle body crossing the line, other actions that will deduct 100 points include failing to enter the garage during reverse parking, stopping midway, not following the prescribed route or sequence, exceeding the specified time limit, etc. The full score for Subject 2 is 100 points, with evaluation criteria set for failure, deduction of 20 points, 10 points, or 5 points. The exam is considered passed if the following conditions are met: ① For applicants of large buses, tractors, city buses, medium buses, or large trucks, a score of 90 or above is required; ② For other vehicle types, a score of 80 or above is required. Candidates who fail the Subject 2 exam can retake it once on the spot. If they choose not to retake or fail the retake, the exam is terminated, and the applicant must reschedule the exam after ten days. Within the validity period of the driving skill test permit, the number of exam reservations for Subject 2 and Subject 3 road driving skills cannot exceed five times. If the fifth attempt still results in failure, the scores of other previously passed subjects will be invalidated.

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What is the normal voltage for car startup?

Car startup voltage is considered normal as long as it is not lower than 11V. Under normal circumstances, the battery voltage before starting the car is between 11.8V and 12.8V, and the battery voltage after starting is between 13.2V and 14.8V. Precautions for battery usage: Keep the battery clean and dry at all times, and ensure the vent holes are unobstructed. Do not use the starter continuously; each use should not exceed 5 seconds, with a rest period of 10 to 15 seconds between two startups. A fully charged battery should not be left in a state of insufficient charge for a long time; it should be charged regularly, otherwise it may lead to scrapping. The electrolyte level should be 10 to 15mm above the plates; if the level is too low, distilled water should be added promptly, not electrolyte. Consequences of motor voltage being too high or too low: Both excessively high or low voltage in the motor will cause overheating. When the motor operates at low voltage, both the speed and the impedance of the stator winding decrease. Since the reduction in voltage is less than the reduction in impedance, the current increases. Generally, the lower the voltage, the higher the current, the higher the temperature rise, and the greater the harm to the motor. If the motor operates at low voltage for a long time, measures should be taken to reduce the degree of harm. When the voltage drops by 10%, the motor output power should be reduced by 15%. The method to reduce output power depends on the working condition of the production machinery driven by the motor.

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What Causes Car Air Conditioning to Leak Water?

Whether it is normal for a car's air conditioning to leak water depends on the situation. It is normal for water to leak from external parts of the car, such as the exhaust pipe, when the air conditioning is on. This is condensation water from the air conditioning and does not harm the car or the air conditioning system. However, if water leaks inside the car, such as under the passenger seat, it is abnormal and should be repaired at an auto repair shop. The car air conditioning system is designed to cool, heat, ventilate, and purify the air inside the vehicle. Its purpose is to provide a comfortable environment for passengers, reduce driver fatigue, and enhance driving safety. Reasons for water leakage when the car air conditioning is on: Refrigerant flows into the evaporator inside the car, where it absorbs heat from the air through contact with the evaporator. It is then compressed and expanded again in a cyclic process, gradually removing heat from the air inside the car. Since the air contains a lot of water vapor, when it encounters the very cold evaporator, it condenses into water, which then drains out from under the car's chassis. Solutions for car air conditioning water leakage: After turning off the air conditioning, open the windows for ventilation. If the leakage is abnormal, promptly visit a specialized repair shop or a 4S store for repairs to avoid affecting normal driving.

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What Are the Reasons for the Car Key Remote Not Responding?

The reasons for the car key remote not responding include: the car remote key battery is dead, which can be resolved by replacing the battery; the car's key sensor module is malfunctioning and requires inspection and repair; nearby interference sources are disrupting the key signal, which can be resolved by moving away from the interference source; the key is too far from the vehicle, making it unable to receive the remote signal—specific issues can be checked and repaired at a service center. The biggest advantage of a remote key is that, regardless of day or night, it allows for convenient long-distance locking and unlocking without needing to locate the keyhole. The remote emits a weak radio wave from the owner's vicinity, which is received by the car's antenna. The electronic control unit (ECU) identifies the signal code, and the system's actuator performs the locking or unlocking action. Modern car keys use a chip-based magnetic system. If the remote key's circuit board fails, it is similar to losing a coded key—pressing the key will not elicit any response, and a new key must be replaced. Building obstructions can also affect the car key's functionality. Radio waves have a certain penetration capability, allowing remote operation even through walls or buildings. However, as the battery power decreases, the strength of the radio waves is also affected. Thus, while normal face-to-face use is fine, radio waves may fail to penetrate when obstructed by buildings.

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What is the classification of vehicle flood levels?

Vehicle flood levels are classified from Flood Level 1 to Flood Level 6. The specific classifications are as follows: Introduction to vehicle flood level classification: Flood Level 1: Water has just reached the vehicle's chassis, and the floor may become damp, but the likelihood of significant water ingress is low, with minimal impact on the vehicle's electrical equipment. Flood Level 2: Water reaches halfway up the wheels. Due to the vehicle's incomplete sealing, water will begin to enter the interior. For lower-sedan vehicles, the water level inside may affect the seat adjustment motors and electrical components such as heating and ventilation. Flood Level 3: Water almost completely submerges the tires. At this point, the water level inside the vehicle will fully immerse the seat cushions and center console, affecting a large number of electrical components. Flood Level 4: Water reaches the engine hood. The water level inside rises to the dashboard, and the vehicle's headlights and engine intake pipes in the engine compartment begin to take in water. Flood Level 5: Water completely submerges the engine hood. Almost all electrical components inside the vehicle will be affected by the water. Flood Level 6: Water submerges the roof. The vehicle's ceiling and sunroof module will be affected, and no interior components will be spared.

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What are the main functions of an engine lubrication system?

Do I still need to display the 2021 vehicle inspection sticker?

Does touching the line with the car head in the S-curve of Subject 2 result in point deduction?

What is the normal voltage for car startup?

What Causes Car Air Conditioning to Leak Water?

What Are the Reasons for the Car Key Remote Not Responding?

What is the classification of vehicle flood levels?

Can a car without the green book be sold?

How to Replace Coolant in Lavida?

How to Remove Fog on the Outside of the Windshield?

What Are the Reasons for the Car's Electric Fan Not Spinning?