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What is the difference between the internal and external air circulation modes in a car's air conditioning system?

1 Answers

VonAlan

07/29/25 4:34pm

Introduction to the differences between internal and external air circulation modes: 1. Internal circulation mode keeps air circulating only within the vehicle, using the blower to recirculate the cabin air. 2. External circulation mode connects the cabin with the outside environment. While driving, airflow automatically enters the cabin through wind pressure, and when stationary, outside air can still enter through air ducts to the blower and then into the cabin. Below are detailed explanations of both modes: 1. External circulation: Newly purchased vehicles should use external circulation as much as possible to maintain air flow between inside and outside the car, helping to release harmful gases from the cabin. Additionally, during long highway drives, continuous use of internal circulation may lead to oxygen deficiency in the cabin, potentially causing driver fatigue and accidents. In such cases, switching to external circulation helps replenish fresh air. 2. Internal circulation: While daily driving primarily uses internal circulation, it's crucial to activate this mode during traffic jams. Congested areas have higher concentrations of exhaust fumes, and internal circulation effectively prevents external pollutants from entering the cabin. It's also essential to use internal circulation during sandstorms or dusty conditions, as it not only blocks external dust but also reduces the impact of sand on the air filter.

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What is the passenger capacity of a sedan?

A sedan typically has a passenger capacity of 5 people, while some family cars can accommodate up to 7 people. The exact number is determined by the vehicle's registration certificate. The main content on the registration certificate includes: "License Plate Number," "Vehicle Type," "Usage Nature," "Owner," "Address," "Brand Model," "Engine Number," "Vehicle Identification Number," "Registration Date," "Issuance Date," and other details. Additional information: Article 55 of the "Regulations for the Implementation of the Road Traffic Safety Law of the People's Republic of China" stipulates the following rules for passenger carrying in motor vehicles: 1. Passenger capacity: Road passenger vehicles must not exceed the approved passenger capacity, except for children who are exempt from tickets according to regulations. When the passenger capacity is full, the number of exempt children must not exceed 10% of the approved passenger capacity. 2. No passengers in cargo compartments: On urban roads, cargo motor vehicles may carry 1 to 5 temporary workers in the compartment if there is a safe space available. When the height of the cargo exceeds the compartment's sideboards, no one is allowed on the cargo. 3. Motorcycle passenger requirements: Children under 12 years old are not allowed to ride on the back seat of a motorcycle, and light motorcycles are not allowed to carry passengers.

Why Has smart Been Completely Discontinued?

Due to the tightening emission standards and the gradual advancement of new energy vehicles, the traditional fuel-powered smart models can no longer meet the market demands in China. The details are as follows: 1. Reason: According to foreign media reports, Mercedes-Benz will discontinue the sales of its pure electric vehicle brand Smart in the United States and Canada, attributing this decision to the 'decline in the microcar market' and high certification costs. In China, the fuel-powered smart models may also be discontinued. 2. New Generation: Mercedes-Benz has partnered with Zhejiang Geely Holding Group to establish a joint venture in China, aiming to produce the next generation of Smart cars, with global sales expected to begin in 2022. During this period, many models can perfectly replace the urban commuting attributes of the Mercedes-Benz smart.

Which way to turn the steering wheel when the left side is wide in Subject 2 reverse parking?

Turn the steering wheel to the left when the left side is wide. Here is the information introduction: 1. Reverse parking skills: If the speed is not well controlled during reverse parking, it is basically half a failure. Students must learn the correct posture for pressing the clutch during practice. The ball of the foot should press on the clutch pedal, with the heel touching the ground as a support point. When the clutch is pressed to the lowest point, the knee should remain slightly bent to maintain an appropriate speed. 2. Reverse parking: Reverse parking is a mandatory item for obtaining a small car driving license after 2013. It tests the driver's ability to operate the car in a confined space. Reverse parking is an assessment point in the driver's test, which involves correctly maneuvering the vehicle into the garage from both sides while in motion.

Will the automatic return of turn signals result in point deduction?

No points will be deducted if the turn signals automatically return and are turned on in a timely manner. Below is an introduction to the relevant content of the Subject 3 driving test: 1. Test regulations: The specific subjects of the Subject 3 test are road driving skills and safety and civilized driving knowledge tests, with full scores of 100 points each. A score of 90 points or above is required to pass. 2. Study hour regulations: Subject 3 consists of a total of 40 study hours, including 16 hours of theory, 4 hours of simulated driving, and 20 hours of practical driving. According to the teaching syllabus, driving practice is recorded with time cards, and study hours are cumulative. Each student can sign in for a maximum of 4 study hours per day.

How Many Wheels Does a Sedan Have?

A sedan has four wheels plus one spare tire. Extended information about tires is as follows: 1. Introduction: Tires are circular elastic rubber products mounted on various vehicles or machinery for ground rolling. They are usually installed on metal rims to support the vehicle body, cushion external impacts, achieve contact with the road surface, and ensure the vehicle's driving performance. Tires are often used under complex and demanding conditions, enduring various deformations, loads, forces, and high and low temperatures during operation. Therefore, they must possess high load-bearing performance, traction performance, and cushioning performance. Additionally, they are required to have high wear resistance and flex resistance, as well as low rolling resistance and heat generation. 2. Performance: As the only component of a car that contacts the ground, the performance of tires directly affects the safety of the driver and passengers. For this reason, various countries have established clear requirements for tire safety performance. With the rapid advancement of the automotive industry, consumers have begun to pay attention not only to the safety performance of tires but also to the overall comfort, handling stability, NVH, and other performance aspects of the vehicle.

Who uses the Cyclone Magnum?

Shouma Gou's car. Below is the relevant introduction of Cyclone Magnum: 1. Introduction of Cyclone Magnum: Cyclone Magnum is the racing car used by Gou in the Japanese anime "Bakusou Kyoudai Let's & Go!!", which is the third-generation Magnum racing car designed by Shouma Gou himself. The first generation is Magnum Saber, the second generation is Victory Magnum, and this is the third-generation Cyclone Magnum. 2. The strength of Cyclone Magnum: In WGP, Cyclone Magnum was modified into a super racing car with a GP chip, competing with top racers from around the world and pushing the limits of speed. During the race against the Italian team at the Tower Circuit, all the Japanese team's cars were completely destroyed by the Death Dance performed by Carlo and others. However, the TRF team did not give up the race; instead, they assembled all the parts onto Gou's Cyclone Magnum. Surprisingly, the makeshift car turned out to be incredibly fast!

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