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What is the difference between internal circulation and external circulation in a car?

1 Answers
LaAlice
07/29/25 9:47pm
The difference between internal circulation and external circulation in a car is: 1. The indicator for internal circulation is an arrow pointing inward; the symbol for external circulation is from outside to inside. 2. Different functions: Internal circulation effectively prevents external dust and harmful gases from entering the car, improving the cooling and heating efficiency of the air conditioning; external circulation draws fresh air from outside into the car, maintaining air quality inside the vehicle. The methods for using car air circulation are: 1. Use internal circulation during traffic jams and external circulation during high-speed driving; 2. The use of internal and external circulation should be combined with air conditioning and heating; 3. Use external circulation during long-distance driving to allow fresh air from outside to enter the car, avoiding excessively low oxygen levels inside the vehicle.
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What is the fuel tank capacity of the Corolla?

The fuel tank capacity of the Corolla is 55L, and the recommended gasoline specification is 92 octane or higher unleaded gasoline. The size of the fuel tank is directly related to the vehicle's fuel consumption, and generally, a full tank can support a driving range of over 500 kilometers. Most car manufacturers follow a general rule that a full tank of fuel should support a driving range of around 600 kilometers, and not less than 500 kilometers. Method to check the fuel tank capacity of the Corolla: Observe the reading on the fuel gauge inside the vehicle. If there are no other issues, the fuel level will be accurately reflected on the gauge. The fuel gauge typically has 5 to 6 segments, with each segment representing the remaining fuel capacity in the tank. It is generally recommended to refuel when the fuel gauge shows only two segments remaining to avoid running out of fuel while driving.
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What does shiftlock mean in a car?

The shiftlock button refers to the gear shift lock device. 'Shift' means changing gears, and 'lock' means to secure. The primary function of this device is to lock the gear in place, preventing it from moving to another gear, thus ensuring driving safety. It is a specialized device for unlocking under specific circumstances. For example, when the vehicle cannot start due to a dead battery or malfunction and is stuck in P (Park) gear, the vehicle cannot be towed. In this case, pressing the shiftlock button allows the gear lever to move to N (Neutral) gear, enabling the vehicle to be towed. P gear: 'Parking' means 'to park.' It is the parking gear used when the vehicle is parked. Upon reaching the destination or when needing to park for an extended period, shift the gear lever into this position. Note: The vehicle must be completely stopped before shifting into P gear; shifting into P gear before the vehicle has fully stopped can damage parts of the automatic transmission. When in P gear, the wheels are mechanically locked, preventing the vehicle from moving forward or backward, which is essential when parking on a slope. Additionally, during brief stops (like at traffic lights), it is best not to shift into P gear to avoid severe damage to the entire transmission in case of a rear-end collision. R gear: 'Reverse' means 'to go backward.' Whether manual or automatic, R is the reverse gear. Shifting into R gear makes the vehicle move backward. This gear should only be engaged when the vehicle is stationary and the engine is idling. Never use R gear while the vehicle is moving forward, and be particularly cautious with accelerator control when reversing. N gear: 'Neutral' means 'neutral,' also known as the neutral gear. At traffic lights, you can shift into this gear and press the brake pedal. If the wait is longer, it is advisable to engage the handbrake, allowing your foot to rest off the brake pedal. A common misconception is that shifting into N gear while coasting downhill or at high speeds saves fuel. This is a serious mistake; not only does it not save fuel, but it can also damage the transmission. S gear: 'Sport' means 'sport' and indicates the sport mode in a car. When this gear is engaged, the transmission delays shifting to provide more power, typically used when overtaking. M gear: 'Manual' means 'hand control,' indicating the manual mode in a car. Similar to manual transmission vehicles, it requires manual gear shifting. L gear: 'Low' means 'low speed,' indicating the low-speed forward gear in a car. When this gear is engaged, the transmission operates only in low gear (equivalent to first gear in a manual transmission) and does not automatically shift to other gears based on speed changes. This gear is generally used when climbing or descending steep slopes. In low gear, the drive wheels output more torque, providing sufficient power to climb steep slopes. Prolonged braking can overheat the brake pads, reducing braking efficiency, which is dangerous on long descents or steep slopes. Engaging L gear uses the engine's low RPM to control the vehicle's movement, eliminating the need for constant braking. D gear: 'Drive' means 'to drive.' Shifting into this gear and pressing the accelerator allows the vehicle to move. In this gear, the transmission automatically shifts based on speed and throttle conditions. At traffic lights, you can stay in D gear while pressing the brake pedal.
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How to Connect Bluetooth in Mercedes-Benz?

To connect Bluetooth in a Mercedes-Benz, follow these steps: 1. Turn on your phone's Bluetooth and set it to be discoverable; 2. Locate and enable the Bluetooth option from the car's central control screen; 3. Search for Bluetooth devices on your phone and pair with the car's Bluetooth. The initial pairing password is usually 0000 or 1234; 4. Once successfully paired, you can play songs from your phone through the car's multimedia system. Taking the 2021 Mercedes-Benz E-Class 260L as an example: its dimensions are 5078mm in length, 1860mm in width, and 1484mm in height, with a wheelbase of 3079mm. It has a top speed of 230 km/h, a fuel tank capacity of 66 liters, a maximum horsepower of 184, and a maximum power of 135 kW. The 2021 Mercedes-Benz E-Class 260L is equipped with a 9-speed automatic transmission, multi-link independent suspension on both front and rear, and features such as front and rear parking radar, auxiliary camera, cruise control, and driving mode switching.
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What is the difference between C1 and C2 driver's licenses?

The differences between C1 and C2 driver's licenses are: 1. Different types of vehicles allowed: C1 is for manual transmission small vehicles; C2 is for automatic transmission small vehicles. 2. Different ranges of vehicles allowed: C1 permits driving all vehicle types under C1, C2, C3, and C4; C2 permits driving vehicle types under C2, C3, and C4. The full name of a driver's license is a motor vehicle driving license, also known as a driver's license, which is a certificate required by law for motor vehicle drivers. Driving a motor vehicle requires certain driving skills. Without these skills, driving a motor vehicle recklessly could lead to traffic accidents. Generally, people without a license cannot drive on the road. For those who have mastered safe driving techniques, the document that allows them to drive vehicles on the road is the driver's license.
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What is the purpose of a clutch?

Clutch is a component that ensures smooth vehicle starting and seamless gear shifting. It is located inside the flywheel housing between the engine and transmission, with the clutch assembly secured by screws to the rear plane of the flywheel. The output shaft of the clutch serves as the input shaft of the transmission. During driving, the driver depresses or releases the clutch pedal as needed to temporarily disconnect or gradually engage the engine with the transmission, thereby cutting off or transmitting the engine's power to the transmission. The clutch functions during vehicle starting and gear shifting when there is a speed difference between the primary and secondary shafts of the transmission. The engine's power must be disconnected from the primary shaft first, allowing the synchronizer to effectively match the speed of the primary shaft with that of the secondary shaft. After engaging the gear, the clutch then reconnects the primary shaft with the engine's power to continue power transmission.
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Where is the tire pressure monitoring sensor located?

Tire pressure sensors are generally installed on the tires, usually at the valve stem position. Below is an introduction to tire pressure sensors: 1. Installation location: Tire pressure sensors can be divided into internal and external types. Internal sensors are installed inside the tire, which is relatively more stable and provides more accurate temperature monitoring data. External sensors are attached outside the valve stem, which are relatively cheaper and easier to install, but the temperature monitoring may have a difference of 2-3 degrees compared to internal sensors. 2. Display screen: The tire pressure monitoring display is usually placed on the dashboard. The middle position of the dashboard contains many electronic devices, which can cause some interference with wireless radio frequency, especially devices like electronic eyes.
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