How Many Attempts Are Allowed for the Subject 3 Theory Test?

What does 100V on tires mean?

The marking 100V on tires refers to two parameters of the tire: load capacity and speed. 100 is the load index of the tire, meaning the maximum load capacity at the rated speed is 800KG. V represents the speed rating, indicating the maximum speed the tire can support, with V corresponding to a speed of 240KM/H. Here are some related explanations: 1. The meaning of 100V: The 100 on car tires refers to the maximum load capacity of the tire, while V stands for 240 kilometers per hour. 2. The dangers of exceeding 100: If the load on the car tire exceeds 100, it means the service life of the tire will be greatly shortened. In severe cases, it can pose significant safety hazards to the owner and may cause unavoidable harm to both the owner and pedestrians on the road.

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What Do Maximum Power and Maximum Torque Mean?

Maximum power refers to the maximum power output that an engine can achieve, measured in kilowatts (kW) or horsepower (Ps). Maximum torque is also an important parameter of engine performance, representing the average moment of force output from the crankshaft during engine operation, measured in Newton-meters (N·m). Below are the relevant details: 1. Power and torque are indicators of a car's performance: Power and torque are crucial data for a car's engine and serve as the primary basis for evaluating a vehicle's performance. Among them, maximum power determines the car's top speed and mid-to-late-stage acceleration capability, while maximum torque determines the car's initial acceleration time and burst power. 2. Maximum power: Maximum power refers to the maximum power output that an engine can achieve, measured in kilowatts (kW) or horsepower (Ps). As the engine speed increases, the engine's power also increases accordingly. When a certain speed is reached, the power will no longer increase, so the corresponding engine speed (rpm) is also noted when specifying the maximum power. 3. Engine maximum power is directly related to speed: Initially, the power increases with the rise in speed. However, once the output reaches its maximum, the power will decrease as the speed continues to increase. Different engines have different maximum power speeds, with typical gasoline engines reaching maximum power at 5000-8000 rpm, while diesel engines achieve it at 3000-5000 rpm. 4. Maximum torque: Maximum torque is also an important parameter of engine performance, representing the average moment of force output from the crankshaft during engine operation, measured in Newton-meters (N·m). The magnitude of torque is directly related to engine speed. The greater the torque, the more power the engine outputs, and the faster the crankshaft speed changes, resulting in better climbing ability, initial acceleration, and overall acceleration performance of the car. 5. Maximum torque is related to the intake system: The maximum torque of an engine is influenced by the design of the intake system, fuel supply system, and ignition system. At a certain speed, when these systems achieve optimal performance matching, the maximum torque is reached. Additionally, the speed at which maximum torque occurs depends on the design of the engine's valve timing and bore-to-stroke ratio. Generally, turbocharged engines use a DOHC (Double Overhead Camshaft) design to compensate for low-speed torque issues, balancing high-speed performance with low-speed, high-torque characteristics.

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What does autonomous driving L2 level mean?

Autonomous driving L2 level is classified as semi-autonomous driving, which enables the vehicle to operate multiple functions while requiring the driver to control a few functions. Below are two essential systems that autonomous driving L2 level must have: 1. Adaptive Cruise Control System: Also known as ACC adaptive cruise control system, the latest commercial version is the third-generation ACC adaptive cruise control system. It uses front radar sensors to collect signals and automatically follows the preceding vehicle for acceleration and deceleration. It also features the Stop-Go function, making it not only suitable for highway conditions but also ideal for urban driving. The AEB (Automatic Emergency Braking) system assists in braking when the distance to the preceding vehicle or pedestrian is less than the safe distance, helping to prevent collisions. 2. Lane Keeping System: During turns, the vehicle can easily deviate from its lane due to inaccurate steering by the driver, especially for novice drivers who have just obtained their licenses. Once the vehicle enters the opposite lane during a turn, it can be very dangerous.

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What are the effects of shock absorber oil leakage?

Shock absorber oil leakage at the initial stage will not cause significant impact, as the leakage rate is relatively slow. However, over time, the lack of oil will result in the shock absorber losing its damping function. When driving, the vehicle will experience noticeable shaking and bumping (body roll), and when encountering potholes, the wheels may produce a "bang" collision sound, causing considerable damage to the vehicle's suspension. When shock absorber oil leakage occurs, it should be addressed as soon as possible. Below is relevant information: 1. The role of shock absorbers: As the most critical component in a vehicle's vibration filtering system, shock absorbers primarily absorb vibrations and impacts caused by uneven road surfaces during driving, thereby providing a comfortable driving and riding environment for vehicle occupants. 2. The hazards of damaged shock absorbers: Once a shock absorber is damaged, it will greatly affect the driving comfort of the vehicle, and in severe cases, it may even pose a safety hazard. 3. Whether to replace a leaking shock absorber: Regarding whether a leaking car shock absorber can be left unreplaced, the key factor is the severity of the leakage. If it's only a minor seepage, replacement may not be necessary; however, if the shock absorber is leaking severely, it should be replaced promptly.

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What are the differences between two-wheel drive and four-wheel drive vehicles?

The differences between two-wheel drive and four-wheel drive vehicles are as follows: 1. Performance differences: Four-wheel drive vehicles have outstanding power and strong off-road capability, making them suitable for off-road driving. Four-wheel drive vehicles can distribute the engine's power to all four wheels, significantly improving the vehicle's handling and passage ability. Four-wheel drive systems are mostly found in SUV models. Two-wheel drive vehicles balance urban commuting and off-road driving, with two wheels driving the vehicle. Two-wheel drive vehicles are further divided into front-wheel drive and rear-wheel drive. Rear-wheel drive is more common in performance cars, while front-wheel drive is more common in family cars. 2. Structural principle differences: As the name suggests, two-wheel drive vehicles have only two wheels responsible for driving the vehicle. Front-wheel drive means the two front wheels are responsible for driving, while rear-wheel drive means the two rear wheels are responsible for driving. Four-wheel drive vehicles are further divided into natural four-wheel drive, full-time four-wheel drive, and part-time four-wheel drive. Natural four-wheel drive means all four wheels have driving functions, full-time four-wheel drive means all four wheels are always in driving state, and part-time four-wheel drive means the driver can manually switch between four-wheel drive and two-wheel drive.

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Which oxygen sensor is faulty when P0420 code appears?

P0420 refers to the failure or low efficiency of the three-way catalytic converter, indicating potential issues with either the catalytic converter or the oxygen sensor. Here are the details: 1. Troubleshooting P0420: When this occurs, check for signs of aging in the three-way catalytic converter. If the converter shows no aging, the issue likely lies with the oxygen sensor. If the oxygen sensor is faulty, try soaking it in toilet cleaner to remove carbon deposits. If the sensor still doesn't function properly after this, replacement is necessary. 2. Solutions for P0420 code: This code may indicate two possibilities - aging/blockage of the three-way catalytic converter or oxygen sensor failure. Inspect the catalytic converter's condition; if blocked, clean it, or replace if severely aged. For oxygen sensor issues, either clean or replace it. 3. Importance of oxygen sensors: These sensors are crucial for vehicles. By analyzing exhaust oxygen concentration, they monitor engine performance. A faulty sensor leads to increased fuel consumption, reduced power, and excessive emissions. All modern vehicles have oxygen sensors, which are consumable parts requiring periodic cleaning or maintenance.

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How Many Attempts Are Allowed for the Subject 3 Theory Test?

What does 100V on tires mean?

What Do Maximum Power and Maximum Torque Mean?

What does autonomous driving L2 level mean?

What are the effects of shock absorber oil leakage?

What are the differences between two-wheel drive and four-wheel drive vehicles?

Which oxygen sensor is faulty when P0420 code appears?

What does the yellow light 'off' on the car dashboard mean?

Can 95 and 98 Octane Gasoline Be Mixed?

What does a 3-lock off-road vehicle mean?

Do I Need to Change Back If the Tire Is Mounted Backwards?