Where to Take the Subject 4 Exam?

What to Do When the Car Air Conditioner Won't Turn Off?

Reasons why the car air conditioner won't turn off are as follows: 1. The air conditioner button is damaged. Solution: Replace the air conditioner button. 2. The car air conditioner control circuit is faulty. Solution: It is necessary to go to a professional repair shop as soon as possible for repairs. Information about car air conditioners is as follows: 1. The car air conditioning device (air-conditioning-device), referred to as car air conditioner, is used to adjust and control the temperature, humidity, air cleanliness, and air flow inside the car compartment to the optimal state, providing a comfortable riding environment for passengers and reducing travel fatigue. 2. The car air conditioner generally includes a refrigeration device, heating device, and ventilation device. This combined device makes full use of the limited space inside the car, with a simple structure and easy operation.

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What is the working principle of a manual transmission?

Manual transmission works by having multiple different gears inside the gearbox. By combining gears of different sizes, it can adjust the engine's torque and speed. Low torque can be exchanged for high speed, while low speed can be exchanged for high torque. Information about manual transmissions is as follows: 1. Manual Transmission, also known as manual gearbox, is a type of transmission device and the most basic type of automotive transmission. 2. The function of a manual transmission is to change the gear ratio, also known as the gear ratio. Based on the principle of lever torque, it uses the largest diameter gear of the low-speed gear with the longest radius to amplify the engine torque, assisting the vehicle in starting to move forward.

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What does it mean when the engine power is reduced?

The reasons for displaying reduced engine power include: 1. Excessive carbon buildup in components such as cylinders, throttle valves, and spark plugs: When there is too much carbon buildup inside the engine, the vehicle's ignition energy decreases, intake efficiency drops, ultimately leading to reduced engine power and symptoms like weak idling. 2. Malfunction in the fuel system: Using an incompatible fuel grade can cause a decrease in the vehicle's output power, resulting in reduced power. Alternatively, if the fuel tank vent is blocked or components like the fuel tank switch, fuel filter, or fuel lines between the tank and carburetor are partially clogged, the required fuel supply cannot be met, leading to overly lean air-fuel mixture and weak engine acceleration. 3. Severe wear of pistons, piston rings, or cylinders: This increases the clearance between pistons, piston rings, and cylinders, reducing sealing effectiveness and causing cylinder head leakage, which lowers cylinder compression pressure. 4. Engine overheating: This leads to poor lubrication, increased mechanical wear, reduced engine power, and higher fuel consumption.

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Can Non-Independent Suspension Be Replaced with Independent Suspension?

Non-independent suspension cannot be replaced with independent suspension. If a car uses non-independent suspension, it is generally not possible to modify it into independent suspension. Most cars use independent suspension for the front suspension and non-independent suspension for the rear suspension. Information about non-independent suspension and independent suspension is as follows: 1. The structural feature of non-independent suspension is that the wheels on both sides are connected by an integrated frame. The wheels, together with the axle, are suspended under the frame or body through an elastic suspension system. It has the advantages of simple structure, low cost, high strength, easy maintenance, and minimal changes in front-wheel alignment during driving. 2. Independent suspension mostly uses coil springs, so for lateral forces, vertical forces, and longitudinal forces, guide devices (i.e., rods) are required to bear and transmit these forces. Therefore, some cars use multi-link suspension to reduce weight and simplify the structure.

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Do Vehicle Fuel Injectors Need Cleaning?

Vehicle fuel injectors do require cleaning. The recommended cleaning interval for fuel injectors is every 2 years or 50,000 kilometers. Additionally, if the vehicle frequently operates on poor road conditions, the fuel injectors should be cleaned earlier. Clogged fuel injectors can significantly impact the vehicle's power output, and in severe cases, may even prevent the engine from starting. Below is relevant information about fuel injectors: 1. The fuel injector (fuel-spray-nozzle) is essentially a normally closed valve. When the electromagnetic coil is energized, it creates a magnetic force that lifts the needle valve, opening the injection port. Fuel is then sprayed at high speed through the annular gap between the needle valve head and the injection port, forming a fine mist that facilitates complete combustion. 2. The primary function of automotive fuel injectors is to coordinate with the valve timing mechanism and ignition timing, injecting gasoline into the cylinder in precise quantities and at the right moment. This allows the spark plugs to ignite the fuel mixture, generating power for the vehicle.

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What is the passing score for Subject 2 driving test?

Subject 2 has a full score of 100 points, with evaluation criteria set for failing, deducting 20 points, deducting 10 points, and deducting 5 points. The test is considered passed under the following conditions: ① For applicants applying for 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. The test items for small vehicles C1 and C2 include reversing into a garage, parallel parking, stopping and starting on a slope (canceled for C2), turning at a right angle, and driving on an S-curve (commonly known as S-turn) as five mandatory items (some regions have a sixth item, high-speed card collection). The test items for large vehicles A1, A2, A3, B1, and B2 include stake test, stopping and starting on a slope, parallel parking, passing a single-plank bridge, driving on an S-curve, turning at a right angle, passing a width-limited gate, passing continuous obstacles, driving on bumpy roads, making a U-turn on a narrow road, as well as simulated highway driving, continuous sharp turns on mountain roads, tunnels, rainy (foggy) conditions, slippery roads, and emergency handling. If a candidate fails the Subject 2 test on the first attempt, they are allowed one retake. If the candidate does not take the retake or fails the retake, the test is terminated, and the applicant must reschedule the test after ten days. Within the validity period of the driving test permit, the number of rescheduling for Subject 2 and Subject 3 road driving skill tests must not exceed five times. If the candidate fails the fifth rescheduled test, the results of other passed subjects will be invalidated.

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Where to Take the Subject 4 Exam?

What to Do When the Car Air Conditioner Won't Turn Off?

What is the working principle of a manual transmission?

What does it mean when the engine power is reduced?

Can Non-Independent Suspension Be Replaced with Independent Suspension?

Do Vehicle Fuel Injectors Need Cleaning?

What is the passing score for Subject 2 driving test?

Do I need a wheel alignment after getting a tire balance?

How to Start a Ford Focus?

What are the operating steps for an automatic transmission?

Is the coolant for the BMW 5 Series exclusive?