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What Are the Symptoms of a Bad CV Joint in a Car?

If the CV joint in a car is damaged, regular "clicking" noises will occur during normal steering or when driving over bumps. In severe cases, it may even lead to a loss of power. A "clicking" sound during steering is usually caused by damage to the outer CV joint, although the inner CV joint could also be the culprit, but the outer CV joint is more likely to be at fault. A "clicking" sound when driving over bumps is typically due to damage to the inner CV joint. In fact, if the inner CV joint is damaged, the noise will also occur when driving straight. Below are some relevant explanations: 1. Definition of a CV joint: A CV joint, also known as a constant velocity joint, connects the drive shaft to the wheel. It is a crucial component in the car's drivetrain, ensuring that power is continuously transmitted to the wheels in any direction, especially when the wheels are bouncing. 2. Classification of CV joints: There are two common types of CV joints used in passenger cars. One is the fixed-type CV joint, which allows only relative rotation between the driving and driven shafts during torque transmission without axial displacement. This type is usually located near the wheel and is commonly referred to as the outer CV joint. The other is the plunging-type CV joint, which not only allows relative rotation between the driving and driven shafts during torque transmission but also permits axial displacement. This type is typically found near the drive axle and is commonly referred to as the inner CV joint.

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What does an auto-dimming rearview mirror mean?

An auto-dimming rearview mirror is a feature of the vehicle's interior rearview mirror. When the headlights of a following vehicle shine onto the interior rearview mirror, it can cause glare. If the mirror is equipped with an auto-dimming function, this feature will activate, ensuring optimal visibility for the driver without causing glare. Below are related details: 1. Explanation of auto-dimming rearview mirror: The auto-dimming rearview mirror has two photodiodes—one installed on the front of the mirror and one on the back—to detect light from the front and rear of the vehicle. 2. Function of auto-dimming rearview mirror: When the headlights of a following vehicle reflect onto the mirror, the signals from the two photodiodes compare the light intensity. The electronic controller then applies voltage to darken the mirror's color.

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What Causes the Ticking Sound in the Engine?

Reasons for the ticking sound in the engine: 1. Aging or loosening of engine mounts: Engine mounts are rubber blocks placed between the engine and the frame. Their purpose is to reduce vibration and absorb shocks during engine operation, as well as to secure the engine. Once these mounts age or become loose, the engine may shake, and in severe cases, produce a "ticking" noise. This can usually be resolved by replacing the engine mounts. 2. Overly rich air-fuel mixture: When the engine's air-fuel mixture is too rich, symptoms include difficulty accelerating after starting, uneven engine operation, black smoke from the exhaust pipe, a ticking noise from the engine, reduced engine power, and increased fuel consumption. This is often related to carbon buildup or clogged filters and generally does not require major repairs. 3. "Piston slap" noise: Due to poor lubrication or excessive wear of the piston and cylinder walls, the clearance between the piston and cylinder exceeds normal tolerances. During operation, the piston skirt strikes the cylinder wall, producing a clear "ticking" sound, which is usually more noticeable at idle or low speeds.

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What Causes White Smoke from a Car?

White smoke from a car fault phenomenon: 1. The exhaust pipe emits a milky white oil mist: The main reason is poor oil vaporization, which causes unburned oil to be discharged from the exhaust manifold, forming a milky white smoke. This is more common when starting the engine in winter due to low temperatures leading to poor fuel atomization. It usually disappears as the engine temperature rises after starting. 2. The exhaust manifold emits a large amount of water vapor white smoke, with water droplets at the exhaust pipe outlet: The main reason is water vapor formed due to moisture in the cylinder or gasoline. Diagnosis and elimination of white smoke faults in cars: 1. White smoke disappears as temperature rises: When a car parked in winter or during the rainy season is started for the first time, white smoke is often visible. Once the engine temperature rises, the white smoke will disappear, and this condition does not require repair. If the exhaust manifold emits black smoke after the engine temperature rises, it indicates that the cylinder pressure is too low or individual cylinders are not working, and inspection and elimination are required. 2. When the engine is running, the exhaust manifold emits a large amount of water vapor white smoke: Check whether there is water in the fuel tank, whether the cylinder gasket is damaged, whether the cylinder block has cracks, and whether the cylinder sleeve sealing ring is in good condition, etc.

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What are the reasons for the sudden disappearance of the reversing camera?

The reasons for the sudden disappearance of the car's reversing camera are as follows: 1. Camera failure: You can purchase and install a new one. It's best to buy a camera with an illumination power supply so it can be seen at night. 2. Loose power cord: This causes a power supply failure for the camera. Simply plug the power cord back in firmly. Also, check the plug for any water marks, as power supply issues are often caused by short circuits due to water marks. 3. The line is pinched off: You can use sealant to glue and secure it firmly to avoid being pinched off during driving. 4. Display screen damage: If the display screen has problems, the reversing camera will definitely not display. So carefully observe whether the display screen is broken or if the surrounding wires are loose. If all else fails, you can only buy a new one and install it.

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What is the Difference Between a Reversing Radar and a Reversing Camera?

The differences between a reversing radar and a reversing camera: 1. Different viewing angles: The reversing radar cannot directly see objects behind the car, especially blind spots or objects that are too thin or too low; whereas the reversing camera features digital display + audio alerts + real-time image display + night vision + car multimedia functions. Through the rear camera, all obstacles within the visible range can be seen on the central control screen, allowing the driver to better understand the situation behind. 2. Different distance measurement: The reversing camera cannot measure the distance between obstacles and the rear of the car, while the reversing radar can continuously remind the driver of the distance to objects behind the car through the rear radar module when reversing. When reaching a dangerous distance, the buzzer starts beeping, with the intermittent/continuous urgency of the beeps reminding the driver of the approaching obstacle and prompting timely stopping. 3. Different installation difficulties: Installing a reversing camera is relatively simpler compared to a reversing radar, but the reversing radar is more proactive than the reversing camera. For example, when reversing, the driver needs to first observe the dynamics on the display screen with the reversing camera, which requires looking to understand the situation. However, the reversing radar can provide audio alerts if there is an obstacle on the right side that is too close to the car while the driver is observing the left side.

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Which subject needs to be retaken if all points are deducted?

What Are the Symptoms of a Bad CV Joint in a Car?

What does an auto-dimming rearview mirror mean?

What Causes the Ticking Sound in the Engine?

What Causes White Smoke from a Car?

What are the reasons for the sudden disappearance of the reversing camera?

What is the Difference Between a Reversing Radar and a Reversing Camera?

Why is the reverse gear marked as R?

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