How many chances are there in one driving test for Subject 2?

Is it better to use 5W30 or 5W40 engine oil for Focus?

It is better to use 5W30 engine oil for Focus. It is essential to use engine oil with the appropriate quality grade, which is the key to ensuring the normal operation of the engine. The following are the relevant introductions: 1. Engine oil grade: The engine oil grade usually indicates viscosity and quality. The viscosity of lubricating oil is mostly marked with SAE grade, and SAE is the abbreviation of "Society of Automotive Engineers" in English. 2. Meaning of 5W30: In the engine oil 5W30, "5" indicates the low-temperature fluidity of the engine oil. The smaller the number, the lower the ambient temperature that can be used; the better the protection ability for the engine during cold starts. 5 represents resistance to external low temperatures of -30°C; 30 represents the standard kinematic viscosity at 100 degrees Celsius is 30. This number indicates the high-temperature resistance index of the engine oil. The larger the number, the better the protection performance of the engine oil at high temperatures.

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Is Engine Compartment Wiring Harness Maintenance Necessary?

Automobile engine wiring maintenance is necessary. Here are the relevant explanations: 1. Wiring harness aging: The engine wiring harness inside a car is generally composed of multiple strands of copper wires wrapped in plastic. During daily driving, the engine compartment temperature is very high. When heated, the plastic covering will release plasticizers and other chemicals, which react with the internal copper wires, leading to reduced plastic strength and increased copper wire resistance. This ultimately causes the wiring harness to age and poses a risk of short circuits. Rubber hoses in the engine compartment are unsaturated polymer hydrocarbons, and aged rubber is also prone to oxidation, which can cause vehicle self-ignition. 2. Engine wiring oil contamination: Oil contamination on engine wiring significantly affects the engine's working quality and efficiency. This can result in abnormal vibrations, increased noise, insufficient power, decreased fuel economy, and greatly shortened vehicle lifespan. Therefore, for older vehicles' engines and wiring, regular maintenance is even more essential to extend their service life as much as possible.

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What does the A symbol on the car dashboard mean?

The A symbol illuminated on the dashboard can indicate two scenarios: 1. It represents mileage counting. The car's odometer can display two separate mileage counts: (1) Indicates the total mileage driven by the vehicle. (2) Used for individual trip counting. You can toggle between these displays using the black button on the dashboard. When switched to A, it can be used to calculate the distance traveled on a full tank of fuel - reset it after refueling, then reset again after the next refuel. It can also track maintenance intervals or display the distance between two locations (reset at departure). Resetting is simple - just long-press the black button. 2. It indicates the auto start-stop system is deactivated. When the auto start-stop is turned off, the dashboard typically displays a circled A with "OFF" below it. Some models may show a circled A with a slash through it. The exact display varies depending on the vehicle model.

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What to Do When the Brake Pedal Won't Depress and the Car Won't Start?

The solutions for when the brake pedal won't depress and the car won't start are: 1. Try restarting the ignition and firmly press the brake pedal; it should return to normal once the car starts. 2. If the issue persists after multiple attempts, seek a nearby repair shop to resolve the fault before continuing to drive. Additional tips for regular braking: 1. At low speeds, you can perform emergency braking by fully depressing the brake pedal in case of sudden events ahead, but avoid doing so at high speeds to prevent skidding or rollover. 2. Under normal road conditions, apply gradual braking by pressing the clutch pedal while releasing the accelerator, downshifting to a lower gear, and then lifting the clutch pedal once the speed reduces before pressing the brake pedal to a complete stop. 3. On long downhill slopes in mountainous areas or during continuous braking that may cause overheating, use intermittent braking by alternately pressing and releasing the brake pedal to effectively prevent excessive brake system temperatures.

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Which is better, 3M car film or LLumar?

LLumar and 3M are both veteran brands in the automotive film industry, ranking first and second in popularity in China. Their product quality is unquestionable—LLumar has a 60-year development history and strong manufacturer capabilities, while 3M holds the first patent for heat-insulating film and excels in innovation. The differences between the two are: 1. LLumar is slightly more expensive than 3M film; 2. LLumar's top-tier films are superior; 3. LLumar has more authorized stores than 3M. 4. Although both have a long history and technical support, with products being economical and durable, I personally prefer LLumar. LLumar primarily focuses on window films, whereas 3M offers a wider variety of products. 1. While this doesn’t directly relate to product quality, if cars stopped using films, the LLumar brand would cease to exist, whereas 3M would remain largely unaffected. Thus, automotive film is the lifeline of LLumar—its specialization makes it professional. 2. LLumar is Eastman's flagship brand, treated like a favored child. Its products are renowned for safety and durability. Truly good products aren’t just about excelling in one performance aspect but about how practical and effective they are in real-world use.

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Should the Car Battery Be Replaced If It Runs Out of Power?

If the car battery runs out of power, it does not need to be replaced; simply recharge it in time. Below are the specific classifications of car batteries (also known as storage batteries): 1. Conventional Battery: The plates of a conventional battery are made of lead and lead oxide, with the electrolyte being an aqueous solution of sulfuric acid. Its main advantages are stable voltage and low cost; the disadvantages are low specific energy (i.e., the amount of electrical energy stored per kilogram of the battery), short service life, and frequent daily maintenance. 2. Dry-Charged Battery: Its full name is dry-charged lead-acid battery. Its main feature is that the negative plate has a high capacity for storing electricity. In a completely dry state, it can retain the stored charge for up to two years. When in use, you only need to add the electrolyte and wait for 20-30 minutes before it can be used. 3. Maintenance-Free Battery: Due to its structural advantages, the maintenance-free battery consumes very little electrolyte and basically does not require the addition of distilled water during its service life. It also features resistance to vibration, high temperature, small size, and low self-discharge. Its service life is generally twice that of a conventional battery.

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How many chances are there in one driving test for Subject 2?

Is it better to use 5W30 or 5W40 engine oil for Focus?

Is Engine Compartment Wiring Harness Maintenance Necessary?

What does the A symbol on the car dashboard mean?

What to Do When the Brake Pedal Won't Depress and the Car Won't Start?

Which is better, 3M car film or LLumar?

Should the Car Battery Be Replaced If It Runs Out of Power?

What procedures are required for towing an RV?

What Causes Abnormal Noise in the Air Conditioning System?

Where is the computer plug of Renault located?

Internal Structure of Automotive Mufflers?