How to Identify Battery Model Numbers?

Are all questions in Subject 4 multiple-choice?

Exam questions include image-based questions, scenario identification questions, and text-based questions. Below is an introduction to the Subject 4 exam: 1. Scope: Depending on the type of driver's license being tested, 50 questions are randomly selected from the corresponding Subject 4 question bank in proportion. For small vehicle licenses, questions are selected from a pool of 1235 questions, while for large vehicle licenses, questions are also selected from a pool of 1235 questions, with each question worth 2 points. 2. Time: The exam duration is 45 minutes. If 12 points (6 questions) are answered incorrectly during the exam, the session will be terminated. 3. Question types: The exam includes true/false questions (questions 1--22), single-choice questions (questions 23--45), and multiple-choice questions (questions 46--50).

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What to Do When Car Coolant Is Insufficient?

When the car coolant is insufficient, it should be appropriately replenished. Insufficient coolant cannot effectively cool the engine, which may accelerate engine wear in mild cases and potentially lead to engine burnout in severe cases. Below is a partial introduction to coolants: 1. Alcohol-based coolant: Uses ethanol (commonly known as alcohol) as an antifreeze. It is inexpensive, has good fluidity, and is simple to prepare, but it has a low boiling point, is prone to evaporation, has an easily elevated freezing point, and is flammable. It is gradually being phased out. 2. Glycerin-based coolant: Has a high boiling point, low volatility, is non-flammable, non-toxic, and has low corrosiveness, but it is less effective at lowering the freezing point and is costly. Only a few Nordic countries still use it.

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What are the main violations captured at traffic enforcement cameras?

Violations captured by traffic cameras include: running red lights, not driving in designated lanes, driving in the wrong direction, violating prohibitive road markings, making U-turns or left turns where prohibited, drivers not wearing seat belts as required, vehicles illegally using dedicated lanes, and large trucks entering restricted zones. Driving tips: 1. Slow down when approaching signalized intersections, maintain a safe braking distance, and avoid speeding up when the yellow light flashes. 2. Choose the correct lane. When approaching a signal-controlled intersection with designated lanes, enter the appropriate lane based on your intended direction. Do not go straight in a turning lane or turn in a straight lane. 3. Plan your route wisely. Before entering an intersection, observe the directional signs and lane markings to plan your route properly, and avoid crossing single or double solid lines at intersections.

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What causes pressure loss in the right rear tire?

Right rear tire pressure is abnormal and requires calibration. Here is relevant information: Tire Pressure: Tire pressure monitoring can include two types, direct and indirect. Direct systems are more expensive but provide more accurate monitoring results. Direct tire pressure monitoring uses sensors installed inside the tires to measure tire pressure, then transmits the information to the dashboard via a wireless transmitter. When the tire pressure is too low or too high, it automatically alerts and displays the pressure value. Direct tire pressure monitoring is more expensive but more precise. Tires: Car tires are one of the most important components of a vehicle, directly contacting the road surface and working with the suspension system to absorb shocks during driving, ensuring good ride comfort and smoothness. They also maintain strong traction between the wheels and the road, improving the vehicle's traction, braking, and off-road capability. Additionally, they bear the weight of the car, making their role increasingly recognized as crucial.

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Where Are the Side Airbags Located in a Car?

Car side airbags are safety airbags installed on the outer side of the car seats. Their function is to deploy when the vehicle is subjected to a side impact, protecting the passengers' sides and reducing injuries caused by the collision. Below is a detailed introduction to side airbags: 1. Side airbags are further divided into front side airbags and rear side airbags. Both front and rear side airbags are positioned on the side of the car seats near the windows. Typically, there are seven sensors in the car. When the sensors detect a side impact, the airbags will automatically deploy to protect the safety of the driver or front passenger. 2. The airbag system mainly consists of components such as sensors, a microprocessor, a gas generator, and the airbag itself. The sensors and microprocessor are used to assess the severity of the collision and transmit signals. The gas generator, upon receiving the signal, ignites solid fuel to produce gas that inflates the airbag, causing it to rapidly expand. The airbag capacity is approximately (50-90) liters.

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Can a 48V be upgraded to 72V without changing the motor?

No, if the original battery of an electric vehicle is 48V, adding two more batteries to make it 72V will definitely require replacing the controller and the motor. Without changing the controller, it won't function, and if the motor isn't replaced, the coils will burn out. 1. If the "motor is not replaced" and remains at 48V, under 72V, the load current will surge due to overvoltage, and the excessive current will burn out the controller. At the same time, the 48V motor will also be damaged by the overvoltage. 2. The "rated operating voltage" of the motor is crucial and is a necessary condition for the safe operation of the motor. For example, the rated operating voltage of a household air conditioner is 220V, and arbitrarily increasing the voltage is clearly unwise.

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How to Identify Battery Model Numbers?

Are all questions in Subject 4 multiple-choice?

What to Do When Car Coolant Is Insufficient?

What are the main violations captured at traffic enforcement cameras?

What causes pressure loss in the right rear tire?

Where Are the Side Airbags Located in a Car?

Can a 48V be upgraded to 72V without changing the motor?

Is it necessary to clean carbon deposits in the cylinder?

What are the rules for right turns at red lights?

How long can a vehicle be parked without turning off the engine?

What brand and model are the tires on the Buick Envision?