Are there any hints for multiple-choice questions in the Subject 4 exam?

What are the common sensor failures in Audi vehicles?

Audi vehicle sensor failures include mass air flow sensor failure, coolant temperature sensor failure, and front oxygen sensor failure. Specific failures are as follows: Mass Air Flow Sensor Failure: If the mass air flow sensor or its circuit malfunctions, the ECU cannot receive accurate intake air volume signals, resulting in either excessively rich or lean air-fuel mixtures. This leads to incomplete combustion, causing unstable engine idle, increased fuel consumption, poor acceleration, and worsened exhaust emissions. Coolant Temperature Sensor Failure: If the coolant temperature sensor fails or its circuit has issues, the ECU cannot obtain correct coolant temperature signals, making precise fuel injection control impossible. This often results in difficult cold starts, acceleration problems, and severe vibrations during cold starts. Front Oxygen Sensor Failure: If the front oxygen sensor fails, the ECU cannot precisely control the air-fuel ratio, leading to various symptoms of incomplete combustion such as unstable idle, misfires, and surging vibrations.

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What are the dimensions of the Avalon?

The exterior dimensions of the Avalon are: length 4975mm x width 1850mm x height 1450mm, with a wheelbase of 2870mm. The Avalon is positioned as a mid-size sedan. Here is more information about the Avalon: 1. The Avalon is an entry-level luxury sedan with two different styling designs. The hybrid version features a multi-bar grille, while the gasoline version has a black mesh pattern. The headlights are irregular quadrilaterals. 2. For the interior, it comes with a 9-inch multimedia touch screen, and the multifunction steering wheel is wrapped in genuine leather. The instrument panel has traditional analog gauges on both sides, with a 7-inch HUD display in the center. Behind the gear shift are buttons for driving mode selection and an electronic parking brake. 3. In terms of features, it includes safety technologies such as Rear Cross-Traffic Braking, a Panoramic View Monitor with alert function, and Intelligent Clearance Sonar. It is equipped with Toyota's Entune 3.0 Plus infotainment system, Remote Connect technology, Scout GPS Link app, wireless smartphone charging, and 2G Wi-Fi Connect.

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How to Deal with the HDC Warning Light?

HDC is the Hill Descent Control system warning light. If the warning light is on, it is necessary to go to a 4S shop for repair. The Hill Descent Control system allows the driver to smoothly pass steep downhill sections without fully controlling the brake pedal. As needed, the braking device automatically controls each wheel to move forward slightly faster than walking speed, allowing the driver to focus entirely on steering. Here is some related information about HDC: 1. When HDC is set, after the vehicle enters a steep slope, the engine brake itself can provide a considerable degree of deceleration effect without the risk of tire lock-up. When the steep slope is too large and the engine brake is insufficient to maintain the speed limit, HDC can use the ABS system to initiate brake point release when necessary, reducing the gradually increasing speed to maintain a stable and safe downhill speed. 2. If the driver must steer to avoid obstacles during the steep descent, the HDC system will also detect this and further reduce the speed limit to 6.4 km/h to ensure complete control of the vehicle. After the HDC button is set, the driver must release all pedals, including the throttle, brake, and clutch of a manual transmission car, for it to take effect.

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Can a small spare tire carrier be installed on the Prado after purchase?

The Prado can be equipped with a small spare tire carrier, also known as a rear-mounted spare tire, but it is not recommended as it may cause rattling noises over time. The regulations and precautions for vehicle modifications are as follows: Vehicle modification regulations: The Prado can be modified with a rear-mounted spare tire, but after the modification, the vehicle's appearance will change, requiring the owner to apply for a modification registration at the vehicle management office. According to Article 10 of the "Motor Vehicle Registration Regulations," registered motor vehicles must apply for modification registration under the following circumstances: changes to the vehicle's color; replacement of the engine; replacement of the body or frame; replacement of the entire vehicle due to quality issues; change of use from commercial to non-commercial or vice versa; or when the owner's residence moves in or out of the jurisdiction of the vehicle management office. Precautions for vehicle modifications: The vehicle owner must apply for modification registration within ten days after the modification. Before applying for the modification, the owner must resolve any traffic violations or accidents related to the vehicle.

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What Causes Body Shaking at Speeds of 80 to 90 km/h?

This situation occurs due to issues with the wheel dynamic balance. When this happens, you should visit a professional institution to perform a dynamic balance test for each wheel. After every tire replacement or repair, it is essential to conduct a dynamic balance test for each wheel to prevent abnormal vibrations during high-speed driving. More details are as follows: 1. If abnormal wheel vibrations occur during high-speed driving, the vehicle body will also experience abnormal shaking, which affects driving stability, handling, and ride comfort. 2. Tires are a crucial component of a vehicle, being the only part in contact with the ground. They are vital for driving stability and safety. As rubber products, tires age over time with prolonged use, necessitating regular replacement. 3. Under normal conditions, tires can be used for four years after installation. It is recommended to replace them every four years. When purchasing new tires, always check the production date, as tires have a shelf life. Normally, unused tires have a shelf life of three years. Avoid purchasing tires that have been in storage for over three years. 4. During regular vehicle use, frequently check the tire pressure, as it is critical for tire performance. Tire pressure should neither be too high nor too low.

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When removing a car battery, should the positive or negative terminal be disconnected first?

Disconnect the negative terminal first when removing the battery. Here are the relevant steps for battery removal: 1. Before replacing the battery, check if it is completely depleted. If the battery is cracked, replace it immediately. If not, first inspect both terminals of the battery. Sometimes, sulfate formation can corrode the battery terminals. Try scrubbing them with a brush dipped in a mixture of baking soda and water. The battery might still be usable. 2. Turn off the engine before replacement. Carefully loosen the battery screw connected to the negative terminal with a wrench and remove the cable clamp from the terminal. Then, remove the positive terminal in the same manner. Firmly grasp the battery and remove it from the car. After removal, take a moment to clean the clamps and battery tray with soda water. 3. Installation: Carefully place the new battery in the battery tray. Ensure the positive and negative terminals are correctly positioned, then secure the battery by tightening the bracket. Connect the positive terminal first, followed by the negative terminal. Finally, close the hood.

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Are there any hints for multiple-choice questions in the Subject 4 exam?

What are the common sensor failures in Audi vehicles?

What are the dimensions of the Avalon?

How to Deal with the HDC Warning Light?

Can a small spare tire carrier be installed on the Prado after purchase?

What Causes Body Shaking at Speeds of 80 to 90 km/h?

When removing a car battery, should the positive or negative terminal be disconnected first?

Is there a difference between the DPL and DKX engines?

Can the Driving School Help Cancel the Subject 2 Test?

What is the significance of Volkswagen's 2.0T low-power engine?

What is the compression ratio of the Mistra 1.8?