What are the time requirements for the Subject 2 test items?

What Causes the Engine Fault Light to Illuminate Yellow?

The illumination of the yellow engine fault light is a warning, indicating that certain system parameters of the vehicle may have exceeded the set range. At this time, the vehicle can continue to drive, but some functions may be restricted. The engine fault light can also be red. When the red fault light illuminates, it means the vehicle must stop immediately, turn off the engine, and prohibit further driving while checking for the fault. There are mainly seven reasons for the engine fault light to illuminate: Sensor malfunction: The sensors mentioned here include coolant temperature, crankshaft position, air flow, intake temperature, oxygen sensors, etc. When these sensors are damaged, have poor contact, or signal interruption, the vehicle's ECU cannot accurately obtain engine data, causing the engine fault light to illuminate. Fuel or oil quality issues: If fuel or engine oil is not added as required by the manufacturer, it may cause engine wear, leading to the fault light illuminating. Poor mixture combustion: Poor mixture combustion can cause engine carbon buildup or knocking. When detected by the oxygen sensor and reported to the ECU, the fault light will illuminate as a warning. Spark plug failure, ignition coil failure, fuel pump failure, or fuel line blockage can all cause poor mixture combustion. Turbocharging issues: The intake turbocharging pipeline or turbocharger can also cause the engine fault light to illuminate. The most common issue is turbocharger damage, accompanied by symptoms such as oil leaks, high oil consumption, reduced power, metallic noises, or blue/black smoke from the exhaust. Intake issues: If there are problems with the vehicle's intake, it may lead to engine pipeline blockage, and in severe cases, the engine fault light will illuminate. A dirty air filter that is not cleaned regularly can cause intake problems. Exhaust issues: Exhaust faults can also cause the engine fault light to illuminate. The rear oxygen sensor, catalytic converter, exhaust camshaft, and bearing failures are common causes of exhaust problems, with the catalytic converter being the most frequent. Using leaded gasoline, lead or silicon-based lubricant additives, physical damage to the catalytic converter, or fuel supply system faults can easily cause catalytic converter issues. Anti-theft system malfunction: If the vehicle's electronic anti-theft system fails or the anti-theft controller does not match the engine electronic controller, the anti-theft system can prevent the engine from operating normally, and the engine fault light will illuminate. If the engine fault light illuminates, follow these steps: First, check if the engine is running normally and if there are any issues such as shaking or smoke. If so, avoid restarting the engine. Note: Do not restart the engine if the red light is on. If the engine can start, turn it off for 5-10 minutes, then without pressing the brake, press the start button once or turn the key halfway to the 'on' position without pressing the clutch. The vehicle will perform a self-check after powering on. Wait for 5-10 seconds and observe if the fault light on the dashboard turns off. If the fault light remains on, visit a service center as soon as possible. The service center can use a portable diagnostic tool to read the fault code, obtain fault information, and perform targeted repairs.

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Can New Energy Electric Vehicles Wade Through Water?

New energy electric vehicles can wade through water. Theoretically, electric vehicles have better wading capability than traditional fuel-powered vehicles. The entire power battery and motor can operate normally even when submerged in water, without worrying about water entering the engine and causing damage. Definition of New Energy Vehicles: New energy vehicles refer to vehicles that use unconventional vehicle fuels as power sources, integrating advanced technologies in vehicle power control and driving to form vehicles with advanced technical principles, new technologies, and new structures. Types of New Energy Vehicles: New energy vehicles include pure electric vehicles, extended-range electric vehicles, hybrid vehicles, fuel cell electric vehicles, hydrogen engine vehicles, etc.

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What Causes a Motorcycle to Cut Off Fuel at 6000 RPM?

Motorcycle cutting off fuel at 6000 RPM is basically a carburetor issue, such as problems with the carburetor's air-fuel mixture ratio, needle valve, fuel level, choke, etc., or improper adjustments, as well as the carburetor itself being faulty or incompatible with the motorcycle. The focus should be on inspecting and adjusting the carburetor, or replacing it. Motorcycle gradually slowing down and cutting off fuel: If a motorcycle gradually slows down and cuts off fuel while riding, with the engine slowly shutting off on its own and a noticeable loss of engine power before stalling, it is generally a fuel supply system malfunction. Engine cutting off fuel and stalling with noise: If the engine makes a loud "popping" sound during the fuel cutoff and stalling process, cannot be restarted after stalling, and the kickstarter lever feels very little compression, it can be determined that the cylinder head gasket has been burned through or the crankshaft oil seal is damaged.

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What does motorcycle CVT mean?

Motorcycle CVT (Continuously Variable Transmission) has no gears and uses an automatic centrifugal clutch. It changes the transmission ratio by adjusting the diameters of the front and rear pulleys. This type of transmission has no fixed steps and is entirely controlled by throttle, engine speed, and pulley diameter changes. Definition of stepped transmission: Automatic disengagement still means the clutch is in an automatic disengaged state, while stepped transmission incorporates gear shifting. This combination significantly improves working efficiency compared to scooter transmission forms, enhancing power while reducing fuel consumption, though it still has drawbacks. Definition of multi-speed transmission: This type of transmission still consists of a clutch and gear shifting, except that the clutch is no longer automatically disengaged but manually disengaged instead.

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Does a deformed car tire cause shaking when driving?

A deformed car tire will cause a sensation of up-and-down shaking and vibration when driving. If a car's tire becomes deformed or worn, it must be replaced immediately to prevent affecting the normal use of the vehicle and to ensure driving comfort. Wear Limit: When the tire wears to the wear limit indicator, there are small triangular patterns along the sidewall and the edge of the tread. Moving horizontally from any of these triangles to the tread pattern, you will notice small raised sections within the tread that are lower than the normal tread pattern. These are the safety indicators, and driving beyond this point means the tire should be replaced. Aging Degree: Check the tire's aging degree. If the tire has many cracks but they do not affect normal use, it can still be driven. However, if the crack depth exceeds three millimeters, the tire needs to be replaced. Tread Deformation or Bead Damage: Tires with tread deformation or bead damage, if driven while flat, can cause the sidewall to be crushed and damaged. Tires corroded by chemicals should not be used. Tire Repair: If a tire has been repaired more than three times, it is necessary to replace it with a new one.

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Can National VI Diesel Vehicles Operate Without Urea?

National VI diesel vehicles cannot operate without urea. With the country's increasing emphasis on environmental protection, vehicle urea has become an indispensable necessity for National V and VI heavy-duty diesel vehicles. Operating a diesel vehicle without urea not only subjects the owner to hefty fines but also leads to severe consequences that can affect the normal operation of the vehicle. The functions of adding urea to diesel vehicles include: Optimizing Engine Performance: Using urea in vehicles can optimize engine performance and fuel consumption, reducing diesel consumption by up to 6%, significantly lowering costs. Purification Effect: It serves a purification function by reacting with nitrogen oxides in the exhaust, reducing nitrogen oxide emissions. Vehicles are equipped with a dedicated urea tank where the urea is stored. As long as the vehicle is running, urea will be consumed, so it is essential to replenish it promptly.

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What are the time requirements for the Subject 2 test items?

What Causes the Engine Fault Light to Illuminate Yellow?

Can New Energy Electric Vehicles Wade Through Water?

What Causes a Motorcycle to Cut Off Fuel at 6000 RPM?

What does motorcycle CVT mean?

Does a deformed car tire cause shaking when driving?

Can National VI Diesel Vehicles Operate Without Urea?

Can the car cool without turning on the AC?

When is the appropriate time to use turn signals?

Does a new car need to undergo on-site inspection in its sixth year?

What does LO mean in car air conditioning?