What time does the Subject 3 exam start?

How to Measure Battery Voltage?

Measuring battery voltage involves the following steps: 1. Select the appropriate range on the multimeter; 2. Connect the multimeter in series within the circuit; 3. Ensure the red probe allows current to flow in, while the black probe allows current to flow out; 4. Always connect an electrical appliance in the circuit, and never connect the ammeter directly to both ends of the battery. Battery voltage is typically 12V or 24V. Most household gasoline-engine cars use a 12V battery, while diesel engines, which operate differently from gasoline engines, require higher voltage and thus often use a 24V battery. The voltage of a 12V battery is not fixed and is usually slightly higher.

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What are the differences between China 5 and China 6 vehicle models?

The differences between China 5 and China 6 emission standards are as follows: Different emission standards: The China 6 emission standard is more than 30% stricter than China 5. Excluding the influence of working conditions and testing, the carbon monoxide emissions of gasoline vehicles are reduced by 50%, the total hydrocarbon and non-methane hydrocarbon emissions are reduced by 50%, and nitrogen oxide emissions are reduced by 42%. Different implementation times: The China 5 standard was implemented nationwide on January 1, 2017, as the fifth stage of national motor vehicle emission standards. China 6 was implemented on July 1, 2019. Different principles: During the China 5 phase, diesel and gasoline vehicles had different emission standards, but China 6 adopts a fuel-neutral principle, meaning that regardless of the fuel type, the emission limits are the same. Different issuing departments: The China 5 standard was issued by the Ministry of Environmental Protection, while the China 6 standard was issued by the Ministry of Environmental Protection and the General Administration of Quality Supervision, Inspection, and Quarantine. Different letter representations: China 5 is represented by 'V', while China 6 is represented by 'VI'. Different monitoring requirements for plug-in hybrid electric vehicles: Compared to China 5, China 6 has improved monitoring requirements for plug-in hybrid electric vehicles, including energy storage systems, thermal management systems, brake regeneration, drive motors, generators, and other regulatory aspects. The China 5 standard limits are as follows: Gasoline vehicles must not emit more than 1000 mg of carbon monoxide per kilometer driven. Gasoline vehicles must not emit more than 68 mg of non-methane hydrocarbons per kilometer driven. Gasoline vehicles must not emit more than 60 mg of nitrogen oxides per kilometer driven. Gasoline vehicles must not emit more than 4.5 mg of PM fine particles per kilometer driven. China 6 has two standards: China 6a and China 6b, which are as follows: China 6a standard limits: Gasoline vehicles must not emit more than 700 mg of carbon monoxide per kilometer driven. Gasoline vehicles must not emit more than 68 mg of non-methane hydrocarbons per kilometer driven. Gasoline vehicles must not emit more than 60 mg of nitrogen oxides per kilometer driven. Gasoline vehicles must not emit more than 4.5 mg of PM fine particles per kilometer driven. China 6b standard limits: Gasoline vehicles must not emit more than 500 mg of carbon monoxide per kilometer driven. Gasoline vehicles must not emit more than 35 mg of non-methane hydrocarbons per kilometer driven. Gasoline vehicles must not emit more than 35 mg of nitrogen oxides per kilometer driven. Gasoline vehicles must not emit more than 3 mg of PM fine particles per kilometer driven. Affected by the China 6 emission policy, although China 5 vehicles are not currently restricted in normal use, with no driving or license plate restrictions, the resale value of these vehicles will be significantly impacted. For car owners, if they purchase a truck on loan for cargo transport, the depreciation of the vehicle after paying off the loan is equivalent to the net profit earned by the owner during that period. A higher residual value means the owner earns more. Therefore, from this perspective, China 6 vehicles, which have a longer service life and more road rights, are more advantageous.

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How to Test the Condition of an Ignition Coil

Methods for testing the condition of an ignition coil: Turn on the ignition switch, confirm that the low-voltage circuit is functioning properly, then pull out the high-voltage wire from the center of the distributor cap, positioning it 3 to 5 millimeters away from the engine block. Use a screwdriver to repeatedly open and close the breaker points. If a blue-white spark jumps between the high-voltage wire and the engine block accompanied by a crisp sound, it indicates that the ignition coil is in good condition. If there is no spark and the high-voltage wire is confirmed to be functioning properly, it suggests that the ignition coil has failed. During engine operation, the condition of the ignition coil can also be judged by temperature: a slightly warm coil is in good condition, while a scalding hot one indicates a faulty or damaged ignition coil. Additionally, installing the suspected ignition coil on a gasoline engine with a fully functional ignition system for a spark test can also help determine its condition.

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What is the method for checking engine oil pressure?

Engine oil pressure checking method: 1. Unplug the wiring harness connector of the oil pressure sensor, remove the oil pressure sensor, and screw the hose connector of the oil pressure gauge into the threaded hole where the oil pressure sensor was installed; 2. Place the oil pressure gauge in a location where it will not come into contact with rotating or high-temperature engine components; 3. Start the engine and check for oil leaks at the oil pressure gauge connection; 4. Run the engine until it reaches normal operating temperature. Only when the oil pressure value is within the normal range can the oil be ensured to be delivered to all parts of the engine. Pressure that is too high or too low can affect normal operation and even cause damage to the engine.

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How to Determine if the Battery Has Power?

Methods to determine if the battery has power: 1. If the car struggles to start, it is likely due to a weak battery; 2. The battery warning light—if it stays on, it indicates the car battery is running low and needs charging promptly; 3. Press the car horn—if the sound is weaker than usual, it may be due to a weak battery. The car headlights may also be affected, appearing dimmer. If the battery is severely depleted to the point where the car won't start, the owner will need to jump-start the generator.

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What are the methods to identify an odometer-tampered car?

Methods to identify an odometer-tampered car include: 1. Check the vehicle's maintenance records; 2. Use a diagnostic computer to read the transmission mileage; 3. Inspect the aging and wear of the interior; 4. Examine the wear on brake discs, brake pads, and tires. If a buyer encounters an odometer-tampered car, it is advised not to purchase it. Odometer-tampered cars are often sold at higher prices that do not reflect the car's actual value, deceiving buyers. When selling a used car, to fetch a higher price, some may reduce the mileage to mislead buyers into thinking the car has less wear, thus purchasing the used car at an inflated price.

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What time does the Subject 3 exam start?

How to Measure Battery Voltage?

What are the differences between China 5 and China 6 vehicle models?

How to Test the Condition of an Ignition Coil

What is the method for checking engine oil pressure?

How to Determine if the Battery Has Power?

What are the methods to identify an odometer-tampered car?

How to conduct the annual inspection for a new car in its second year?

What types of vehicles can a C2 driver's license drive?

How to Check the Vehicle Engine Number?

How to Measure the Crankshaft Position Sensor?