What are the reasons for a car suddenly losing power?

[MacJeffrey]

The reasons for a car suddenly losing power are: 1. Battery depletion; 2. Circuit failure; 3. Generator malfunction. Methods for battery maintenance include: 1. After turning off the engine, avoid listening to music or using other electrical devices for extended periods; 2. Disconnect the negative terminal of the battery when the car is not in use for a long time; 3. Check whether the battery is securely fixed in the car and whether there are any impacts on the surface of the casing; 4. Check whether the battery cables are securely connected and whether there is dust in the exhaust vents; 5. Use the battery's inspection window to check the charging status and quality condition. The functions of the battery include: 1. Providing a strong starting current to the starter when starting the engine; 2. Assisting the generator in supplying power to electrical devices when the generator is overloaded; 3. Supplying power to electrical devices when the engine is idling.

[JuliannaFitz]

I've encountered sudden power loss in my car several times, mostly caused by battery issues. An aging battery or loose terminals can cause an immediate power cut-off. For instance, last winter when I was driving long-distance, the battery died without charging and the engine stalled suddenly, which scared me - I immediately turned on the hazard lights and pulled over to check. Alternator failure is also common; it charges the battery while the engine runs, and if it breaks, the current gets cut off - you'll need a multimeter to test the voltage. Blown fuses or short circuits happen frequently too, which you can troubleshoot yourself, but for safety, always keep emergency lights and jumper cables in the car. During regular maintenance, have your mechanic check these components, especially before cold weather, to save yourself a lot of trouble.

[WillowLynn]

When I first learned car repair, dealing with power loss was a real hassle, but I figured it out through trial and error. Most of the time, it's just a blown fuse—locate the corresponding position in the fuse box under the dashboard and replace it with a new one, which is low-cost. Rusty or loose battery terminals are also common; just clean them with sandpaper and tighten them. To test the alternator, use a voltmeter: above 12V with the key in the first position is normal, but if it's below 9V, it's faulty. Starter motor issues can prevent the car from starting—try giving it a light tap before attempting to start again. Basic tools like screwdrivers and a multimeter are all you need. Regular dust cleaning and inspections save money and give a sense of achievement. I recommend beginners watch videos to learn simple maintenance to avoid getting ripped off outside.

[MacCecilia]

On the way to take the kids to school, the car suddenly lost power—truly distressing. The engine stopped, and the car couldn't move. Usually, it's due to a dead battery or loose connection wires, possibly a faulty alternator failing to charge. At that moment, I immediately turned on the hazard lights, pulled over to ensure safety, and called for a tow truck or asked a friend for help. I always teach my kids to stay calm and keep emergency lights and a power bank in the car. It's recommended to have the battery life and wiring checked every six months to avoid unexpected delays. Safety first—develop the habit of checking dashboard lights before starting the car.

[OKing]

Vehicle power failure is mostly caused by electrical system issues, such as the alternator not generating electricity, excessive battery internal resistance, or main relay failure. Ignition switch problems or circuit short circuits often lead to stalling. During inspection, first check the battery voltage; if it's normal, then see if there's current at the alternator output. Replace aged parts promptly to avoid breaking down on the road. I recommend conducting more circuit tests during annual maintenance. Professionals can diagnose the root cause with a simple test, and even for those with strong hands-on skills, it only takes half an hour. Don't skimp on that little expense.