Q: Does the alternator and starter work together

asked by on September 08, 2017

Does the alternator work with the starter in a car?

My car has 90000 miles.
My car has an automatic transmission.

No, they do not work together. The starter motor relies solely on stored energy in the battery to function. It is only after the engine actually starts and runs that the alternator can provide power to vehicle systems as well as re-charge the battery. The starter uses a lot of energy to turn over the engine. Once the engine does start, then the alternator generates electricity to re-charge the battery. The alternator also works with the battery as the car runs to supply power to all the vehicle systems. If the alternator dies, if the battery is fully charged at that time, the car will still run for a short while, the duration depending on how much power the vehicle requires. Never disconnect the battery from a vehicle while the engine is on. Disconnection will cause a voltage excursion that can potentially destroy sensitive electronics on the vehicle. ALL service performed on the alternator, battery, starter and any other electrical component of the vehicle must be performed when the vehicle is off and often with the battery disconnected. There are a million other cautions when it comes to working around the alternator and starter. Please, for your own safety, and to prevent damage to your vehicle, if you need assistance with these components, request the services of a competent, well trained and certified mechanic such as you will find at YourMechanic. If you desire to request service, please review the hundreds of services listed at the YourMechanic website and simply click on the services of interest. There is tons of information there about car and trucks! If you have further questions or concerns, do not hesitate to re-contact YourMechanic because we want you to make the most of your repair dollars and help you to get the best possible results.

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