This is what I did to power the Arduino which I used in my engine start button project. It’s a simple and cheap way to power an Arduino in a car. This will requires some basic soldering skills.
Step 1
But a simple USB charger – the kind that plugs into your car’s power outlet. They usually cost ~$2-5(USD). You can probably find them at most convenience stores, or maybe a box store of your choice.
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