배터리 교환 수리 사례

2026. 8. 11. 작업

난이도 & 준비물

증상

Am posting here as this question seems to be considered off-topic on both the electronics and the Raspberry sister sites. Would like to install a carputer (Raspberry Pi), and am wondering about the minimal equipment needed to power it from the car. Have battery plus, battery minus/chassis ground, and ignition sense available. I understand a step-down converter (12V->5V) is not enough, since the power line may have up to 100V or so when the car starts (not sure about exact figure). If I want a stable 5V supply as long as the car engine is running, and 0V when it is not running, what is the simp

처리 내용

Most everything external of the ECU is going to be 12vdc (+/-2v). (NOTE: As @juhist points out, more and more cars are supporting 5vdc output to charge handheld devices through USB ports. 5vdc may already be available, but without knowing the specific car, there's be no way for us to help you with this.) The voltage doesn't spike unless there's unusual conditions like when a car is jumped incorrectly or other such nonsense. There are no 5vdc supplies available to the user. The only 5v source is located within the ECU and the step down on that is handled internally to the ECU. The easiest way to do what you want is to use a phone car charger with an add-on power outlet socket. This is something you could fit behind the dash in most any car. Hard wire the socket into a keyed power source, then hard wire the outlet end of the charger directly into the Raspberry Pi device. All of the wiring you could hide with out issue. A car charger should provide you with enough power conditioning to gi