I have some ideas for a rear facing camera, AI, and communication servers I would like to add to my car ( a 2006 ford focus). I can handle all of that set up, what I have no idea about is the power coming into the system via the wire harness where the stereo would have been. Are car stereos standardized in any way? what voltages, and currents would I have? I need about 7 watts, at 5vdc for the operation of a Raspberry Pi (small computer). If there is a +5V source, is that stable? (or should I build a noise filter, and anti hysteresis circuit protection?)
I am looking for detail on the power supply of a ford focus stereo adapter. I am not looking to retain the adapter to power the stereo.