>> Those are the easy parts because all 3 run off of hydraulics and electricity. As long as they get power supplied to them, they all just work. Except the hea

>> Those are the easy parts because all 3 run off of hydraulics and electricity. As long as they get power supplied to them, they all just work. Except the heat in your car is transferred from the coolant running through your engine. Which is why the 'heat' in your car doesn't work until you've been driving it for a little bit. >> Brakes don't even need power, I believe, and can work purely mechanically. Brakes definitely need power. Have you even driven an older car without power brakes or steering? There's a reason they used to have much larger steering wheels in cars. And most of your brakes are hydraulic with vacuum assist. Turn your ignition off (in a large parking lot) and try to steer or brake your car! The brakes will work once or twice... You would need to add electric power steering to an older car. You can convert over a Volvo system, get an electric pump, or do it a few other ways. >> That's generally an issue with high labor costs and not the car industry in particular. I'm talking just parts. For example, you need a control pack from Ford which contains the ECU and wiring harness which is nearly two thousand dollars, and aftermarket systems aren't even cheaper. https://www.jegs.com/i/Ford+Performance/397/M-6017A504VB/10002/-1?gclid=CjwKCAjwiY6MBhBqEiwARFSCPlUefVYyyKqP9N61R6cohkjKNyFo_f1PqBCPV5El1cLN-kpLx0FmvhoCGskQAvD_BwE https://www.jegs.com/i/Ford+Performance/397/M-6017A504VB/100...