[ProjectProdegy27]

I am currently in the design phase of a potential EV build and want to get everything relatively planned so that I have a good idea of how to assess the whole thing when the time comes. I just want to get some recommendations on what options there are to power door locks(and other small functions like power mirrors or power windows). I understand that I could buy a conversion that was intended to be wired up while an I.C.E. was in the car but if a conversion has been done, say a Tesla swap with Large Rear Drive Unit and 16 battery modules, would there need to be any change or how would I need to wire it up so that the actuators and such function properly? I understand this may seem elementary to some who have already started EV conversions or have experience but I still am a university student who has a couple more years of university and payments to make before I can truly start it, so just want to expand my knowledge and see what I can learn from anyone willing to help.

 

[MattsAwesomeStuff]

It depends on the vehicle.

Some vehicles are going to have a lot of brains that get twitchy when everything's disconnected.

On an older vehicle, you just rip out the engine and that's that. All the rest of the electronics work just fine. They're largely independent, just physical switches that activate motors, nothing's changed.

 

[ProjectProdegy27]

Am I correct to assume that I would need a separate 12V Battery apart from the main battery pack in order to not overload the electronics connected?

 

[MattsAwesomeStuff]

Am I correct to assume that I would need a separate 12V Battery apart from the main battery pack in order to not overload the electronics connected?

You are absolutely not going to be running your 12v system from hundreds of volts, correct.

You either leave the 12v right where it was, or you replace it with a smaller one (no need to start an engine, all you need is some reserve capacity for safety). Then you use a DC-DC converter to step down from the pack voltage to 12v that runs the 12v system and keeps the battery topped up.

 

[P.S.Mangelsdorf]

Am I correct to assume that I would need a separate 12V Battery apart from the main battery pack in order to not overload the electronics connected?

Even production EVs use a standard 12V system for most of the car. Typically only the drive unit, and occasionally AC compressor or power steering pump will actually use the high voltage.

You'll need a dc-dc converter to keep it charged off of the HV pack (in place of an ICE's alternator).

If you're converting a classic car that had manual windows, doors, etc, there are a wide variety of kits out there for adding features. First step is determining if the car was available from the factory with that item, as reproduction harness are often available. If not, many street rod suppliers provide options for you to chose from.

One other note, if you're converting an older (pre 1950s) classic car, the existing wiring may be 6v rather than 12v.