[elcritch]

Actually there’s two paths: first the traditional path of different unique wiring harnesses and various signals with unique connectors, or second a common power and coms bus design.

If the Cybertrucks electrical ethos is followed by others there’s only 48V and Ethernet. Ethernet doesn’t care or fry if plugged into a wrong port. Any complex wiring can be done inside a part or component as needed, but the interface is one of a few options.

Let’s say the window motor is plugged into the power and not the switched motor plug. As long as it’s a 48V motor it’ll just turn but not fry. You just unplug it and reconnect it.

IMHO industrial everything should become 48V Ethernet. Just like for gadgets usb-c rules the roost.

[michaelt]

> If the Cybertrucks electrical ethos is followed by others there’s only 48V and Ethernet.

I'm looking at the electrical schematic [1] and 'eth' appears 107 times while 'CAN' appears 805 times.

And if you think about it, you probably don't want your brake-by-wire system to share a bus with your sound system and your trunk latch for obvious reasons.

[1] https://service.tesla.com/docs/Cybertruck/ElectricalReferenc...

[elcritch]

Cool, thanks! It looks like the cybertruck does extensively use CAN still. Tesla only talks up Ethernet.

Makes sense, though I’m a bit bummed.

> And if you think about it, you probably don't want your brake-by-wire system to share a bus with your sound system and your trunk latch for obvious reasons.

Sharing a bus for those two wouldn’t make sense. However Ethernet topology wouldn’t preclude having those on separate buses and linked via switches.

Though that’d pose problems with my view above about plugging anything in anywhere. Though it’s really more of a philosophical goal. ;)

[HeyLaughingBoy]

> However Ethernet topology wouldn’t preclude having those on separate buses and linked via switches

The topology might not care, but someone designing a trunk latch that communicates via Ethernet might get a visit from an annoyed representative from Value Engineering.

[elcritch]

Haha touché. However unintuitive as it may seem an ethernet based trunk latch could be overall cheaper from a system level than a straight relay based system or even CAN system.

Especially with the newer two wire ethernet with power via 10BASE-T1S. The connector likely costs more than the ethernet chip, and microprocessors can be had for nickels. So at large manufacturing scale it could easily cost less to share a single ethernet and power line and save on wiring, connector complexity, etc.

[HeyLaughingBoy]

If costs have dropped to the point that Ethernet is less expensive than LIN, it would definitely be a surprise.

[aeonik]

What are the obvious reasons?

[solarkraft]

Different quality of service requirements. The infotainment system is complex and it failing is just annoying while the brake failing could mean death.

[Glawen]

Denial of service of the bus due to a bug or electrical malfunction

[aeonik]

I thought the discussion was on context of CAN vs Ethernet.

These two are still vulnerabilities with Ethernet.

[Aloisius]

Even Cybertrucks aren't purely 48V and ethernet.

There's a high voltage (800V) rail for high current devices like the AC compressor. There's redundant CAN for communication with things like the motors. There's a host of 12V, 16V, 5V components (door locks, lights, seat motors, etc.).

They did switch many components to 48V, but not literally everything.