Hacker News Reader

Comment by RajT88 | Hacker News Reader

Just FYI - you can replace your head unit even on newer cars. There's a bustling aftermarket industry for this kind of stuff:

https://www.belsee.com/android-car-radio/hyundai-radio.html

This way - your data gets abused by the Chinese government instead of Hyundai!

(I kid, sort of, but these head units let you exert more control over your car, as they often ship rooted, or can be rooted)

If you DIY install the head unit, you can often completely pay for the head unit and have cash left over by selling your old head unit to someone who needs one. (Lots of people need a stock head unit, because theirs got stolen, or they bought a salvage title without a head unit, or whatever).

View on HN

I'd pay to just not have one, but I'm not even sure that's possible any more. I'm really not looking forward to when I'm forced to buy a new car - few things make me more mad than smartphone tech with universally slow and terrible UX, duck-taped onto machines, let alone dangerous machines.

> I'd pay to just not have one, but I'm not even sure that's possible any more.

Yeah, some stuff makes you go through the head unit on some machines. Any replacement head unit would have to implement the same controls somehow.

Wealthy will be the person who makes a generic 2 DIN head unit, where you have physical buttons which you can map to various CANBus messages.

I'm working on a generic device that sends canbus messages, that can have inputs such as potentiometer, push buttons, toggle switches, and rotary encoders. My end goal is to have real hvac controls on my Tesla, but I'd like to abstract the device as much as possible. Fun project, and most of the hardware necessary is already out there.

I've been hoping somebody would do that.

I have a only half-joking business idea to build high-quality physical controls for all of the crap touchscreen shit being forced upon us. High-end ovens for example rarely now include physical controls so (I'm looking at you Miele) so I would like an aftermarket thing that sticks on to the outside of it. Maybe even directly over the touch screen. Actually, hmm, that's a good idea. Maybe we need a device that is the size of various standard touch screens that can read the contents of the screen, interpret them, and then have some sort of way to do capacitance touch on the screen. All of this of course hidden from the user who just wants a damned analog knob.

That is super badass and I'd love to have something like that.

Does the factory display/controls use the canbus to do their work? How much stuff can you reasonably do through that? Do you know if it varies between manufacturers?

The problem is, there's not just one "CAN/LIN bus." There are probably a dozen different segments. One device attached to one segment can only talk to the upstream gateway and whatever peripherals are on that bus segment.

Of course this isn't a problem per se, it's good design -- but it has the side effect of making it harder to hack your own car through a single point of entry other than the main OBD2 port, which is connected to the top-level gateway.

> it has the side effect of making it harder to hack your own car through a single point of entry other than the main OBD2 port

Thanks! Do you know by chance if the OBD2 port can talk to/control everything? Would that be a good entrypoint?

In my own VW group cars, the CAN bus pins on the OBD2 port do have access to everything. I don't know if that's true for all/most cars in general, though.

Awesome! I demand links! Give me a GitHub I can watch and contribute too. My soldering iron is already hot! LFG!

The dream:

https://www.amazon.ca/Honeywell-CT87N1001-Round-Manual-Therm...

You're touching on a real opportunity, going down a open hardware canbus-dash computer.

This is one of those rare 'holy shit do this right now' kind of things.

Seriously. I have zero use for a touch screen in a car.

Maps? When I drive I look at... the road. If I need directions, google maps can tell me to turn left etc by voice commands.

Eh I'm anti touch screen controls, but as a motorcyclist driving in a foreign country relying on voice directions I need the visual input too. There's a big difference between audio only directions for a spaghetti junction and being able to glance at the visual and combine that with the audio.

You take your eyes off the road all the time doing head checks (blind spot checks), so long as you're not staring at the map I think the benefit of being sure about where you're going is safer

My Ioniq 5 (ironically, a Hyundai...) puts turn by turn directions on the HUD, if you want--eyes stay on the road, but you get full visual feedback. To me that's the best of both worlds. Downside is it only works with the on-board nav and not CarPlay/AA.

Sounds like google maps, am i right? Almost any other navigation product will do a combination of zooming in and displaying actual road signs with clearly marked intersections etc. Maps is useless without also turning on voice.

I don't think I could live without it anymore, but I have a really tight parking situation at home and the parking sensors that are exposed through the head unit are really useful. Not to mention navigation and all that stuff. These features are really considered standard now by most (but definitely not all) people.

I had that in a car from 2008 or so. Camera feed switched on when you were reversing, but no touch screen.

Radar parking sensor are very useful. Not sure if you had that in 2008.

In my car, this all comes in via the head unit. Critical driving stuff isn't allowed to be in the head unit (wisely), parking display doesn't come up as critical although the sensors are technically available even if the head unit is fried, which I found out when my head unit failed (car was still drivable, but many nice things gone).

It wasn't radar, it was just a camera feed that activated when I put it in reverse.

...people actually use voice commands? I've not used them in any GPS for like 10+ years nor do I know anyone who has audible navigation enabled.

what's the alternative - looking at a screen? I want to concentrate on driving.

I personally find that having to pay attention to visual prompts(turn right in 1km) makes me far more focused on the road than listening to the prompts, which can come without any warning and don't allow you to appreciate what is going to happen with enough warning. I usually glance and see that in 10km I'm taking the 3rd exit at the roundabout, then I know for next 10km I can focus entirely at the road, take 3rd exit at the roundabout and then will glance for next instruction again.

In previous discussions about how shitty touchscreen car interfaces are, people have been mentioning that new cars must provide a backup camera. I'd like to have just the camera, but why would manufacturers stop there when they can ship spyware as well? The screen is the expensive part.

Touch screens are actually incredibly cheap off the shelf components compared to all of the bespoke physical buttons and dials required to kit out a car.

Both of my older vehicles have aftermarket head units and I absolutely love them. It's definitely a lot of faff to get them in and working, but a few hundred dollars and some frustrating weekends beats buying an entire new car loaded to the gills with spyware that wants a subscription fee for it's heated seats.

And you don't need to worry about the chinese government if you just never connect the things to the internet, which I never do. They are a conveyance for CarPlay access and nothing more.

It's tricky for some cars. Things like non-standard sizes for the opening. Important functionality baked into the head unit (Volvo, for example, has paths to configure some safety options, trip/mpg display, etc). Integration for steering wheel controls, rear displays, backup cameras. And more that I'm missing off the top of my head.

For some vehicles, some of the above have options to tie in with a 3rd party setup, others don't.

My current head unit for (admittedly a 10 year old VW) does all of those things.

Backup camera, steering wheel buttons, MPG, fuel level, low tire warnings...

It's actually really impressive for for $190 I spent on it.

The only thing which it disabled when I replaced the head unit was the built-in handsfree bluetooth stuff. It all goes through the stereo now (and doesn't work that great). YMMV on these aftermarket head units.

A lot of the stock head units look like weird sizes, but it's really just trim on the front of it looking highly custom. Aftermarket units sometimes (often?) come with matching trim pieces to make it look OEM.

Sure. Just saying there are some setups that either don't work, or don't work completely. Steering wheel controls is a good example. You can go to the product site for one of those expensive integration units, and their "product fit guide" will show you it works with some cars and not others.

And, yes, some cars can fit a head unit even though the opening looks odd. Others can't, at all. Volvo has several cars in that category.

In some cars this means you are unable to hear the beeping of the proximity sensors. I would guess that you'd also lose any 360° camera views as well.

It's worth mentioning these screens are not crash tested and can become shards of glass in an accident.

Reply on news.ycombinator.com