Comment by 01100011
9 hours ago
An aftermarket head unit connects to the CAN bus? The aftermarket head unit I installed certainly doesn't. Are you sure what you are saying, which is true for OEM units, applies to aftermarket ones?
9 hours ago
An aftermarket head unit connects to the CAN bus? The aftermarket head unit I installed certainly doesn't. Are you sure what you are saying, which is true for OEM units, applies to aftermarket ones?
The expensive ones do so you get more of an OEM infotainment experience. I guess you could potentially cause a crash over the CAN bus but there's a very small overlap between cars that allow you to swap out headunits and cars that can be controlled enough over CAN to cause a crash. Other than commercial vehicles, I don't think there are any new cars that have DIN stereos anymore.
Can't vouch for all car architectures, but in most cases the head unit is QM and safety domains are usually segmented from each other. So even if the head unit talks CAN (it needs to get car data somehow) it will only communicate with the rest of the car through a gateway that will not allow it to take any dangerous actions.
Mine does. Its dashboard shows fuel level and a bunch of other things and I can bring up a speedometer/rpm app.
I believe the connection exists because the steering wheel buttons/iDrive talk to the original head unit over CAN.
That’s wild, I’ve never run across a head unit that had me connect OBD2. I think I would just ignore that bit of the install instructions.
> speedometer/rpm
This is available on standard OBD-II. Maybe, it is accessible over CAN?
My OBD-II connector has CAN-C (500kbit) and CAN-B (50kbit) - I use CAN-B primarily because I can control windows, doors, etc + get the speed & rpm.
Many do - the one I was looking at for my vehicle in particular uses it to restore the steering wheel controls (which are broadcast over the CAN-B low speed bus)