Tablet Car Mount for Seat Altea

Hello, I have an Altea from 2006. After the radio started annoying me more and more, because it either just talked or played the same music over and over, I removed the radio and installed an Android tablet (Nexus 7) and amplifier instead. In addition to that, I got an OBD2 Bluetooth dongle, and now my tablet can display things like fuel consumption using the Torque software. However, I don't really know much about cars. Does the OBD2 connection also provide information about whether a button on the steering wheel remote control has been pressed? Or do I need to somehow tap into the CAN bus behind the radio, and how would that be best done?
It would be great if I could get this information onto the tablet so that I can use the buttons to, for example, skip to the next song.
My plan B would be to tap directly into the wires from the steering wheel somewhere and create a Bluetooth controller for it, programming it myself. Do you think that's feasible? Also, do the wires for each button come out separately?
I'm looking forward to help and creative ideas,, Wust.

You won't be able to directly read the steering wheel control buttons through OBD, even if the signals are present on the CAN bus at the OBD port. This is because they are not used for diagnostic purposes and therefore cannot be accessed via diagnostics.

You either need to read the signals from the car's CAN bus using a microcontroller, or purchase dedicated adapters for the car radio and connect those signals to the tablet accordingly.

Hello,
I just bought the Seed CAN-Bus Shield for my Arduino.
'My radio is already modified, so I connected to the CANH/L lines on the shield behind it and installed the example software on that device. I set the baud rate to 100kbps because I read in this forum that this is the most common baud rate for ComfortCAN in VW models.'
Now I'm getting absolutely no signal. It also displays a message saying that the CAN bus shield has been successfully initialized, but it doesn't seem to be receiving anything.
Has anyone here had any experience with this and can offer me some advice?

By the way, I found the solution. You need to disconnect the jumper P1 on the Canshield to remove the termination resistor. Then you can easily read the CAN bus data.

If anyone is interested in a similar project, I've written about everything I did on my blog.
http://tobiaswust.de/nexus-7-als-autoradio-mit-multifunktionslenkrad/

Hello, I'm new here and I hope to find the solution to my problem .

While I was browsing around here, I came across this thread.
I think it fits my problem somewhat .

I own a pre-facelift BMW E90. I was just thinking about installing a tablet, either with iOS or Android.
But I don't just want to use the tablet as a radio, like has already been mentioned in this thread; I would also like to be able to control my climate control system with it.
Does anyone have any ideas on how this could work?
I mean, input and output signals aren't the problem, right? But the temperature ranges from 16-32°C with intermediate steps, which means 32 signals .
or what?
I have to say, I'm training to be a car mechanic and I also work at BMW, but no one there could help me. And what I know about the CAN bus is quite limited. ^^

Thank you in advance .

Okay, so if the signals are coming through the CAN bus, then they definitely pose a problem. First, you need to replicate the network management system used by BMW. You could potentially bypass this by using your tablet as a gateway between the climate control system and the rest of the CAN bus.

If you not only want to read data but also manipulate signals, you may need to know the communication matrix and, depending on the situation, calculate the Cyclic Redundancy Check (CRC) for the signal groups.

Can't I use the climate control panel as a gateway?
'So that I can install it in a different location on the vehicle and have it transmit the information from the tablet to the control unit?'
Wouldn't that be more sensible, then?

Sorry for my ignorance .

To function as a gateway, the climate control unit would need to have two CAN bus connections, and you would also need to modify the software of the control unit. This is therefore not feasible.

In the first step, you should check which messages are being sent from the climate control unit.

Okay, then I guess I'll just leave it as is.

Nevertheless, thank you .