If I'm installing a carputer to work in conjunction with my stock Bose HU, how do I hook everything so that I can control the volume of both the Bose HU and carputer from the steering wheel controls? Is that even possible?

 

It is entirely possible and quite easy to implement.
you need an ipod adapter.
You need an ipod serial to usb adapter.

You need something like Girder to send and receive data in and out of the ipod adapter.

I spent couple of hundred bucks to do just this on my 06 couple.

If you need help, let me know.

 

I already have a factory Ipod adapter. But, what does that have to do with the carputer and touch screen that will have its own audio signal going to the after market amp. I want to be able to control that volume from the steering wheel as well.

 

on my 06 couple, the OEM iPod adapter goes to the trunk and so is my computer.
Rather than connecting an actual Ipod, I connect the ipod adapter to my computer
via a serial cable. So when you are pressing a button on your steering wheel, or any buttons on you Bose HU, you are sending command sequence directly into your car computer. You can capture those command and do one to one mapping to your computer to control volume or any thing you like.

I have several sequences mappped to the Bose HU to control the car computer. The FF button skips to the next track. The REW button goes back to previous track. I have button mapped to send ALT-F4 to my computer to close an active application and a few other button to turn off the monitor.

Since the OEM ipod adapter can handle aux audio input, I just route audio out from my computer to Bose HU and control its volume via the head unit.

This is a very easy and simple option to add a computer to your car and control it via the steering wheel.

 

interesting

 

For more direct carputer control from the steering wheel controls:
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