Background

Some time ago I put a JVC KD-X342BT into Renault Clio II, originally equipped with Update List radio device. This car is equipped with a stalk remote control, placed next to ignition switch. Also, mentioned JVC radio has a single, blue-yellow cable at its back, labeled as "steering wheel remote". Since installation I wanted to connect it all together and use the stalk remote. So I started looking for a solution, and I've found several similar projects. All links I used can be found in Credits section.

Assupmtions

  1. Use existing connectors as much as possible.
    It wouldn't be acceptable to disassemble half of the car just to plug some wires. Existing connectors allowed original radio to communicate with remote, so there must be some kind of connection. This communication takes place over CAN bus.
  2. Automatically increase and decrease volume basing on current car speed.
    I drive on highways quite often. Unfortunately, noise level increases greatly when I reach speeds above 100 km/h. In such cases I need to turn volume up and then turn it down as I decelerate. It is a bit burdensome to do it manually, and original radio had this feature built-in. It would be great to have this function.
  3. Utilize central display in some way.
    Original radio uses central display to show RDS info, FM frequency etc. Aftermarket radio of course isn't connected to it, so display shows only time and external temperature. I thought I could utilize it to display car's speed. 

Hardware

  • Stalk remote control (part no. 820058695),
  • AFFA2 display (part no. 8200380298 - probably, looks like mine),
  • JVC KD-X342BT (presumably will work will all other JVC radios which use single wire interface for remote control).

For wiring diagram look here.

Software

Source code is available on my Github.

Credits

Big thanks to my brother who designed and 3d printed the enclosure!

List of links I used in any way in order to build this thing:

... and countless C++ and Arduino reference pages I had to read!