Writing messages to the CAN bus with a button press

Hello,

My name is Jan, I am 25 years old, I come from near Tübingen, and I work as an automotive electrician.

I would like to send some messages via the "User Interface-CAN" bus at 500 kbit/s from my car, using a hardware device triggered by a button press.

The context is that I want to suppress a message in the instrument cluster. There's a diagnostic service that triggers this suppression. I then measured the CAN signals and recorded the ID and data.
With this device, I can also send these messages to the bus, achieving the desired result.

"I don't want to always have to carry a laptop around; I'd like to integrate the functionality directly into a piece of hardware that displays the messages on the bus."

It would be great if someone could give me a tip on what would be suitable for this. And possibly, I might need a little help with programming .



Thank you very much, and have a nice weekend!
Jan.

"When you say 'by pressing a button', do you mean a button that is specifically installed for this purpose, or is there already a button in the vehicle that could be used, and whose status is visible on the CAN bus?"

As for hardware, I would get a cheap CAN bus simulator. So, one of the things these aftermarket radios do is extract the ignition signal from the CAN bus.
The components are proven and more cost-effective than developing your own hardware.
The circuit boards typically use PIC or AVR microcontrollers from Microchip, or ARM Cortex-M processors.
They can often be reprogrammed relatively easily.

Good evening.

I would like to install an additional button.

Okay, with which tools could one, for example, reprogram such a simulator?

Hmm, I don't know of any cheap CAN bus modules that have button inputs directly.
But you could use a button to switch the power supply of a CAN simulator on or off.

When you press the button, the circuit board receives power and sends the CAN message. This should happen in less than a second. Then you can release the key.

The question now is whether you want to buy ready-made hardware or prefer to build something yourself.

The programming depends on the microcontroller being used.

I think the easiest way to do this is with an Arduino. They are easy to program and also offer inputs.