Read CAN data and output values as control signals

Hi everyone,

I'm new here, and this whole topic is quite new to me. I'm facing a problem and I'm looking for a way to convert CAN bus values into 12V control signals. I essentially need a programmable/configurable CAN bus interface.

Background: We are converting US-made vehicles to meet EU standards. In some cases, these vehicles transmit additional data via the brake/turn signal lights, or modulate the signals in a way that prevents the use of standard control systems for separating brake and turn signal functions.

I am therefore looking for a way to read information directly from the bus, instead of relying on a brake/turn signal separation, and to send corresponding signals to the turn signals via relays. Online, I've found some pre-built interfaces that, for example, output a control signal when the ignition is active, at different light settings, or even when the turn signals are on. This could be used for video surveillance tools, for instance: turning on the left turn signal could trigger a control signal to activate the left camera.

However, what I'm missing is: hazard warning lights.
I absolutely need to redirect the hazard light signal to both turn signals (using a relay).

We are looking for an interface that reads 3 CAN values and provides 3 control signals accordingly.
- Left turn signal active.
- Right turn signal active.
- Hazard lights activated.

I haven't found anything that's ready. Are there any interfaces that are so individually programmable?
If so, which ones - and which ones would you recommend for implementing something like that?
...or perhaps there's someone out there who has experience with this, wants to earn a few extra euros, and could build it for me?

Best regards from Salzburg, and many thanks.
David.

Hi David,

You need to know which messages are being transmitted on which CAN bus in your vehicle. That also varies depending on the vehicle.

Best regards, Rainer.

Hello Rainer,
Thank you for your quick response!
It's a Ford Lightning F150.
So, the new electric version of the F-150.
Does that help?
Best regards,
David.

eldu wrote:

Hello Rainer. Thank you for your quick response! It's a Ford Lightning F150. So, the new electric version of the F-150. Does that help? Best regards, David

Not to me, but to you.

You need to determine which CAN bus contains the signals you require. I suspect it's the CAN bus for comfort functions. For example, it can also be connected to a radio.
Okay, so I need to obtain circuit diagrams, tap into the CAN bus, and listen to what data is being transmitted and when.
KCANMonitor has a feature that highlights only the time differences in messages, which makes it quick to identify relevant functions.

Best regards, Rainer.

I would connect the "high" and "low" signals directly to the control unit where the turn signals are also connected.
Using the logger you linked and a PC, I can probably figure out how the turn signal signals are being sent, right?
And what hardware converts the signals into control signals when they are active? So, what else do I need?
It would need to be a component that can accomplish this without requiring significant processing power, startup time, delay, or power consumption. Something based on microcontrollers, or how should I imagine that?
Thank you again, and I'm sorry that I'm missing all this basic knowledge. I'm starting from 0, but I'm ready to learn quickly .

Hello.

Quote:

With the logger you linked and a PC, I assume I can figure out how the turn signal signals are being sent - is that correct?

Quote:

And which hardware converts the signals into control signals when active? So, what else do I need? It would need to be a component that can accomplish this without requiring significant processing power, startup time, delay, or power consumption. Something based on microcontrollers, or how should I imagine that?

Yes, some kind of microcontroller that listens to the CAN bus, analyzes the signals, and generates the switching signal you want based on that analysis.

I would be interested to know which provider you choose and what reasons you have for that decision.

Best regards, Rainer.