Reading Car Indicators Signal with Arduino

Other Hardware General Electronics
1

Hi everyone.

What's the best way of reading car indicator signals with an Arduino preferably via the digital pins?

This is then used to show some sign on an LCD.

Any help would be appreciated.

Thanks.

2

The wires going to your turn signal bulbs will have a voltage that goes between (about) 0V and (about) 12V. A [u]Voltage Divider[/u] can be used to bring the voltage down to 0-5V for the Arduino.

The total resistance in your voltage divider can be around 10K (it's not that critical). The resistances don't have to be exact but the resistor ratio should be close to what you calculate. So, choose readily available values that are close to what you calculate. Then, since the "12V" is not perfectly regulated and can be a bit higher, it's a good idea to put a "protection diode" between the Arduino's input and it's 5V supply.

The LCD wiring/programming is quite a bit more complicated, so I suggest you study some examples.

3

Thanks for the reply. Much appreciated.

I now how to program LCDs etc, no worries there. Is voltage dividers the only way?

Thanks.

4

Is voltage dividers the only way?

Of course not. You could put a phototransistor that reacted to the actual light from the turn signal, you could clamp on an inductive meter of some sort in some fashion on some cable and read flow, you could use lever switches to determine when the driver physically turns on the indicators, etc.

With a little more feel for what you are doing and what you want to accomplish, I'm sure DVDDoug or somebody could provide more help.

5

Using a colour LCD to build a selection of warning light to be shown on it. I'd like to get the signals from the lights on the dashboard. I also wanna show the indicators on this.

Hope this helps.

6

Anybody?