Arduino in vehicle to control Lighting circuits.

Hey guys I am really new to arduino and I don't know where to start. Hoping to get some guidance on the project.

Let me explain what I need and want the device to do. I retrofitted a pair of headlights for my car, that have leds and color changing halos etc... Instead of having to run 3-4 switches into my vehicles cabin, I figured hey, maybe there is a way I could just control it all with an android device. What I have done is fiber glassed a smaller tablet into my dash that I use for all my gauges. I'd like to have an app that has virtual buttons that I can press to turn on a certain light.

So I am assuming I will need an arduino of some sort and a 12v relay board? Or can the arduino handle switching led halos? Another question is, If I use bluethooth will I have to connect to the bluethooth every time I start my vehicle or will it stay connected? What arduino board do you recommend? Is this something that is not worth doing?

It should be doable. I believe once a bluetooth device is paired it stays paired. You need Mosfets or transistors to drive the lights the arduino drives those devices directly ( a base resistor is needed if driving transistors).

They are only 12v leds single color, no color changing leds. The halos themselves, already have the transistors or whatever hooked up to them so just sending 12vs to them makes them work. I'm just unsure if a normal arduino can switch 12volts or if I'd have to connect the arduino to a relay board.

Yes, you need a relay board (or transistor or MOSFET, etc.). As you probably know, a relay is an electrically controlled switch.... You are replacing a switch with a switch, so t that's the "safest" solution.

But if there is no controller with unknown electronics and you just have to switch 12V power, a MOSFET is pretty "safe" too. (MOSFETs tend to make better power-switches than transistors, so let's forget about transistors.)

The Arduino chip* runs on 5V, so the digital I/O pins are +5V when high. Also, you can't put more than 5V into an input-pin.

And, the "absolute maximum" current from an I/O pin is 40mA, so you can't directly power much more than a standard LED.

I've never used bluetooth.

Is this something that is not worth doing?

:D Of course it's NOT worth doing! :D No NORMAL person is going to add LEDs and color changing halos and glass-in a custom gauge display! It' too much work and too costly, and nobody is going to pay extra for it if you sell the car. :D

....My van came with "mood lights" in the ceiling. My sister was telling someone that I had added them. I said, "No, if had put them in they'd blink to the music." So, after a couple of months of thinking about it, and a couple of months of design, programming, and re-wiring, the lights "dance to the music" with several different flashing/filckering/sequencing modes. Was it worth it??? I'm impressed! I think it's cool! But, it's behind me, so I can't see it very well when I'm driving. And, I mostly just use the van for vacations & picnics. If I show it to someone they might be amused for about 15 seconds... Nobody REALLY appreciates it but me! Nobody cares about all of the random modes & variations I programmed-in that keep me from getting bored with it. But, I'd do it again!

BTW - I used solid state relays which can be a little trickier to choose than standard relays, but they are faster and they don't "click". I could have used MOSFETs... That' just one of those choices you get to make when you design something.

  • The Arduino board has a voltage regulator so it can run off 12V. Some people worry about voltage spikes in the vehicle's electrical system, the Arduino in my van is working fine with the on-board regulator.

DVDdoug: Yes, you need a relay board (or transistor or MOSFET, etc.). As you probably know, a relay is an electrically controlled switch.... You are replacing a switch with a switch, so t that's the "safest" solution.

But if there is no controller with unknown electronics and you just have to switch 12V power, a MOSFET is pretty "safe" too. (MOSFETs tend to make better power-switches than transistors, so let's forget about transistors.)

The Arduino chip* runs on 5V, so the digital I/O pins are +5V when high. Also, you can't put more than 5V into an input-pin.

And, the "absolute maximum" current from an I/O pin is 40mA, so you can't directly power much more than a standard LED.

I've never used bluetooth. :D Of course it's NOT worth doing! :D No NORMAL person is going to add LEDs and color changing halos and glass-in a custom gauge display! It' too much work and too costly, and nobody is going to pay extra for it if you sell the car. :D

....My van came with "mood lights" in the ceiling. My sister was telling someone that I had added them. I said, "No, if had put them in they'd blink to the music." So, after a couple of months of thinking about it, and a couple of months of design, programming, and re-wiring, the lights "dance to the music" with several different flashing/filckering/sequencing modes. Was it worth it??? I'm impressed! I think it's cool! But, it's behind me, so I can't see it very well when I'm driving. And, I mostly just use the van for vacations & picnics. If I show it to someone they might be amused for about 15 seconds... Nobody REALLY appreciates it but me! Nobody cares about all of the random modes & variations I programmed-in that keep me from getting bored with it. But, I'd do it again!

BTW - I used solid state relays which can be a little trickier to choose than standard relays, but they are faster and they don't "click". I could have used MOSFETs... That' just one of those choices you get to make when you design something.

  • The Arduino board has a voltage regulator so it can run off 12V. Some people worry about voltage spikes in the vehicle's electrical system, the Arduino in my van is working fine with the on-board regulator.

Haha I guess worth it was the wrong word to use, a better one would be is it feasible. I't doesn't seem to difficult I guess really the only hard part for me is the programming.

So a few questions, I'm guessing I will need a bluethooth module? Or is there an arduino that comes with one? What arduino should I get?

Will this relay board work with the 12v leds?

http://www.robotshop.com/ca/en/relay-shield-v2-arduino.html?gclid=CLT6rZGk0MICFSxgMgodYH8A9A

Is this something that is not worth doing?

Only if you want to equip you vehicle with some "IN YOUR FACE !" electronics that prompt comments like "Wow" , or "I wish I knew how to do that !" or "Cool !"

Of course if I did something like that my friends would respond with "Right On .." :D