BMW E36 Blog

Turning Your BMW Lights On Automatically At Night . . . Soldering

18th March 2008

Turning Your BMW Lights On Automatically At Night . . . Soldering


Before I start this post. There’s one thing that is really confusing me? Why I’m not getting any response for these articles from you guys? Don’t you like to make your car headlights turn on automatically like the 200X cars? Isn’t that cool? Come on people, let me hear what you think good or bad 😈 .

I wrote four articles until now about how you can make your BMW lights turn on automatically at night. In the first post, I proved that this should be something easy to implement inside a BMW E36 car. In the second post, I presented a circuit diagram that will help you create the electronic circuit that is supposed to control your lights and turn them on automatically when it gets dark. In the third post, I wrote about my first attempt to implement this circuit and told you that it’s partially working but it needed some enhancements. In the fourth post, I created a video with the circuit implemented on breadboard and connected directly to my brother’s car lights. The video showed how the car lights turned on when I covered the light sensor with my hand (tricking the sensor to "think" it’s dark). So, the circuit is working correctly as intended.

In this new post, I soldered the circuit on permanent board and the end result looks like this:

I made sure that this circuit has the following:

1. Two wires for power (positive and negative).
2. Two long wires that are connected to the external light sensor. I made them long because I’m still not sure where I’m going to place that sensor. Take a look at this:

3. Three wires connected to an external variable resistor, this will allow us to adjust how sensitive the unit will be for light. Take a look at this:

4. Three wires that will deliver current from the battery directly to the headlights when it becomes dark.

With this circuit implemented, I think I’m ready to integrate this into my car. I hope in the next week, I will post a video here while I’m driving my car under a tunnel and show you how everything will work. :-). But please let me know what do you think of all this? Also, if you have any ideas about where I should put the light sensor, please let me know.

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posted in Do It Yourself, Electrical, Technical Info, Tips & Tricks, Uncategorized | 2 Comments