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Car Driving lights - Quick Help Pleeeeease

SN1TZR

Dec 13, 2012
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Joined
Dec 13, 2012
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Hi Guys

Im new to this forum but i was just hoping someone could help me with some LED driving lights im putting on my BMW.

Two driving lights on the front of the car. They come with a loom that connects to -ve, the car accessory power supply and also the headlights so they are on whenever the key is turned and turn off when i turned on the headlights.

However, i would like to also allow them to turn on with the interior lights so that when the car is unlocked by remote (and the interior lights come on) the LEDs also come on. I can run a wire through from the interior lights but what do i need in terms of transistors, relays etc to join this on to the loom accessory power connection. Or is it as easy as joining a relayed interior light signal to the accessory power lead?

Thanks heaps in advanced your help is much appreciated.

Rowan
 

KrisBlueNZ

Sadly passed away in 2015
Nov 28, 2011
8,393
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Nov 28, 2011
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Hi, and welcome to the forums :)

This depends on how the interior light, and the headlights, are controlled.

In a traditional setup, the headlights and the interior light are both activated by a positive voltage from the electrical system. This voltage is switched either by switches (i.e. the headlight switch, and switches in the doors), or by relays that are controlled by those switches.

Obviously this is a pretty smart car, if it has remote unlock which also turns on the interior lights before you open the door, right? It may use a quite different method of switching the lights, which may make it very difficult to do what you want with a simple relay and a "diode-OR" (look it up).

Finding out how the lights are controlled may turn out to be difficult, even if you DO have a wiring diagram... which I'm assuming you don't.

There are also safety issues involved when you modify a car's wiring, and it is not a good idea to do it yourself if you're not experienced.

The only thing I can safely suggest is that you take it to an authorised BMW service company and ask them to install the driving lights with that feature.
 
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