Need help: Using DRL to switch Angel eyes and HighBeam

[bluebastide]

Hi, I am new to this forum and need some help. I have this small project to do and would like to do it as clean as possible but as simple as possible as well. I can help myself for soldering parts and building a small project but that's all. Your ideas including parts and wiring schemas would be greatly appreciated.

The project: DRL stands for Day running light, where in some countries cars must come with this feature which basically make sure there is always some headlight on after a car is started. On my son's BMW 328i 1997, DRL sends around 6-8v to the highbeam bulb when the car is started and more when he turns on the high beam. The idea is to filter this voltage variation to manage two circuits: the angel eyes (with full 12VDC) and the high beam (full 12vdc obviously). See the diagram attached.

A key element: when the highbeam are turned on, the angel eyes must be kept ON as well.

I miss two information at this point: I will check when my son is back.

- Would the High beams work if the car is only on Accessories ! thus I suppose the DRL Feed would provide automatically 12VDC but then this filter would also turn on the angel eyes which is not a problem
- The actual voltage range of the DRL and HighBeam inputs.

Thanks in advance for your ideas.

 

[part_time]

Use a relay to power the angel eyes. And use drl + to switch the relay. You can get the relay and the local auto parts store.

 

[bluebastide]

Use a relay to power the angel eyes. And use drl + to switch the relay. You can get the relay and the local auto parts store.

Hi, the relay would only turn on the angel eyes but not manage the high beam unfortunately. Thx anyway

 

[part_time]

What do you mean manage the high beams? You want the eyes to come on with drl and high beams correct? Or Just the drl's? Or do you want high beam and eye on(full12v) all the time

 

[bluebastide]

What do you mean manage the high beams? You want the eyes to come on with drl and high beams correct? Or Just the drl's? Or do you want high beam and eye on(full12v) all the time

Neither: I'd like to angel eyes ONLY on when voltage is 5 or 12v and have the high beam on ONLY when 12 volts is supplied. The relay would turn on the angel eyes all the time indeed but would also send 5v to the high beam bulb acting as a DRL. I want to filter OUT low voltage (say below 7v).

I should have added this in my intro. thx.