Bimmerfest - BMW Forums

Bimmerfest - BMW Forums (http://www.bimmerfest.com/forums/index.php)
-   E90/E91/E92/E93 (2006 - 2013) (http://www.bimmerfest.com/forums/forumdisplay.php?f=99)
-   -   Changing fog lights to LED DRLs (http://www.bimmerfest.com/forums/showthread.php?t=672597)

MilosFreeM3 01-26-2013 09:36 PM

Changing fog lights to LED DRLs
 
Changing fog lights to LED DRLs:

Looking for help from my fellow-BMW enthusiasts.

Loyal for 17 years to BMWs I went to the dark side as I could not resist a great
deal I found on my current 2009 SL550. No worries - my E46 is still in our garage
and coincidentally just tonight we broke 100,000 miles after 9+ years together.
BTW, my wife is thrilled that she ‘inherited’ the car from me 2 months ago ;- )

I liked everything about my car and was not thinking about doing any mods until
I saw a picture where someone successfully converted fog halogen lights to more
modern LED DRLs. My installation went without a hitch and I was very happy
with the overall look and execution. But we are not ‘home free’ just yet.

Since the wattage is lower on LEDs – as we expected, the lights are causing errors
on the dash board. Worse yet, they are not operational yet and are only giving
out some blinks and flashes every so often. My installers expected this and had
a few resistors ready to ‘fool the computer’ that the current is as it should be.
They tried 4 different values, but this only accomplished flickering and different
intervals. No steady-on light and of course – the errors are still on my dash.

I know that MB SLs are not cars that are modified extensively, so I am turning for
help from any car enthusiast that can shed some advice or suggest that I contact
someone (shop / company with accessories?) with knowledge and necessary parts.

Thanks in advance for any input...
(sorry this is not directly BMW related, but I was hoping that the same folks that
know how to overcome these challenges, would know it regardless the make & model)

http://i229.photobucket.com/albums/e...conversion.jpg

HPIA4v2 01-27-2013 03:22 PM

You'll need to put the resistor in parallel, across the light bulb terminal. I'll say 1W 240-ohm resistor will do. It really to fool the LCM to think there is incandescent bulb across the terminal.
If this still fail, I'll put the original bulb in place to reset the computer then switch it back to LED. Unless you have a good reset tool like GT or auto-logic to reset lightbulb burn message.
GL.

MilosFreeM3 01-28-2013 08:14 PM

Quote:

Originally Posted by HPIA4v2 (Post 7341877)
You'll need to put the resistor in parallel, across the light bulb terminal. I'll say 1W 240-ohm resistor will do. It really to fool the LCM to think there is incandescent bulb across the terminal.
If this still fail, I'll put the original bulb in place to reset the computer then switch it back to LED. Unless you have a good reset tool like GT or auto-logic to reset lightbulb burn message.
GL.

Thank you for your reply.
Just curious - how did you come up with 1W 240 Ohms.
The OEM fog lights are 55W. I am just curious if the math makes sense for 1W/240 Ohms in place of 55W bulb.
NOT doubting you - just curious about the formula. I used to be able to calculate this - but this was many, many years ago ;)

HPIA4v2 01-29-2013 07:09 AM

Quote:

Originally Posted by MilosFreeM3 (Post 7344929)
Thank you for your reply.
Just curious - how did you come up with 1W 240 Ohms.
The OEM fog lights are 55W. I am just curious if the math makes sense for 1W/240 Ohms in place of 55W bulb.
NOT doubting you - just curious about the formula. I used to be able to calculate this - but this was many, many years ago ;)

I am guessing most of it, but the idea is to at least provide at least 20mA draw current (12V/240ohm ~ 20mA) for LCM (light control module) to sense there is resistance there, fooling it to think there is good light bulb there. But also dissipate very small amount of heat about 20mA x 240-ohm ~0.5Watt when your LED is on, don't want to design a space heater inside your headlamp nor loading up the LCM either.

MilosFreeM3 01-29-2013 07:28 AM

Thanks for the explanation. Much appreciated.
M.

MilosFreeM3 01-31-2013 07:23 AM

All good now. Someone recommended a really good car stereo shop.
I took the car there and they had everything figured out in one hour.
They were able to calculate the correct load resistor and now there are
no error messages on my dash board. The LEDs are hooked up to the
original fog light circuit so I control them with my fog light switch.

Thank you for your replies !!

http://img.tapatalk.com/d/13/01/31/e7e7e4a3.jpg

http://i229.photobucket.com/albums/e...0/uveru6e5.jpg

heztheone 01-31-2013 09:46 PM

looks great :thumbup:

E92-Lighting 02-01-2013 12:52 PM

looks great, we have CREE fog lights as well now


All times are GMT -7. The time now is 02:15 PM.

Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
© 2001-2011 performanceIX, Inc. All Rights Reserved .: guidelines .:. privacy .:. terms