X164 GL550 LED Fog Light canbus error, need resistors?
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Newbie
Joined: Sep 2017
Posts: 10
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From: Atlanta area, USA
2009 GL550 X164, 2009 SL550 R230
X164 GL550 LED Fog Light canbus error, need resistors?
Guys, I have a 2009 GL550 and have replaced the fog light bulbs with LED's and they work fine but I have an error message on the dash that says check bulb. I assume I need a resistor and see all kind of answers on this. Anyone know if this one below will work? It is a 50w 6ohm resistor and has the same plug as the H11 Led's I installed.
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Joined: Jun 2010
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From: Emmett, ID, USA
2007 GL450
Guys, I have a 2009 GL550 and have replaced the fog light bulbs with LED's and they work fine but I have an error message on the dash that says check bulb. I assume I need a resistor and see all kind of answers on this. Anyone know if this one below will work? It is a 50w 6ohm resistor and has the same plug as the H11 Led's I installed.
https://www.amazon.com/NEX-Resistor-...054169039&th=1
https://www.amazon.com/NEX-Resistor-...054169039&th=1
Power = voltage squared divided by resistance
6 ohm on 14V will dissipate 196/6 watts = 33W
This should be more than sufficient. Your LED bulbs probably dissipate around 30W, and 30 + 33 = 63W. The CAN bus has a tolerance for low current; it does not demand that the bulb be full power. I found that small (1W) LED bulbs for the marker lights work fine with a 100 Ohm resistor; this is just adding about 1.5W to make about half the current the bus is looking for. So you could probably get away with a higher resistance resistor than 6 ohm, but it will be a matter of trial and error to figure out what works. I happened on the 100 ohm resistor when I accidentally ordered it instead of lower resistance.
The resistor you are looking at is running at over 50% of rating, which is a bit uncomfortable. Make sure you put it in a well ventilated location. But the fog lights will probably be used in cool conditions, so that would help.
I'd be more inclined to try a 10 to 20 ohm resistor.
