[epiclarisse]

I also faced the problem that many LED bulbs from specialty stores don't fit the Focus RS carvings. Unfortunately, you will not be able to predict this even if the instructions indicate it's suitable. But the manufacturer must have a list of confirmed fog lamps. I bought the first good smart led light I saw on Amazon. And I'm lucky it fits the Focus RS. Try to buy this. It will be less than $50 since you can even order them in bulk. Although, if you don't need so many of these bulbs, you can only order two or four for the future. I'm ready to vouch that they are suitable for carving fog lamps.

 

[BamaBob]

Just a bump, they are currently for $16.79 at amazon:

https://www.amazon.com/gp/product/B0875FSBD5/ref=ppx_yo_dt_b_asin_title_o00_s00?ie=UTF8&psc=1

Is anyone else using the SEALIGHT fog light LEDs from Amazon? I bought a set in May 2019 and everything was fine, fit, color, brightness all were good. It took nearly 3 years before I realized that these LEDs were causing another issue that was so strange that I almost never made the connection. The short of it is they create interference with the FM radio. I had noticed for years that at seemingly random times, my FM radio reception would go to crap, especially any stations that were HD. Since at other times the reception was fine, I thought I had a loose antennae connection. Not sure why it took me so long to notice the seemingly random times it would not pick up any stations was at night. Once I realized that, it didn't take me long to isolate the fog lights as the problem. I found this thread as now I am looking for some replacement LEDs, the dual color ones have piqued my interest, may have to give those a try. I've been wondering lately if the yellow would actually aid in visibility when it actually is foggy like this morning.

 

[FuKuRoKu]

Is anyone else using the SEALIGHT fog light LEDs from Amazon? I bought a set in May 2019 and everything was fine, fit, color, brightness all were good. It took nearly 3 years before I realized that these LEDs were causing another issue that was so strange that I almost never made the connection. The short of it is they create interference with the FM radio. I had noticed for years that at seemingly random times, my FM radio reception would go to crap, especially any stations that were HD. Since at other times the reception was fine, I thought I had a loose antennae connection. Not sure why it took me so long to notice the seemingly random times it would not pick up any stations was at night. Once I realized that, it didn't take me long to isolate the fog lights as the problem. I found this thread as now I am looking for some replacement LEDs, the dual color ones have piqued my interest, may have to give those a try. I've been wondering lately if the yellow would actually aid in visibility when it actually is foggy like this morning.

Your issue is referred to as electromagnetic interference (EMI), it's common in cheap Chinese electronics because they don't want to spend the extra money for shielding or higher quality components. For foglight bulbs, I highly recommend Diode Dynamics SLF (for foglights) or SL1 if you need even brighter (but the SL1 is designed for headlights). Diode Dynamics bulbs are designed, engineered, and manufactured in the USA (St. Louis) with a 3 year warranty, I've toured their facility when they had a car show. They do extensive hot/freeze, salt water, vibration, reliability, and thermal testing on all their products. Their lumens values may seem lower than other brands advertise but Diode Dynamics uses true lumen values tested with $10k integrating sphere whereas most other companies just use fake theoretical values. Their bulbs are also made to emulate the stock beam pattern as closely as possible so that the light is correctly focused and glare is minimized.

Here's their SLF 3000k Yellow in my RS next to the stock halogen bulb, the LED is a lot brighter. Note the mounting tab is broken on my right side fog housing so that's why the right side is aimed higher.

 

[nicklulu]

Your issue is referred to as electromagnetic interference (EMI), it's common in cheap Chinese electronics because they don't want to spend the extra money for shielding or higher quality components. For foglight bulbs, I highly recommend Diode Dynamics SLF (for foglights) or SL1 if you need even brighter (but the SL1 is designed for headlights). Diode Dynamics bulbs are designed, engineered, and manufactured in the USA (St. Louis) with a 3 year warranty, I've toured their facility when they had a car show. They do extensive hot/freeze, salt water, vibration, reliability, and thermal testing on all their products. Their lumens values may seem lower than other brands advertise but Diode Dynamics uses true lumen values tested with $10k integrating sphere whereas most other companies just use fake theoretical values. Their bulbs are also made to emulate the stock beam pattern as closely as possible so that the light is correctly focused and glare is minimized.

Here's their SLF 3000k Yellow in my RS next to the stock halogen bulb, the LED is a lot brighter. Note the mounting tab is broken on my right side fog housing so that's why the right side is aimed higher.

View attachment 364680

I've been driving at night and early in the Mo' (also have my auto light on) have not gotten with the HD radio reception with deez LEd Fog lights.

 

[nicklulu]

I also faced the problem that many LED bulbs from specialty stores don't fit the Focus RS carvings. Unfortunately, you will not be able to predict this even if the instructions indicate it's suitable. But the manufacturer must have a list of confirmed fog lamps. I bought the first good smart led light I saw on Amazon. And I'm lucky it fits the Focus RS. Try to buy this. It will be less than $50 since you can even order them in bulk. Although, if you don't need so many of these bulbs, you can only order two or four for the future. I'm ready to vouch that they are suitable for carving fog lamps.

I clicked on your link:

............................................ and you are now banned.

 

[TonyC]

I bought a set of Sylvania led fogs when it went on sale +$15 gift card. So $50 and three year warranty View attachment 348454 Plug and play, no additional tail to tuck in.

These do not fit in the housing on my 17. Buyer beware.

 

[NISMO_IX]

These do not fit in the housing on my 17. Buyer beware.

I would assume the housing was the same all three years, interesting.

1st post, welcome!

Correction: it looks like @nicklulu had brought attention to fitment later in the thread.

 

[lemontlucas]

These bulbs did not fit inside my housing. They are too big for my 2017 RS

 

[Yukon Corleone]

These bulbs did not fit inside my housing. They are too big for my 2017 RS

I think somewhere in this thread that you have to make the hole bigger.

 

[bentontynch17]

I know I’m late to the thread but I just tried installing these exact bulbs in mine and the will not clear the metal shield inside the housing. How did you make them fit