Third Brake Light, LED's, and Cruise Control works!!!
 

Been wanting to replace the 921 Halogen bulbs in the 3rd brake light with LED bulbs, without loosing cruise control ability since I got my 2010 LT back in 2015. For ME, the "why" is better daytime visibility when braking since at least 80% of my driving is daytime. True, the halogen's are decently bright to start with, but if the sun is in the wrong place behind you while driving, it can be hard to see that third light come on. Some extra brightness from LED's can help overcome that.

I tried this when I first got the 2010 LT, lost cruise control with LED's, went back to halogens. Fast forward to 2026 & a new to me 2010 LS.... I figure, there's more options now ,& probably some that work....

LED's that WORK will be in the GREEN section, those that don't work will be in the RED section.

+++++++++++++++ CRUISE CONTROL WORKS WITH THESE ++++++++++++++++++

>>>>> This is IT for me!!! http://www.amazon.com/dp/B081YHRNY8?...n_title_1&th=1 LasFit 921 LED RED Model # T-T15R <<<<< noticeably brighter than the L-T15R bulb, this is about what I wanted to begin with, and cruise control works with them!!!

http://www.amazon.com/dp/B0F6S2HKLR?...sin_title&th=1 LasFit 921 LED 6000K(blue-tinted white) - brighter than new Sylvania 921LL halogen, but not as bright as I would prefer. They do work, but give a slightly orange appearance (that I don't like) to the brake light when the brakes are applied vs Halogen bulbs.
http://www.amazon.com/dp/B081YJWBR9?...sin_title&th=1 LasFit 921 LED RED Model # L-T15R - same brightness as the 6000K version but doesn't give that orange appearance to the brake light. These are the one's I'll be using - but will still be searching for a brighter bulb!
ADDED 3-12-2026:
http://www.amazon.com/dp/B08CXBFWWW?...sin_title&th=1 PhinLion 921 LED RED - described as "super bright", and with 24 LED's onboard, I had hoped they would live up to that, identical in brightness to the LasFit, but only $5 per bulb (making them the same price as Sylvania 921 Long Life halogen bulbs) are a better deal.
http://www.amazon.com/dp/B09YPVF4T2?...sin_title&th=1 KISLED 921 6000K - also described as "super bright", but are actually dimmer than the halogen bulbs.


LasFit 194 marker light LED's also appear to work, but are about the same brightness as halogen 921's, so I did not try a full set. I say "appear" because I had 2 of them and two of the SeaLight 921 LED's in the 3rd brake light at the time.

<<<<<<<<<<<<<< These do NOT work to maintain cruise control >>>>>>>>>>>>>>>
http://www.amazon.com/dp/B0F8VDD1HP?...sin_title&th=1 SeaLight 921 LED's- I really wanted these to work, they are the brightest LED's I've found so far and are clearly visible even with the sun behind the HHR. However, they do make for terrific reverse/backup lights!!!
http://www.amazon.com/dp/B0728DYR9H?...sin_title&th=1 Auxito 921 LED's in either RED or 6000K-similar to the SeaLight but with passive cooling fins and not quite as bright.
http://www.amazon.com/dp/B0186P1MUW?...fed_asin_title SIR IUS LED 194 LED's- cheap, but definitely not bright - these do however make great LED's for your tag lights & marker lights!


All the 6000K bulbs that I'm not using in the car will be used to make battery powered emergency lighting for hour+ power outages - i.e. from severe thunderstorms, vehicles hitting power poles, hurricanes, etc.... I have a nice 300AH 12V lithium battery for the task! Should provide about 5-7 days worth of lighting for the whole house from a single charge, & it can be recharged overnight from a generator!

So I found one that works, and is even brighter, It's another LasFit, but slightly different style of bulb. Most importantly, it works with the Cruise Control, and is almost as bright as the SeaLight LED's!!!


I think because of it being filmed at night, the differences in brightness don't show up as clearly on camera, so I might try it again during the day to see if brightness difference is more apparent. Though I might have to get my Olympus dslr out & shoot manual setting to show the differences.

From the Left: Left bulb is LasFit 921 LED model # L-T15R > 2nd bulb is Sylvania 921 Long Life Halogen (New) > 3rd and 4th bulbs are LasFit 921 LED Model # T-T15R. Visually, to my eyes, the L-T15R appears about 15% brighter than the 921LL, while the T-T15R appears about 30% brighter than the 921LL.

And if any one is curious as to how my interior is so bright, those are LasFit Model No:L-42MM 42mm festoon LED's lighting it up!

The LL bulbs are inherently not as bright. That is how they get a couple more hours life.

and thus the problem.... any LED's should be at least as bright as an LL bulb, but some are not, which screams the question, what are they supposed to be 300% brighter than :confused: and is also why I had to try out so many bulbs :dizzy: Got 4 sets I'll be returning today!