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LED turn signal bulb recommendation / flasher relay??

2766 Views 29 Replies 4 Participants Last post by  NewShockerGuy

I'm looking for a recommendation on LED turn signal bulbs for the CT. We have a 2016. I found another thread on a similar topic, but one thing that didn't seem clear was whether the flasher relay still exists on certain years, or if it was replaced/integrated into the instrument cluster, like on a lot of other cars.

Our car does NOT have the feature where you press the signal stalk partway to make it blink 3 times. (I personally HATE that "feature.") If you press it partway, it blinks as long as you hold it.

I purchased some 7440/7444 bulbs with built-in resistors on eBay. They mostly work, but I've found that, at least in the front, if the signal is blinking for more than about a minute (e.g. at a long traffic light), it will start to hyperflash. I'm guessing that maybe as the bulb heats up, the internal resistors don't create as much resistance, so the car thinks a bulb is burned out and hyperflashes.

One thing that's kind of weird on this car is that the rear signals use 7440, while the front use 7444. The 7444s have 2 filaments, but these bulbs do not light up when the parking lights are on; they function ONLY as turn signals. So I'm unsure why Lexus made them 7444s, vs. 7440s. I did notice that incandescent 7444 and 7440s are slightly different in that, aside from the 7444 having 4 contacts instead of 2, there is a small protrusion on a 7440 bulb that will prevent it from plugging into a 7444 socket.

So, my questions are: 1) Does the 2016 have a flasher relay that can be replaced? (If so, I know it's not easy to do based on the other post I found for 2011-2014.) Or, if not, then 2) Is there a specific LED bulb with built-in resistors that anyone can recommend?

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Yes, the 2016 has a replaceable flasher. I replaced mine. I also used VLEDs Triton V6 extreme ambers for the signals. The front bulb situation sure is bizzare with the dual filament thing, but it didn't matter with the LEDs.

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Thanks!! Is that second picture the view from looking up from under the steering column? Is that the fuse box I see? The flasher looks a lot easier to get to than described in prior years.
Yes, that is the view looking up. However, this is after I replaced the flasher and dangled it down on the wire harness. Before, it was way up there and literally impossible to see. I almost couldn't get it down (it took multiple days), and so there was no way to get it back up.
Also, is there a flasher module available that does NOT have the tap-to-blink feature?
Yes, any basic LED flasher will work for you since you don't want any of the special features. As long as it has the right connector and number of pins (there aren't that many variations)
Out of curiosity, how much slack was there on the cable that plugs into the flasher? Mine has maybe 2 inches, definitely not enough to get it down near the fuse box like yours was. I might end up having to put it back where it was, unless I can zip tie it to another cable with one hand.
Ah, in my picture, I suppose it's misleading. The flasher unit is not actually near the fuse box, but is significantly above it. You just can't really tell with the way the picture aligns, due to the nearly-impossible angle and the pitch-black darkness. So it's just zip-tied to another wire next to it with one hand.

I noticed in the picture you included above, the second number on your flasher ends in 4651. In previous posts about the flasher relay, pictures showed one ending in 4650. Do you know if there was an updated version of the factory flasher, possibly to support the tap-to-blink feature?

Does your car have navigation?
Interesting. I'm not sure why there would be different part numbers. My CT does have navigation. But I believe that all of the CTs have the tap-to-turn feature, just that the CTs without navigation require the dealership Techstream software to change it (or Carista).

The flasher module I used is actually pretty old, and was the very first of its kind. It is no longer available from where I purchased it (the guy died).

A newer version of the flasher (with another feature or two) is available here from Diode Dynamics:

The basic version of the same flasher (no extra features) is only $15:

But it ends in 4650, so I'm not sure. I never heard of anyone else having the issue you have. I wonder if the AutoZone special was just not good quality.
I did order one I found on Amazon yesterday:

It actually looks EXACTLY like the Diode Dynamics unit, and even the wording is identical. It'll be here tomorrow, but right now, the car is at a detailer getting some paint correction done, so I won't be able to try it out until at least Friday.
Ah nice, yeah they are all the same part regardless of who sells it. Hopefully this basic one works for you!
That is an interesting effect. My flasher is built to have its own tap-turn in it, but the car overrides it entirely. Though, I didn't try disabling it. I had it set to 5 blinks in my previous (faster) car, but in the slow CT, I have it set to 7 blinks.

I'm curious, why are you so strongly against the feature existing? Can't you simply not tap it?
The main reason I don't like it is that if I start to signal a lane change but then see someone coming up, I turn off the signal again. I don't want the other driver to think that I'm going to merge into them. I put on my signal before I look, and then if I see someone, if they're not going that fast but still faster than me, I quickly turn off the turn signal. That usually happens in the span of just one blink. But in my car, it'll blink 3 times (and now it will do that in the CT as well). Or, if I accidentally hit the signal stalk, I don't like it blinking multiple times and potentially confusing other drivers. Those extra blinks feel like an eternity when I want it to stop, LOL.

I also feel that 3 blinks, as is the case in most cars (the CT is the first one I've seen where you can customize the number), is dumb, because it's not nearly enough. You're supposed to signal a lane change at least a couple hundred feed before you start to move. That in itself takes at least 3 blinks. When I make a lane change, from the time I start until the time I end, it's about 10 blinks. That's why I never liked that feature.
All good points! That's why I set mine to 7 blinks, because 3 is nowhere near enough. I'm glad someone agrees. As for the other issue, yeah that is annoying, but eventually I found that it's possible to stop the blinking by committing the switch position all the way engaged, and then disengaged. I think this is just how the CT is though. On my previous car with this flasher, if I got it blinking with the tap touch, doing another tap touch would stop it. The only reason I changed the flasher was for the use of LED bulbs.
Interesting, that's definitely all new to me, so thanks for sharing your findings!
Hey Nigel, welcome over here to this forum! So to clarify, I only ever bought the one tap-turn flasher with the Strobe Pack from autowindow in 2013 before he passed away. It was $115. That was the only place to buy such a relay, it was long before offered their version for much cheaper (with a couple of extra features). DiodeDynamics now offers two LED flashers for our vehicle. The normal basic CT18 one with no extra features, and then the SmartTap one. Both should work in our car, though I haven't used their version to test. But mine does allow all of the features from both the flasher and the car to work together. The car sets the number of flashes on the tap-turn and overrides the setting on the flasher (which makes sense). So, since the car only sets the flashes in odd-number increments, 4 is not an option. I had 4 or 5 in my IS300, but then with how slow the CT is, I set mine to 7 now and that works lol.
The only thing I was not aware of with our headlights is that they are not LED/HID.. unless you got the full blown led headlights which with ALL the CT's I've looked at NONE of them had factory LED headlight as an option which is weird to me. I'm hoping I am not disappointed going back to normal halogen headlights after all these years with led/hid...etc.
a good HID or LED bulb kit works well in the projector low beams. I did Morimotos in mine until I did a full projector swap/retrofit instead.
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