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LED turn signal bulb recommendation / flasher relay??

2767 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.
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.
Also, is there a flasher module available that does NOT have the tap-to-blink feature? I honestly hate that feature, and the car has the ability to do that already, but I turned it off. (Wish I could turn it off on my Honda Accord! The CT is my wife's car.)
It took a bit of work, but I got the flasher relay out! Now I just have to get a new one... LOL. It's hanging right now, but that's OK, because the car is going in for paint correction work that will take a few days, so it won't get driven much.

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.
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)
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?

I picked up a flasher module at AutoZone today on my way to work. It was about $20, and looked like the right one. When I installed it, the turn signals worked, but the hazards wouldn't go on. I put the original back in, and then the hazards worked again. So the one I got was obviously not the right one. It was a Novita LM449:

I went by an O'Reilly, and they quoted me $47.99 for an STI EFL47 flasher, which they did not have in stock. Seems kind of expensive. I already ordered a flasher on Amazon, but it also had the part number ending in 4650, so it may not work for me. I may try one of the ones you got as well, since it worked for you. But that's why I was wondering if you have navigation -- maybe it's a different flasher because of the tap-to-blink feature; that feature may only be available on models with navigation.

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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.
That's entirely possible. Or I may have gotten a defective one. But it was the only one they had, so I couldn't exchange it. 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.
Got the car back from the detailer today, so I was able to try the flasher I got on Amazon. It works! Turn signals and hazards both work normally. So I guess the one I got at AutoZone was either bad, or not the proper type for this car.

There was, however, one interesting side-effect: Perhaps the flasher is designed to do the 3-blink tap-to-flash thing, because even with that feature disabled in the car's menus, it will still tap-to-flash 3 times. If I change the setting in the car to 3, it still blinks 3 times. If I change it to 5, 7, 9, or 11, it blinks 5, 7, 9, or 11 times. But at either 3 or Off, it blinks 3 times. Minor annoyance, but not really a problem, since I'm used to that in my own car (2022 Honda Accord -- the CT is my wife's).
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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.
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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.
I tried that, but it didn't work for me. I did a bit of experimenting with the different settings, and here's what I found:

  • Regardless of the car's tap-to-blink setting, if I turned the signal all the way on and then off again immediately, it blinked 3 times. No matter what. Didn't matter if the car's setting was Off or 11 blinks, I'd get 3 blinks. So that, I'm guessing, is a function of the flasher module.
  • If I only tap the signal stalk and release it, i.e. not engage it all the way, then it would blink the number of times configured in the car's settings. The only exception there is that if the setting in the car was Off, it would still blink 3 times.

So, I'm guessing that the flasher must have some kind of built-in logic that, no matter what you do, makes it blink a minimum of 3 times. If the car tells it to blink once, it blinks 3 times. If the car tells it to blink twice, it blinks 3 times. If the car tells it to blink 3 times, it blinks 3 times. If the car tells it to blink MORE than 3 times, then it blinks whatever it's told.
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Hi Nigel, welcome to the forums! :)

I'm about to get a 2016, and I see you said your's is 2016. So no issues with the built in systems that you can program via tech stream to change the turn signal flash and the LED relay replacement?
When you say Tech Stream, what are you referring to? Does your vehicle have Navigation? Mine does (well, it's my wife's, not mine, but I'm calling it mine for purposes here). With Navigation, you can program the number of flashes through the menus. Without navigation, you either need some kind of software and a device to connect to the OBD port (is that Tech Stream?), or the dealer has to do it. I don't know if it's programmable through the audio system or the "DISP" button on the steering wheel if you don't have navigation.

I ended up buying this flasher module on Amazon, made by iJDMTOY:

I had tried what seemed like a similar one from AutoZone, but when I put the AutoZone one in, my hazards wouldn't work. Indivdual turn signals were fine, but no go on the 4-ways. But this one from Amazon works fine.

As far as bulbs go, I went with bulbs from my trusty supplier, SuperBrightLEDs. I kept trying different bulbs from Amazon and eBay with built-in resistors, but they were never consistent. It seemed like they would heat up and then cause less resistance. If I was sitting at a long traffic light with the blinker on for more than about a minute, it would start hyperflashing. I was pretty much ready to give up on it until I discovered some threads here that led me to learn that the flasher in the CT is replaceable. Since a lot of newer cars don't have replaceable flashers, I assumed the CT was among them until I found the threads here. So I was able to return the bulbs with built-in resistors, and get the proper bulbs from without resistors, and they work beautifully.

Is the basic diode dynamic's the same version that you have from the person that used to make them or does yours also have other features?
As TobiasSing mentioned, Diode Dynamics makes 2 flashers for the CT. I haven't tried either of them either, since the one I bought on Amazon works fine. There is one small quirk, which I will describe below.

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.
Here's the experience I had with the flasher from Amazon, and the quirk I mentioned: I have the tap-to-blink feature turned OFF in the car. With the old (factory) flasher, Off was Off. With the new flasher, though, even with the setting Off, it still blinks 3 times if I tap. If I set it to any of the numbers other than Off, it will blink the correct number of times. So for me, Off = 3 blinks, 3 = 3 blinks, 5 = 5 blinks, 7 = 7 blinks, 9 = 9 blinks, and 11 = 11 blinks.
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TechStream is the diagnostic software that Toyota/Lexus uses. It can trouble shoot and make changes with the car and all of it's modules..etc. IE: I can program the car so that holding the unlock button on the fob rolls all the windows down, or I can change certain customization settings that you'd normally have to go to the dealer to. I work on all of our cars so I have all the software to be able to trouble shoot and do what the tech at the dealer would do.
Wow, that must be a nice thing to have! :) I had to have the dealer program the window thing, and I also had them turn off the reverse beeper. Well, not turn it completely off, since you can't do that, but I had them change the setting so that it only beeps once instead of continuously. That continuous beeping was really annoying! I mean, hybrid or not, why do I need my car to beep at me when it's in reverse? I think I'd know if it was in reverse, especially wtih the backup camera screen looking right at me. Anyway, that may be something you wish to turn off as well.

I'm going to take the diode dynamics smart tap relay that I have on our Solara and try it on the CT when I get it.
Is it the same relay?

I figured something might conflict since the tap to flash is 3 by default and then you have the on board system trying to do it's thing. That's probably why when you have it set to zero at the car level since the minimum flash cycle of the relay is 3 it will always do 3...
Since I didn't buy the Diode Dynamics relay and just bought a more generic one from Amazon, I was assuming that it did not have the tap-to-blink logic built-in, since it was cheap. There was no mention of tap-to-blink in the Amazon description. But who knows, maybe it does have that logic.

But a cool feature of the tap flash relay from diode is that when you lock or unlock the car the parking lights stay on for about 30 seconds which is a great indication when you lock/unlock the car plus it's a little bit of a security feature being so well illuminated. I'm not sure if the CT has that feature by default. I know my RCF and my wife's NX does have the delayed headlight/light feature.
That is a nice feature! The CT does not have that by default. The inside lights will stay on for about 30 seconds or so when you unlock, but not the outside lights.

I did, however, recently discover something else kind of cool: Even without unlocking with the fob or touching the handle, as you get up next to the car, if it senses the key fob, it will turn on the inside lights. Kinda neat that it will do that without you having to even unlock it!

My CT that's coming does have navi, all the ones I were looking at were specifically not, but then when I realized the back up camera is in the rear view mirror and tiny, I did not want that at all.
Yeah, we were looking for one with navigation specifically because of the backup camera being on the screen and not in the mirror. Seems that the CT has 3 options as far as the backup camera goes: 1) None at all; 2) In the rear view mirror for non-navi models; or 3) In the screen for navi models.

I like this design a lot because it's not huge and it fits in a very compact area yet it's extremely bright and it has 360 degree coverage along with forward facing leds.
The forward-facing LEDs are nice for the front, although I have found them to be actually TOO bright in the rear. I have some bulbs with built-in resistors in my 2022 Honda Accord hybrid, since the Accord doesn't have a replaceable flasher module. There have been a couple of instances where my wife and I were in each other's cars, and I noticed that at night, the turn signal bulbs were VERY bright -- almost blindingly so. So now I feel bad for people behind me! The bulbs I got from SBL for the CT are also pretty bright, but not as bright, and also, the bulbs go in on kind of an angle in the CT, so the LED SMDs on the end of the bulb are actually facing diagonally up, not straight out, so they aren't blinding.

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.
Yeah, I was kind of disappointed about that, too. I believe LED headlights is an option on the CT, at least on later models, but the one we bought didn't have them. I have never actually seen one with LED headlights, though. There are apparently other options that are also not on all cars. For example, while our CT has full power seats, it does NOT have the seat memory option for the driver's seat. I believe that's because our CT has the NuLuxe synthetic leather, and you only get the memory option if you have the genuine leather package (which, as a vegan, my wife would not want to have).

I had actually installed LED headlights from SuperBrightLEDs, both low and high-beam, in both the CT and my wife's mom's 2013 Toyota Corolla. I had even installed them in my wife's previous car, a 2015 Honda Fit. However, shortly after, I had read that that's not a good idea, because the headlight housings are designed around the dispersal pattern of halogen bulbs, which is different from that of LED bulbs. So when you put an LED bulb into a housing designed for halogen, the result is that you get a "wall of light" that blinds oncoming drivers, but actually does not project down the road nearly as well as the halogens, so it becomes a safety issue on both fronts. With that in mind, I put the halogens back and returned the LEDs to SBL.

I'm excite though! I'll definitely post more once I get everything and introduce myself in the main forum thread.
Sounds good! Look forward to seeing some pictures. :)
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I can't speak for the particular bulbs you are looking at; however, my experience with bulbs with built-in resistors in general was not good on the CT. I tried several different types, and they all seemed to eventually suffer from hyperflashing despite the resistors. It would happen after the signal was going for a while, e.g. parked with hazards on, or at a long light making a turn. I suspect that the resistors inside were probably heating up too much and their resistance was dropping, making the car think that a bulb was burned out. (They wouldn't hyperflash when using hazards, because the hazard setting doesn't pay attention to resistance. But I could, say, run the hazards for a while, then switch to a left or right signal, and it would immediately start hyperflashing.)

I found that the best solution was to replace the flasher module with an LED-compatible flasher. I finally happened across the right information, which told me that the flasher IS replaceable. It's just REALLY hard to get to. But once I finally got to it and loosened it from its home, I was able to replace it, and then rather than putting it back where it was, I just secured it to another bundle of wires that was much lower down and easier to reach. And by doing this, I was able to use regular LED bulbs without resistors, much cheaper than those with built-in resistors.
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