I searched around a bit and didn't find much information on this. So after tearing my vehicle apart trying to find the turn signal relay, I figured I would post some instructions. It's easy, takes about 15 minutes and only requires a phillips head screwdriver, a 10mm socket, and maybe a small flathead screwdriver or pocket knife.
I swapped my OEM relay out on my 2015 LC for a Diode Dynamics SmartTap CF18 Flasher Relay, because I wanted it to do the automatic "intelligent" 3-blink turn signal for lane changes. In other words, what is on most newer cars, that allows you to slightly tap the turn signal stalk and it makes the turn signal flash 3 times (perfect for lane changing). I know some hate this feature and some love it. I personally am used to it from my 2017 Tacoma and 2018 Highlander, so wanted it in my 2015 LC.
Instructions:
1. Remove bottom black plastic kick panel on driver's side. It takes 2 phillips head screws.
2. Remove middle black plastic panel above the kick panel and below the steering wheel (maybe people would call this a knee panel?). It takes removing two 10-mm bolts. On my vehicle, you need to flip down two little plastic covers to expose the bolts. I used a small screw driver or pocket knife and those covers pop down like little doors to expose the bolts. They are fragile and I broke one, so be careful. Once the bolts are removed, you pull it towards you and then upward.
3. Now you need to find the relay. Here is a picture pointing it out. A trick is to turn the vehicle on (not the engine) and turn on the turn signal and you will hear the relay clicking. If you put your hand on it, you'll feel it vibrate with each click. That's a good way to ensure you're removing the correct plug.
This is what it looks like on my 2015:
4. Unplug the OEM relay. The old relay itself is secured to the car, so all you need to do is unplug the harness from the relay. That's just a matter of pushing in the little pin on the right and pulling the harness toward yourself until it unplugs. Here is a close-up.
5. Now you should be able to plug in the new flasher relay to the unplugged harness. After plugging it in, I ended up using a zip-tie to secure the new relay and harness to an adjacent harness.
Here is a photo of the new relay zip-tied on. It's the tan colored relay. Note that I removed the panel of buttons/switches (as you see in this photo), but that was not necessary. For reference, I also removed all the steering wheel trim (upper/lower), and that was also unnecessary. You live and learn.
6. Test your turn signals and hazards to ensure everything works before buttoning your car back up.
7. Put your car back together.
Here is an instruction manual for the CF18. Changing the settings, like number of flashes or how the hazards work, is really easy.
I got it for about $60 on amazon. Hope this helps someone.
I swapped my OEM relay out on my 2015 LC for a Diode Dynamics SmartTap CF18 Flasher Relay, because I wanted it to do the automatic "intelligent" 3-blink turn signal for lane changes. In other words, what is on most newer cars, that allows you to slightly tap the turn signal stalk and it makes the turn signal flash 3 times (perfect for lane changing). I know some hate this feature and some love it. I personally am used to it from my 2017 Tacoma and 2018 Highlander, so wanted it in my 2015 LC.
Instructions:
1. Remove bottom black plastic kick panel on driver's side. It takes 2 phillips head screws.
2. Remove middle black plastic panel above the kick panel and below the steering wheel (maybe people would call this a knee panel?). It takes removing two 10-mm bolts. On my vehicle, you need to flip down two little plastic covers to expose the bolts. I used a small screw driver or pocket knife and those covers pop down like little doors to expose the bolts. They are fragile and I broke one, so be careful. Once the bolts are removed, you pull it towards you and then upward.
3. Now you need to find the relay. Here is a picture pointing it out. A trick is to turn the vehicle on (not the engine) and turn on the turn signal and you will hear the relay clicking. If you put your hand on it, you'll feel it vibrate with each click. That's a good way to ensure you're removing the correct plug.
This is what it looks like on my 2015:
4. Unplug the OEM relay. The old relay itself is secured to the car, so all you need to do is unplug the harness from the relay. That's just a matter of pushing in the little pin on the right and pulling the harness toward yourself until it unplugs. Here is a close-up.
5. Now you should be able to plug in the new flasher relay to the unplugged harness. After plugging it in, I ended up using a zip-tie to secure the new relay and harness to an adjacent harness.
Here is a photo of the new relay zip-tied on. It's the tan colored relay. Note that I removed the panel of buttons/switches (as you see in this photo), but that was not necessary. For reference, I also removed all the steering wheel trim (upper/lower), and that was also unnecessary. You live and learn.
6. Test your turn signals and hazards to ensure everything works before buttoning your car back up.
7. Put your car back together.
Here is an instruction manual for the CF18. Changing the settings, like number of flashes or how the hazards work, is really easy.
I got it for about $60 on amazon. Hope this helps someone.
