2017~2025: CX-5 LED Turn Signal Conversion

[David Paul]

All the pictures enclosed are the right side of the vehicle. This side took me about an hour as everything was hit and miss as far as placement of the resistor, attachment of wires, etc....

The left side took me about a half hour and was basically the same as the right side.

I soldered all joints, covered them with tape and bound them together with small zip ties for extra security.

The resistors (50W 6ohm) are screwed to the metal body of the vehicle so as to help dissipate heat and they don't touch any wiring or plastic.

I used the same Amber LEDs for all four corners. Link is enclosed. Obviously, you can use any vendor you choose. Just make sure you use quality LEDs and always bench test them before installation.

https://www.ebay.com/itm/332453339267?_sp=p2488212.m41214.l9765&_trkparms=itemid:332453339267

Once you have the taillights removed, you will see that all the pictures make sense. Very simple mod.

If you don't know how to wire a resistor, just do a google search.

The LEDs are about the same brightness as the OEM incandescent bulbs but the "instant on" of the LEDs make them much more noticeable and attention getting.

Now I have all the interior and exterior lighting of my CX-5 converted to LEDs. A couple of years ago, I did the same to my 16 MX-5 GT.

One more thing. Based on the specific LED product that I used on all four corners, I did not have hyper flash with just the rear LEDs installed. I knew that would change as soon as I installed the front LEDs. However, for those of you who don't want to work with resistors right away, you can have a "Half Conversion" if you so choose. Again, that is with the specific LEDs that I used. It is possible that other brands may act differently. I have seen this occur with some of the ND, MX-5s on that forum. All LED products are not equal.

The following pictures are in no particular order. They are just for reference and familiarization of this project.

 

[yrwei52]

Nice write-up with pictures!

May I present some comments here. IMO using electrical tape to protect soldering joint is not safe although you did use zip tie for extra security. Electrical tape will be loosing its bounding capability over time especially in the hot or cold environment. It's not safe to use it for permanent purpose. Usually we use "electrical heat shrink tube" instead of tape for best long-term protection to the soldering joint.

Secondly, for US CX-5 the front turn signals use 7444NA dial-filament amber incandescent bulbs (to serve both turn-signal and parking light) but the rear turn signals use 7440NA (although our owner's manual falsely specified 7443NA dual-filament bulb) single-filament amber incandescent bulbs. We should select those 7440/7444 LED series carefully making sure they support both dual and signal filament bulb functions. More offen people use amber/white "switch-back" LED at front, to get much better effect to distinguish the appearance between the turn signal and parking light during the night.

Unfortunately 7440 series LEDs with build-in resister for plug-and-play do not support amber/white switch-back function at this time.

I hope Mazda can spend some money using LED turn signals on CX-5 from factory like new 2018 Mazda6. I hate to use big resisters which would generate lots of heat and waste plenty of energy.

 

[David Paul]

Nice write-up with pictures!

May I present some comments here. IMO using electrical tape to protect soldering joint is not safe although you did use zip tie for extra security. Electrical tape will be loosing its bounding capability over time especially in the hot or cold environment. It's not safe to use it for permanent purpose. Usually we use "electrical heat shrink tube" instead of tape for best long-term protection to the soldering joint.

Secondly, for US CX-5 the front turn signals use 7444NA dial-filament amber incandescent bulbs (to serve both turn-signal and parking light) but the rear turn signals use 7440NA (although our owner's manual falsely specified 7443NA dual-filament bulb) single-filament amber incandescent bulbs. We should select those 7440/7444 LED series carefully making sure they support both dual and signal filament bulb functions. More offen people use amber/white "switch-back" LED at front, to get much better effect to distinguish the appearance between the turn signal and parking light during the night.

Unfortunately 7440 series LEDs with build-in resister for plug-and-play do not support amber/white switch-back function at this time.

I hope Mazda can spend some money using LED turn signals on CX-5 from factory like new 2018 Mazda6. I hate to use big resisters which would generate lots of heat and waste plenty of energy.

My use of electrical tape in this situation is only temporary. Generally in this tight of an area, I use several coats of liquid tape but when I opened the jar, I found it mostly evaporated. Sooooo, the next best thing was what I did.

I have quite a bit of various sizes of shrink tubing but due to the very short wires involved, I prefer to use the liquid tape as soon as I get some. Due to the short pieces of wire, the shrink tubing will also be very short and will not shrink enough on the ends to be water tight. For now, with the zip ties holding everything together, the tape is very secure and not likely to come off anytime soon unless I remove it. The main thing was to just keep the hot and ground wires from touching each other and anything else that could cause a short.

I agree with you regarding the heat generated by the resistors. I don't like it either but as long as they are bolted or screwed down tightly to the metal body, the heat dissipates rather quickly. But in the mean time, a persons gotta do what a persons gotta do.

Yes, I am aware of the fact that the front bulbs have dual elements as did my 16 MX-5. I intentionally went with the single color LED because as far as I know, I do not have the option on either of my Mazdas for parking lights. If I do, I certainly have never been able to turn them on. What am I missing here? Of course, it is a very simple matter of getting front replacement LEDs that are 2 colors if I find it necessary or useful. Mazda engineers finally made it very easy to change the front bulbs and to a slightly lesser degree, the rear tails as well.

Thanks for the tips.

 

[yrwei52]

Yes, liquid tape is a better option than heat shrink tube for soldering joint as its waterproof.

And yes, your GT disabled the front parking lights on both 7444NA amber bulbs which are designed only for US CX-5. So for gen-2 CX-5 GT, getting an amber/white "switch-back" LED for turn signal is irrelevant.

Although 2017 CX-5 owner's manual says the front turn signal/parking light uses dual-filament 7444NA bulb, but the pictures I took earlier on a 2017 CX-5 GT suggests otherwise:

Light switch at parking light position:

Light switch at headlight on position (low beam):

LED Signature accent strips added on GT partially block turn signal and LED DRL location on Touring/Sport. And you can see how small and dim the turn signal is on GT comparing to Touring/Sport when the headlights are on!

The LED DRL space on Touring/Sport between headlight and amber parking/turn signal looks like unused on GT.

View attachment 217137 View attachment 217136

Here are some pictures from 2017 CX-5 Touring showing whenever DRL function is on, both LED DRLs and LED low-beam headlights are simultaneously on! You can imagine how GT DRLs work by replacing Touring LED DRLs with GT's LED Signature DRLs.

Here's what the front lights look like when light switch is at parking light position without DRL function when car is in stationary:

Here's what the front lights look like when light switch is at headlight-on position without DRL function when car is in stationary:

Finally for 2017 CX-5 Touring the high-beam is from the same LED cell for the low beam in the projector, and use a shutter to control them like 2015 bi-xenon HID. For 2016 LED headlights we have a separate LED cell at inner side of the low beam LED dedicated for high beam only.


View attachment 216512 View attachment 216513 View attachment 216515 View attachment 216514

 

[gazelle]

What's your opinion about tapping, as in LED Resistor Kit (pair) ?
Is tapping safe / durable enough?

 

[Chocolate]

What's your opinion about tapping, as in LED Resistor Kit (pair) ?
Is tapping safe / durable enough?

No need to solder or tap, there are easier ways. I'd either get plug and play 7440 LEDs with resistors built in like this https://www.amazon.com/dp/ (commissions earned) (currently unavailable, I got these a few years back for the front signals and they are very bright, and plug and play. You can find similar on Amazon).

Here's the before and after.

LEDs

Discover the magic of the internet at Imgur, a community powered entertainment destination. Lift your spirits with funny jokes, trending memes, entertaining gifs, inspiring stories, viral videos, and so much more from users like powerhawk5000.

imgur.com

Or use an adapter like this with a regular 7440 LED bulb, https://www.amazon.com/dp/ (commissions earned) no soldering/tapping required. I prefer the look of red LED signals in the rear, so I used an adapter with red 7440s in the rear. (I already had them in a previous vehicle that used the 7440 standard so I just transferred them over). I mounted the resistors to the steel body panel next to the light.

Hope this helps! One of the first thing I did when I got my CX-5 a few years ago was convert the incandescent bulbs to LED.

 

[gazelle]

I don't like the idea of having multiple extreme heat emitting resistors sitting inside the light. If you replace all bulbs in rear light that would be three per light, correct?

I'm looking at the adapter, thanks for the hint

 

[Chocolate]

It's got a big aluminum heat sink. I've been using it for the last 3 years in both hot and cold temps, no issues. Same as the set in the rear with resistors.

Rear reverse and license plate bulbs are LED for 2019+. For 17+ GT and above trims, the taillights are already LED units so you'd only need to replace the turn signals in the rear.

It is an inexpensive mod that improves the look of the car.

 

[gazelle]

you'd only need to replace the turn signals in the rear.

Thanks. But what about brake lights? Are they the same as turn signals but red? And if they need replacement do they require resistors as well?

 

[Chocolate]

Thanks. But what about brake lights? Are they the same as turn signals but red? And if they need replacement do they require resistors as well?

There are two versions of taillights on 17-21 models. One incandescent which uses a dual filament 7443 bulb for running and brake lights, the other LED for GT+ trims. Your GTR already has LED running and brake lights.

 

[RedBaron]

Thanks. But what about brake lights? Are they the same as turn signals but red? And if they need replacement do they require resistors as well?

In theory, no, they don't require resistors. I put Phillips LED bulbs as brake lights in my 2019 and initially it worked fine. However, a few months later I started having issues with the Smart City Braking and cruise control, sometimes it would throw errors and disable cruise. I even got pulled over at one point because the brake lights (apparently) kept periodically flashing (cop thought something was wrong). I took it to the dealer a few times for this. At first they blamed it on my aftermarket remote start, then on LED lights. I put the original bulbs back in and no issues (over a year) since!

So, YMMV. It may have been the particular bulbs. Who knows?

 

[chickdr]

I don't like the idea of having multiple extreme heat emitting resistors sitting inside the light. If you replace all bulbs in rear light that would be three per light, correct?

I'm looking at the adapter, thanks for the hint

Hi there. I too have a '21 GTR and swapped all bulbs to LED (front turn signals, rear turn signals, all interior bulbs). I love the finished look. Rear turn signals are way brighter with LED (fronts are not as dramatic, but still better). You can use bulbs with built in resistors on one end (front or rear) but the other must have external resistors or you will get hyper flashing. This seems to be a manufacturer to manufacturer variation as my 20 Frontier was fine with built in resistors front and rear. As already said, all other external bulbs are LED from the factory. I have had zero issues with my LEDS. I had them in my '19 GT as well and they did fine, but I did not have the front turn signals on that car.

 

[gazelle]

Just verified that one resistor per side is not enough for diodedynamics HP11 so I need another couple
I've got this adapter so far (that I had to cut to fit) https://www.amazon.com/dp/ (commissions earned)
I plan to get tapping resistors and I want to tap them into the adapter above that I've already installed.
Shouldn't cause issues and looks like a clean install doesn't it?

Bonus question: if hyperblinking is to indicate the bulb went out, how do I know if LED went out when there are two resistors? Do LEDs with built-in resistors fry along with resistors and thus more safe?

 

[chickdr]

I would suspect there would be hyperflashing if a bulb goes out once if you have the resistors in place. I would not be using the LEDs you purchased if a single resistor isn't doing the job. I would contact the company and ask for a bulb that either has a built in resistor, or one that works with a single external one. You asked about the number of bulbs to replace in the rear light (I missed that question). You only have one incandescent bulb per side (the turn signal) in both front and rear assemblies since you have a GTR.

 

[RedBaron]

I would suspect there would be hyperflashing if a bulb goes out once if you have the resistors in place.

Nope.

Bonus question: if hyperblinking is to indicate the bulb went out, how do I know if LED went out when there are two resistors? Do LEDs with built-in resistors fry along with resistors and thus more safe?

You won't. The resistors are in parallel with the LEDs, so if the LED dies, the resistors are still shunting the current, leading the BCM to think the bulbs are still intact. The good news is that the LEDs (should) last for 1000's of hours - probably longer than you keep your car - but you should manually check every few months, just in case.

 

[Chocolate]

It might be easier and more cost effective to use bulbs with built in resistors first. Those Diodedynamic bulbs list for $60, then another $15 for an adapter, when you can get them built in for $24 on Amazon. https://www.amazon.com/dp/ (commissions earned)

You could still use the adapter if you want to update the front as well, per post 12 above.

 

[gazelle]

Reviews of the amazon one say it starts to hypeflash after 2-5 minutes... I actually looked at numerous options before I settled on Diode Dynamics as it's a US based company that responds to inquiries and lists convincing data. Something tells me it's expected that a LED bulb that is not super bright requires a resistor per bulb and not per side, will confirm with them.

I was mostly interested if it was ok to tap another resistor into that adapter...

 

[chickdr]

Reviews of the amazon one say it starts to hypeflash after 2-5 minutes... I actually looked at numerous options before I settled on Diode Dynamics as it's a US based company that responds to inquiries and lists convincing data. Something tells me it's expected that a LED bulb that is not super bright requires a resistor per bulb and not per side, will confirm with them.

I was mostly interested if it was ok to tap another resistor into that adapter...

This is actually common with LEDs as when they get hot (they can hyper flash) but how often to you actually use your signals for more than 2-5 minutes? They also revert to normal once they cool down. I can tell you mine have never hyper flashed in the 3 yrs I have been using LED's in my CX-5s..

 

[Chocolate]

This is actually common with LEDs as when they get hot (they can hyper flash) but how often to you actually use your signals for more than 2-5 minutes? They also revert to normal once they cool down. I can tell you mine have never hyper flashed in the 3 yrs I have been using LED's in my CX-5s..

Mine have not hyperflashed in the last 3 years either.

Even if you were leaving your hazards on for an extended period (and draining the car battery while doing so) they will still function, even if in a hyperflash mode.

It's also possible one bulb type will require separate load resistors on one side when used front and back, and another will not. It's no big deal to order a bulb on Amazon and return if it doesn't work.

Just sharing my experience and opinion. If no need to over complicate wiring, why go that way. Seems to me you'd want fewer points of failure. Occam's razor - Wikipedia

 

[gazelle]

Well, it depends on what you call a point of failure. An "active fan" in amazon bulb vs having two resistors per side is tough choice... I tapped in the second resistor, so far so good

Thanks for your recommendations