DIY | Enabling the European/10 Series 6-pin HID LED Low-Power with Headlights for $5

[Siege]

I purchased my 2013 FR-S 10 series at the end of October and immediately noticed that the LED DRL strip did not light up when the headlights were on. After doing research, I discovered that the rest of the world gets 7-pin headlights that turn on the LED's dim when the headlights are on.

Here's how to replicate this feature on Euro/10 Series headlights:
1. Purchase 400 ohm, 10W resistor. There are a lot of options here depending on how you want to mount it.

If you want to mount it to the body then you can get chassis mount resistors like:


Or you could get a simple ceramic resistor like below and strap it to the harness:


2. Solder wires to the lugs/leads of the resistor ensuring you have enough length to reach from where you want to mount the resistor to the RH headlight connector.

3. Tap into #1 and #5 on the RH headlight connector. #1 is brown and #5 is red and they are the two wires on the end of the connector facing the middle of the car. You can either unpin the connector and wrap the ends of the wire around the pin and reinsert for a completely reversible installation or tap into the wires manually.

Here is what it looks like when you connect the wires to the pin.



4. Mount resistor wherever you want.

5. Profit!

I found that the 400 ohm resistor was the perfect level of dimness for myself but feel free to experiment with lower ohm resistors to get the level of brightness you want.

Finally a shitty cellphone picture of the headlights with LED's lit up.

This is with 500 ohm of resistance.



These are with 400 ohm of resistance:

[Luis_GT]

Nice job... I've been leaving this mod in the back burner, I planned on using a variable resistor on mine.

[Siege]

Thanks! Yup you could very easily use a rheostat in place of a fixed resistor if you wanted to adjust the brightness from the cabin.

[Greenhorn]

Originally Posted by Siege

Thanks! Yup you could very easily use a rheostat in place of a fixed resistor if you wanted to adjust the brightness from the cabin.

Does this dim the DRLs only when the HIDs are switched on, or all the time?

[twag4]

Originally Posted by Greenhorn

Does this dim the DRLs only when the HIDs are switched on, or all the time?

Just when HIDs are on. They are full bright when HIDs are off.

[Luis_GT]

Originally Posted by Siege

Thanks! Yup you could very easily use a rheostat in place of a fixed resistor if you wanted to adjust the brightness from the cabin.

I think you have a typo on the guide, I think you meant 50 ohm instead of 500 ohm, I tested a 100ohm resistor and they where almost off... tested with a 50 ohm resistor and they look perfect!

I'm also using a diode so that current doesn't backflow to the #5 pin.

[Siege]

Originally Posted by Luis_GT

I think you have a typo on the guide, I think you meant 50 ohm instead of 500 ohm, I tested a 100ohm resistor and they where almost off... tested with a 50 ohm resistor and they look perfect!

I'm also using a diode so that current doesn't backflow to the #5 pin.

Nope, I'm definitely using a 500 ohm resistor (actually 5 100 ohm resistors so I could add and remove to get the desired brightness).

Although I definitely have mine dim at 500 ohm. In the dark with the headlights on they are lit up just enough to be visible but not project light.

Please post a picture with the 50 ohm so we can compare.

Also, great idea with the diode! I'll incorporate that and update the first post.

[Siege]

I just went outside and took additional pictures in the different cycles.

[Luis_GT]

Originally Posted by Siege

Nope, I'm definitely using a 500 ohm resistor (actually 5 100 ohm resistors so I could add and remove to get the desired brightness).

Although I definitely have mine dim at 500 ohm. In the dark with the headlights on they are lit up just enough to be visible but not project light.

Please post a picture with the 50 ohm so we can compare.

Also, great idea with the diode! I'll incorporate that and update the first post.

in series or in parallel?



Here's mine with just the 50 ohm

[Siege]

Series. If they were wired parallel the total resistance would be 20 ohm.

Thanks for the pictures!

You said when you tested that the 100 ohm resistor on your car the LEDs were significantly darker? Would you say they were darker than my pictures?

I'll try a 100 ohm resistor tonight and get a picture to compare.

[Luis_GT]

Originally Posted by Siege

Series. If they were wired parallel the total resistance would be 20 ohm.

Thanks for the pictures!

You said when you tested that the 100 ohm resistor on your car the LEDs were significantly darker? Would you say they were darker than my pictures?

I'll try a 100 ohm resistor tonight and get a picture to compare.

I know... that's why I asked if it was in series or parallel... to me the 100ohm made the LED's to dim, but then again, I was comparing it during the day, not at night.

with the 50 ohm resistor the LED's are still simmer than the headlights so it shouldn't cause any issue to oncoming traffic.

[#944_10_Series_FRS]

Subscribe to see the end result... Very interest.

[Greenhorn]

When I did mine I bought 560, 470, and 320 ohm resistors just so I could try a few to get the brightness right. Put the 560 in and I could barely see them, even with the lights in the garage off. Went straight to the 320, and that's still less bright than I'd like them to be. So mine are definitely less bright than the OP's and more in line with Luis's.

Also, the DRL on the passenger side, where I put the resistor, seems brighter than the one on the driver's side... I really don't know that much about electricity/physics, but this doesn't seem like it should be happening. I'm going to get a lower impedance resistor and add a diode. Hoping the lower impedance and higher voltage will make the difference either go away or less noticeable.

[Greenhorn]

Here's a shot of my headlights with the 320 ohm resistor. It's hard to tell, but the passenger side DRL is a little brighter. And yes, it started snowing today. Come to find out my Blizzaks work pretty well in empty parking lots...sideways...