-   EcoModding Central (
-   -   My LED tail light conversion (

BrianAbington 02-11-2009 09:58 PM

My LED tail light conversion
I have converted my parking lights/brake lights to on to find out why and how.

Shortly after I was given my car the dash lights and parking lights went out. Since these both share a common turn on point on the steering column switch I know that its either the switch itself, or the circuit in the main lighting relay that controls them both.

I really do not want to remove the steering wheel and take apart my steering column, I also don't want to pay $90 for a relay only to find that it did not fix anything. So I decided to hook up the parking lights to an "ignition on" power source.

I decided to hook them up to an ignition source because of the fact that my hypermiling means I tend to drive slower than everyone else...lights on for safety....right?

I have also wanted to convert my lights to LEDs to relieve the charging system.

Here are the lights in original condition
yes I know the car needs to be washed

I looked at the LED lights that all the auto parts stores in town had. They all had huge housings or big dorky chrome bezels and only 4-10 LEDs in them. So I had a thought that I should go check out the truck stop on the edge of town.

When I went there I found these:
These are used to update the lights on semi trailers. 40 Leds per housing and they are prewired with a 3 wire harness.
They are really really bright in the "parking light" mode but the "Brake light" mode is unbelievable.
I know the picture shows them in the oven. I was originaly going to try to heat them up and pry them open to mount them inside the taillight housings. I couldn't get them apart so I went a different route. I just forgot to take a different picture of the housing before they were mounted.

These LED lights as you can see in the picture have no mounting points, so I wanted to modify the OEM housings to fit them in through back of the OEM lenses.
I traced the LED lens onto the OEM lens. I then drilled a large hole at both ends of the traced oval, and cut the OEM lens with a key hole saw and ground down the edges with a grinding stone.
If you do this yourself use a fresh blade for the second lens. My blade was pretty dull after the first one and it actualy snagged and shattered the lens as I was cutting. Its still a tight fit but it has a bit of a gap...but that will be covered up later.

I covered the turn signals and the plastic surround with tape and painted the taillights a semi gloss black.
I will eventualy convert the turn signals to Leds in the same fashion as these and will paint the turn signals at that time.

The factory tail lights are really unique. They have a large ovalish panel that removes from the back of the housing. This plastic pannel has a harnes wired into it and two light bulbs mounted infront of chrome reflectors. (will take a pic of that tomorroe)

The new led housings fit perfectly through this opening, so I covered the edge of the housing that would contact the back of the lense and slipped them in though the opening.
You can also see the gap around the light were the saw cracked the lense. They make cosmetic mounting gaskets for these housings that I will eventualy put over this gap.

It was dark by the time I finished this work so I will finish up in the morning. Have some wiring to do and will reinstall the housings and post up some finished pictures and then some day and night light pictures.

cfg83 02-12-2009 12:35 AM

Binger -

This is really cool. I have to think that LEDs for truckers are going to be more reliable and brighter like you say. In a way, your solution will be form-follows-function.


Piwoslaw 02-12-2009 02:59 AM

That's neat:) I'm coming around to replacing some of my lights with LEDs and adding DRLs up front.
Binger, have you checked how much less electricity the LEDs need? And are there laws about how bright car lights can be? You don't want to blind the driver behind you.

i_am_socket 02-12-2009 09:00 AM

Very nice so far :thumbup:

MetroMPG 02-12-2009 09:43 AM

Do you have figures for the OEM bulb wattage vs. the LED cluster that's replacing them?

BrianAbington 02-12-2009 11:15 AM

The factory setup uses two 1157 bulbs for the parking/brake assembly. From what I have read online an 1157 bulb with a single filimant lit is 2.1amps and with both filaments illuminated it draws about 2.7 amps.
According to the original plastic panel for the taillight housing the bulbs put out 5 watts of light each.

So lets do some math here... remember theres 2 bulbs per housing...
parking lights = 8.4 amps
Brake lights = 10.8 amps
combined wattage= 20 watts

The led housings draw about .10 amps for the brightest mode.
so that is .4 amps...that is a 10.4 amp drop.

All i can find for light output is that they have "superior light output".

So they do make a drastic difference in power draw.
Also the nice thing is that instead of 4 amberish colored incandescent bulbs shining through a white difuser and a red lense these are 40 super bright leds shining thorugh a clear red lens

Daox 02-12-2009 11:28 AM

I think ya got amps and watts messed up and intermingled in your calculations there.

None the less, nice mod. Take pictures afterwards with them lit up!

BrianAbington 02-12-2009 11:34 AM

i could be wrong...but everything I found said that 1157s pull 2.1 and 2.7 amps each depending on id one or both filaments are lit up.

dosn't matter...they are brighter, safer, and pull less power.

Ill try to take some pics tonight.

hypermiler01 02-12-2009 12:52 PM

For the turn signals, I would just buy those LED bulbs that fit in the original socket.

BrianAbington 02-12-2009 04:01 PM

I thought about that...but they have trailer lights that will fit and they have 40leds as well :)

Pics will be up tonight.

All times are GMT -4. The time now is 02:47 PM.

Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2021, vBulletin Solutions Inc.
Content Relevant URLs by vBSEO 3.5.2
All content copyright