LED History

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History of my LED & Fluorescent lighting upgrades

The stock incandescent light bulbs in the doors and interior get hot and draw quite a bit of current.

I've found that the new white LEDs that you can buy these days put out a lot of light - nothing like the original red LEDs.

On measuring the current draw of just one of the original door lights: 0.25A, it's quite obvious that if you leave doors ajar while camping and don't turn off all the interior lights you will suck the battery down over a few days.

The first step to reducing the current draw and improving the light output was to retrofit the bulbs in the door courtesy lights. I used a string of 3 white LEDs in series with a series 100ohm resistor. The current draw using the LEDs is only 0.025A for the string of three 'bulbs', a reduction by 10 fold over the incandescent lights. The very noticeable improvements with the LEDs are that the light is brighter, the heat is gone and the light is very WHITE.

You can get an idea how bright the LEDs are - with your naked eye the three individual LED sources are very noticeable, but the camera just blurs them all into a single source.

The following picture shows the original dome light bulb at the top. The middle and cargo dome lights use the same bulb, a 10W unit that draws about 0.75A - gets quite hot! Below the bulb is my original prototype LED based replacement. It was made of two strings of 3 LEDs each with a 120 ohm series resistor (total current draw: 0.05A). The two strings were in parallel and I soldered tabs at each end so that the LED replacement bulb would 'plug' into the existing socket with no modifications needed. The light output was very similar to the original incandescent bulb, other than being very white.

The next step in upgrading the interior lighting was to install an efficient fluorescent in the rear most cargo area for camping. I chose an 8W unit with a highly efficient inverter - I was impressed to measure about 350mA draw for a quoted output of 400 lumens. I wanted the light to be either switched or automatic when the rear hatch was opened. To get power to the light I spliced into the rear cargo dome light wires (Blue is +12V and Red is switched GND). The rear dome can be easily removed and the wires accessed by undoing the 4 screws that are under the diffuser lens (just unclips). I then had to fish the new pair of wires to the rear area where the fluorescent was going to be installed. You can see from the picture the direction the new wires were routed. Don't worry about the wires not having enough room - there is a reasonable gap between the headliner and the actual roof.

The following picture shows the installed light (you can see the 6 lit up white LEDs in the dome). The picture also shows the 3 clips that must be popped out to loosen the headliner. I used a screwdriver to pry the clips out. To loosen the headliner you have to remove a bunch of other hardware - see the next picture.

This picture shows all the other bits that need to be removed to be able to gain enough access at the rear most section of the headliner to fish the new wires out and to fasten the fluorescent fixture. You have to do the following steps:

Undo the rear seat belt top bolt on each side.
Pull off the weatherstrip on both sides sufficiently so as to be able to remove the plastic trim. There is one clip that holds each trim piece - where it says 'pop clip' in the picture. You will have to pop two clips on the lower plastic trim to be able to slide the trim piece out.
With the trim piece remove from both sides you can now remove the u-channel trim piece - this holds the rear lip of the headliner to the roof.
Remove the two bolts for each handle and remove the handles.

Now you should be able to lower the rear part of the headliner a couple of inches to get the access you need. Be careful, the headliner is bonded to a very thin plastic material - easy to crack!

To mount the fluorescent light fixture I just drilled a few holes and used tie wraps - the light weighs very little. I also made a hole to pull the wires through and solder them to the pigtails that came with the light.

Luxeon Time - I've seen the light....

Time to test the first assembled Luxeon Dome light - the best time of course is at night.

It's hard to convey how bright the Luxeons are but here a few shots. These pictures were taken with an Olympus 2040Z digital camera. This is the view from the front seats of just how much light the middle row dome is putting out.

A view of the middle row seating lit by just a single Luxeon LED. The light output is very similar to the 8W fluorescent I have in the rear - quite impressive!

This is the view of the interior from the rear of the vehicle. The middle row dome has a Luxeon LED, the rear dome has an array of 6 conventional white LEDs. The Luxeon is also putting out a nice warm white light compared to the more 'cold' white/blue of the LED array (the green tinge really isn't there - the auto white balance on the digital camera is 'confused'). The array of 6 white LEDs was nicer than the stock 10W incandescent since all it's light output was directed downwards, but, the Luxeon is MUCH nicer - the 80 interior is finally WELL lit!

You can see how bright the front Luxeon is compared to the 6 LED array in the rear by the over exposed area of the picture. As soon as I assemble another Luxeon light (and don't have someone to ship it to), the rear will be upgraded as well!

2006 - Time for LED technology for the old rear Fluoro

After a few years, the old fluoro tube gave up the ghost. So, instead of locating a replacement tube I decided to gut the old electronics, upgrade to 3 Luxeons and put in one of my nFlex microcontroller based drivers.

First step was to install the 3 1W Luxeons and open up the housing to allow all that great light to escape from the housing. You can see the nFlex driver in the bottom right of the housing. I glued a clear acrylic plate on the inside so the housing is nominally dustproof when closed up.

I also added a second switch that allows me to adjust the light output. I have also turned on the auto-sleep/dim feature of nFlex - so it will automatically dim and turn off if the tailgate is left open all day.

Yes, good old tiewraps hold the fluoro assembly up. It weighs so little that it's an expedient way to fix the unit to the headliner. I used the same scheme when the fluoro tube was in there - and after several years I see no issues.

The final result, light mounted and the Luxeons set to their lowest output level via the nFlex driver. It's day time of course.

Late dusk and finally a chance to try out the new light. Looks pretty bright to me compared to the single Luxeon dome module.

In comparison to the original fluoro, it draws about 2/3 the current and definitely puts out a LOT more light and based on the longevity of the Luxeons it won't be burning out any time soon!

Another thing I noticed from a long camping trip to oz is that the LEDs attract very few bugs at night versus fluorescent lighting.