LED interior lighting project

[MountainManJoe]

Here's a sneak peak of what I've been experimenting with ...

These will be the dome lights:

They are brighter than they look in this photo due to the exposure setting on the camera, but still not as bright as I had hoped (and they advertised).

Further testing and comparisons to come later.

This is what I wanted for the map lights:

This is a 5 Watt LED and it's stinkin' bright. I had purple spots in my vision just from working around it. The first time I powered it up (to about half capacity), it started to smoke, so I bolted it to that chunk of aluminum heatsink you see in the photo. Still, after a few minutes, the heatsink was too hot to touch with my bare hands (again limited to only 0.3A) , so I don't think I'm going to use it. I'll try the 1W and 3W versions and see if I can get the heat issues in check.

The light seemed a bit too spread out for a map light. I like how the OEM ones don't distract the driver. I grabbed my jewelers loupe and placed it in front of the LED ...

... and got a nice spot beam. It's a bit too focused though. There are many different kinds of collimators available for these bulbs on eBay, so it's just a matter of finding the right focal length.

[MountainManJoe]

These eBay high power LEDs are a nice fit for the Astro's map light pods.

[photo_van]

Alright, keepin' an eye on this.

[AquaAngel]

I did the same thing in my van as the regular bulbs that lits the interior wasn't as bright.

So i bought the Squared board LED and used some RTV sealant to hold them on the original lens and they are really bright. Love it.

Keep on the good work

Here's a sneak peak of what I've been experimenting with ...

These will be the dome lights:

DSC02045.JPG

They are brighter than they look in this photo due to the exposure setting on the camera, but still not as bright as I had hoped (and they advertised).

DSC02041.JPG

Further testing and comparisons to come later.

This is what I wanted for the map lights:

DSC02052.JPG

This is a 5 Watt LED and it's stinkin' bright. I had purple spots in my vision just from working around it. The first time I powered it up (to about half capacity), it started to smoke, so I bolted it to that chunk of aluminum heatsink you see in the photo. Still, after a few minutes, the heatsink was too hot to touch with my bare hands (again limited to only 0.3A) , so I don't think I'm going to use it. I'll try the 1W and 3W versions and see if I can get the heat issues in check.

loupe.jpg

The light seemed a bit too spread out for a map light. I like how the OEM ones don't distract the driver. I grabbed my jewelers loupe and placed it in front of the LED ...

DSC02050.JPG

... and got a nice spot beam. It's a bit too focused though. There are many different kinds of collimators available for these bulbs on eBay, so it's just a matter of finding the right focal length.

[MountainManJoe]

Well I found out why my LED was overheating... Chinese eBay sellers trying to pull a fast one on me (again). They sent me a lower power LED, so I was basically overdriving (cooking) it. I came to this conclusion after I noticed the forward voltage didn't correspond to the (highly inaccurate) data sheet they sent me. I politely brought this to the sellers attention, so they offered to send me a replacement. Here they are side by side ...

As you can see, the 5W is much larger than whatever the other one is. It also runs much, much cooler.

Unfortunately, the replacement LED was defective ...

eBay is very cheap, but requires a lot of patience. Fortunately shipping from China seems to be extremely fast right now... about 9 days!

[photo_van]

Why not use a regular 168 type led plug in bulb? Inquiring minds want to know!

[astroturf]

Why not use a regular 168 type led plug in bulb? Inquiring minds want to know!

X2

[MountainManJoe]

Good question. What would you suggest? Got any links?

[photo_van]

Good question. What would you suggest? Got any links?

Not specifically, that's why I'm watching you! When I googled 168 LED bulb I found about a million different options!

I thought I bookmarked the page, but someone on here somewhere posted a great link. The company actually had a search engine for the make and model vehicle and then select LED bulbs for replacements. It had astro dome and reading lamp replacements, as well as back-up lights etc. It was in one of our fairly recent discussions.....

[photo_van]

Here it is superbrightleds.com They also list a lot of other 168 bulbs in many different light temperatures They are fairly expensive, but I only need two reading lamps.

[MountainManJoe]

Do you mean like these?



They are not nearly as bright as the OEM incandescent bulbs. I want something that is at least as bright, if not more.

[photo_van]

ya, something like that. Brighter is good. The bulbs I've seen are 9300 mcd (whatever that is). I'm not sure how that compares to the incandescent. Here's a 5w bulb http://www.ebay.com/itm/Newcomdigi-T15- ... 109wt_1165

[MountainManJoe]

Candela (cd) is a very deceptive way to indicate brightness, because it's a measurement of luminous intensity, which is power emitted in one particular direction. So of course manufacturers will list the peak value. As we all know, LEDs are very directional. A slight difference in angle could mean a significant drop in intensity. In short, the candela value does not account for total light output.

A better way to measure total brightness is luminous flux. It is the total perceived power of light emitted by a source. You'll notice I said "perceived", because it accounts for the sensitivity of the human eye to certain wavelengths of light. This will be important later on when I post my full write-up, and has to do with the Kruithof curve. The standard unit of luminous flux is alumen (lm).

It's actually measured in a chamber like this!


OK, physics lessons aside, the standard 168 automotive bulbs were roughly 3 candlepower (a now obsolete term actually based on a household candle, which is almost equivalent to a candela). Assuming it radiates uniformly in all directions, we multiply by 4π to get approx. 37 lm.

One thing to keep in mind when buying LEDs: sellers always exaggerate the specifications.

[MountainManJoe]

Here's a 5w bulb http://www.ebay.com/itm/Newcomdigi-T15- ... 109wt_1165

That's a T15 which is a slightly different profile. It's almost twice as wide, and twice as long as a standard 168 bulb. That means you would have to remove the lens and the reflector to make it fit in the existing socket. If you look at the head-on pictures, there is a high power "bead" LED inside. In fact, if it really is 5W ,then it is the exact same LED as the one I featured in my posts. Only this one is packaged in a cylindrical heat sink instead of the disc shaped one on mine.

[photo_van]

168 5 watt
http://www.rockymountainatvmc.com/p/43/ ... tt?ref=gmc

There seems to be a lot of them....

Just sayin'