I decided to replace the burned-out bulb in the third brake light on the mighty Aerostar this afternoon. When I tried to take out the dead bulb, the plastic fingers that hold the bulb tight to the contacts both snapped off.

So it was time for something better - an upgrade to LED bulbs. It was a lot easier than I would have expected.

I bought a couple of APC red LED "bulbs" to replace an 1156 bulb (APC part number 504056B).

The third brake light assembly has two parts - the lens/"reflector" part and the bulb holder part which plugs into the wiring harness. I did not re-use the bulb holder.

There are two "windows" in the reflector portion of the lens - one under each bulb. I shaved about 1/16" of plastic off each side of each window to let the bulb slip through. A 5/16" slice of 5/8" heater hose perfectly fit over the base of the bulb and held it snugly in the cavity in the reflector. I cut a small bevel on the edge of the hose to make it easier to angle into the cavity.

With the bulbs in the reflector, I soldered a wire across the center terminal on the bulbs (positive), and soldered wires down both sides of the shells - one for the electrical connection (negative) and & the other to help secure the bulbs in the reflector. I covered the soldered joints and the entire exposed bulb bases in hot-melt glue both to insulate them and also to keep them held tight.

The bulb holder part of the original assembly also forms the plug that connects to the wiring harness. The holder has metallized plastic rails to conduct electricity to the bulbs, and the pins in the plug are also metallized plastic, so they cannot be reused. I used a trailer harness plug and socket to replace the original. I could have soldered it directly to the hatch wiring harness, but I wanted to be able to unplug it if necessary. The green wire in the hatch harness is positive and the black is negative.

The design of the lens assembly keeps the LED lights aimed horizontal, so the LEDs are aimed directly at a following vehicle. They are about twice as bright as the main brake lights, and since they are LEDs, they are "instant on" - faster than incandescent bulbs.

My total time involvement for this project was about two hours, including the parts store run to buy the bulbs and gathering and putting away the tools. I did not take any photos as I went along, but I will take some of the finished works on request.

Cheers,
Eric

 

Sounds like an interesting project. May do it myself.

 

Nice mod. Did you find the LEDs' at an auto supply store?

 

I bought the bulbs at my local Canadian Tire Store. I realize you don't have them in the US, but I would think you could find them at a typical national parts chain like Auto Zone.

Cheers,
Eric

 

Eric, I have noticed the red LED's are good, but darker when covered with a red lense. If you have a clear lense, then the red LEDs work fine. Using a white LED bulb is the way to go, if using the stock red lense cover. That said, LED lights are the way to go. Even in bright afternoon daylight, LEDs look bright, and you can instantly tell that the lights are on. No comparison to incandesents, LEDs are superior. Does anyone know where to purchase a WHITE LED #1157 bulb resonably? I see red LED 1157s for around $7.00 a bulb, and the white LED #1157s jump to $25.00+ per bulb! I mean, I'd go for say $19.99 for a pair of white #1157 bulbs (they last longer and burn cooler too) but at almost $50.00 for a pair of white LEDs seem a tad high. Comments? I've seen white LED #1156 bulbs (turnsignals and back-up lights) for $9.99 each. Maybe some of you know of a good company to order these LEDs from the internet? Thank You.

 

They sell the LEDs in bulb form just like the original bulb?

So if the socket wasn't broken you could have just plugged them in place of the old bulbs?

Another thing I know since I work on electronics often is it is VERY important to know what the LEDs max current rating is if its over the current being supplied by the brake light wires you have to solder in a resistor before the + line enters the first led about $1 for 5 of them at your local electronics store to downstep the current or your LED will glow orange for a few seconds and blow itself out.

This sounds pretty cool I'm getting sick of replacing that light too I'm gonna go for it .

 

Ed/Krank: I have seen the opposite recommendation for LED light and lens covers i.e. keep the LED color and the lens color the same. These recommendations are mostly for industrial equipment pushbuttons, which admittedly are typically in relatively dim surroundings. The concern is that white LEDS are so bright & pin-point that they will shine nearly white through a colored lens.

For an automotive web source of info (don't know if you can buy from them) for LEDs, try www.truck-lite.com These are the folks who actually made the third brake light for the Aerostar - their logo is on the lens.

For general info on LED "light bulbs" check out www.ledtronics.com These folks make the LED traffic lights, LED automotive "light bulb" replacements, LED "light bulbs" for houses (both 110 VAC and 12 VDC equivalents for home solar/battery lighting). A lot of what I learend about LED "light bulbs" I read there.

I put the quotes around "light bulbs" because they are really circuit-board LEDs grouped and packaged to mimic traditional bulbs. There is a resistor and diode built into the package for current/voltage limiting reasons. The ones I used have the traditional bayonet base that an 1156 has. The incandescent bulbs originally used the in the light have a glass wedge base (like older-style side marker and dash lights). I'm sure there are wedge-base LEDs available, but I had four reasons for using the 1156 replacements:
1) I know an 1156 is sufficiently bright for a brake light. A wedge base LED intended for a side marker would not.
2) The wedge base socket broke when I removed the glass bulb, so I was looking for something different anyway.
3) LEDs are fairly directional in their intensity. Due to the configuration of the third brake light, I knew the LEDs on the 1156 would shine in the right direction. Some of the wedge base LED assemblies are designed to throw light sideways, which in the case of the Aerostar would be straight up or straight down - useless.
4) The store I went to only had 1156s and 1157s. I worked with what I had available.

For what it's worth, red LEDs are the cheapest to make (they were also the very first color available). "White" LEDs are actually a very pale blue, but are so bright that they appear white. They are the most expensive color to make, hence the most expensive color to buy.

Ed: Keep the LED directionality in mind before you shell out for the 1157s. If the LEDs end up pointing directly to the rear of the vehicle, it is a good application. If they end up pointing sideways they will not show where they are needed at all. I think the main brake light bulbs in the Aerostar point off at an angle, so the LED assembly would show very dim to the rear of the van. I'll have to double-check the direction of the bulbs the next time I replace one. I seem to replace a brake light bulb every few months, so I would dearly love to use LED 1157s

An 1157 will always be more expensive than an 1156 because the 1157 must shine with two different intensities. One way to get two intensities is to only turn some of the LEDs in the assembly on for the low intensity and all of them on for the high intensity. The second way is to add a second resistor to the circuit for the low intensity, but light all the LEDs. The intensity decreases as the current flow through the LED decreases, so they don't shine as bright. Either way requires more circuitry and therefore extra cost. An incandescent 1157 may not be more expensive than an incandescent 1156, but the manufacturing cost differences for such mass produced items is negligible compared to the costs of packaging and shipping. And let's face it, LED replacement "bulbs" will always be something of a novelty item. As the car manufacturers adopt them the LEDs are assembled directly into the lens assembly and are not considered a replacement item. As LEDs are adopted for use in residential and commercial lighting they will also be directly assembled for many reasons - cost, their directionality and the design flexibility.

Sorry for the long post - I've been a big fan of LED lighting for a while & this discussion got me started. I'll be quiet now...

Cheers,
Eric

 

Eric, thanks very much for your EXCELLENT response, one in which I have printed out, so I can re-read several times when I am away from the computer. You make some very valid points, Eric, that quite honestly I was not sure of. All I know is I have recently become interested in the LED lighting, as it's the future of lighting, not only with cars and trucks, but signs, etc. Even LED redlights, you can see them from miles away! Even the NHRA Drag Racing is using LEDs in the "Christmas Trees" now, on the starting line.
Eric, ironically, you mentioned the company LedTronics. I have heard of them before, and in today's mail, I received their big, information packed catalog. I had ordered it about two weeks ago from their website, and am I ever glad I did. The reason is my work is in the process for installing LED lighting on their truck trailer fleet, including clearence and running lights. I discovered LedTronics on the internet, (based in Torrance, CA) and they are a highly reputable company. If you don't have their catalog, Eric, order a copy from their website. It will arrive in the mail, HUGE, and has so much LED information, you will not be able to comprehend it all in one sitting! LedTronics is the authority. More later...I'll check back here tomorrow and over the weekend. Thanks again Eric, for the information on LEDs! ED

 

Ed,

If you're going to replace the brake lights with LEDs, you should stick with the red color. As Eric mentioned, they are the cheapest, but that's not the most important reason. The red LED's are the most efficient at converting electricity to photons, and they are available in the highest output of any colors. But the most important reason not to use white LEDs behind a red lens is this: White LEDs look white because they start out with a blue LED, shine it through yellow phosphor, which glows yellow, and the mix of the two colors are perceived by your eyes as white, like from a flourescent tube. They often do not have the right mix, so they tend to appear bluish. Also, blue LEDs are the least efficient at converting electricity into visible light. All the energy that is not emitted as visible light is emitted as wated heat. But the real problem is, they have very little red component in their emitted spectra, so you will be wasting most of the visible light that it generates, like a standard white light bulb.

All LEDs are like transistors; a tiny piece of semiconductor but it is made to glow. Most manufacturers use a magnifier lens or a light collector in front of the emitter to control dispersion. For your stop lights, you should get LEDs with at least 45 degree dispersion angle.

It is important to make sure they are not overpowered, or they will become one time noise emitting diodes. Most LEDs run at 20 to 30 milliamps at around 2 to 3 volts. You can string a bunch of them together to build up their voltage requirement to 12 volts, and put a resistor in series to compensate for the rest of the voltage difference and limit current. Assuming the charging system puts out 14 volts, you need to drop 2 volts, and let no more than 25 milliamps through, then you need an 80 ohm resistor for each string.

See if LEDTronics carry any of the small LED panels made by Lumex. They have 10 to 24 small LEDs mounted in small clusters about the size of a 1156 bulb, and are very bright. They sell for a few dollars each, and I think are just about perfect for bulb replacements. If LEDtronics doesn't carry them, Digikey does.

My brother replaced the bulbs in the turn signals on his car with large 1 watt LEDs from Lumileds. They're called Luxeon Stars, and are very bright. Unfortunately, like high powered transistors, they will burn themselves out if not properly heat sunk and current limited. He built a circuit that runs them at about half power for the marker lights, and switches them to full power only with the blinkers for turning or emergency flashing. It was a necessity for him because the bulbs burned out pretty often, and required pretty major disassembly of some body panels to get to them.

 

XLT4WD90, Thank You. Your post made perfect sense. I am still learning about the LED technology, you and Eric know your stuff. I appreciate it. Yesterday, I was behind a guy towing a new or almost new Malibu ski boat. He had LED trailer lights, and when the brake lights came on the trailer, they not only looked cool, but the brightness and immediate illumination was amazing. Thanks again. Ed...

 

Keep it coming Eric! You have my undivided attention. I'm sick and tired of changing the rear bulbs too. I think the vibrations back there are too much for these bulbs to last.

 

I had a chance to see the brake lights in action for the first time a couple of nights ago. The LEDs are decently bright and noticeably faster than the main brake lights. Very cool.

I took a look through the Digi-Key catalog & noticed they sell 1156 and 1157 LED bulbs ("Sunbrite" brand) for really good prices. I will post an update when I remember to bring the catalog home for a night.

I took some quick measurements & I think the LED elements out of a 6" Oval truck/trailer stop-turn-tail light could be fitted into the Aerostar's tail/brake lens. It's a little more surgery than I'm willing to attempt right now, though.

Cheers,
Eric

 

I just put halogen lamps in the Brake, Back-up, and turn signals. Cheaper and brighter then LED.

 

Muffinman:

My problem with these is not that they are not bright enough. It's just that they get burned out at the most inconvenient moments, e.g. at night on a long trip with a nagging wife and 4 rowdy kids Anyway, do these halogen lamps suck more current than the regular lamps? If so, you might have to be careful.

Regards

 

I think the rated watt was 15, Which is 5 watts more then a regular one.