Re-Packaging Homelink Automotive Universal Remote
Garage openers for cars are a pretty simple thing. Stick the thing on
a visor or in an unused ashtray, or leave it in the console, and it's always
handy. Motorcycles make things a little more annoying. Gloved
hands reaching into pockets don't work so well, and garage openers in
pockets don't work out so well either. The buttons get pressed and
batteries wear out, or the cases stab into you or get damaged, and can even
injure you in an accident. Dismounting the bike and using keys is far
from convenient, and who wants to go digging into a tankbag or tailpack for
keys or the opener every time.
Envious of the convenient Homelink transceiver built into the overhead
console of my Honda Accord, I decided to equip my motorcycle with its own
garage opener. The first idea that came to mind was to velcro a spare
remote onto the bike somewhere. The remotes my building uses are
usually leased and if you can buy one, they're more than $100. That's
a bit expensive for something that probably isn't even durable enough for
the vibration and the humidity and temperature swings anyway.
Unfortunately I discovered that due to our system's somewhat
unusual operating frequency - 295MHz - and the recent abuse of the DMCA laws to rid the market of most RF learning remote
controls, only the Homelink
programmable remote control systems would work for me. Problem was, at the
time the Homelink
transceivers were available only as OEM accessories in automobiles. And according to
Johnson Controls, they would never be available in portable applications.
Darned party poopers...
Well, Johnson Controls eventually did wake up and licensed Homelink to
Mito Corporation, who introduced a Homelink motorcycle garage opener at the
2006 International Consumer Electronics Show and got it to the retail market
sometime later that year with sufficiently little fanfare that I didn't come
to know about it until a year after (and two years after this adventure
described here). But congrats to Johnson Controls
and Mito Corp anyway, and hey, it only took y'all a decade! For
a healthy $150 or so you can finally
have a portable battery powered Homelink transceiver of your
own. I still like my solution better...
Lack of retail availability
was no obstacle to me of course. On eBay I located a Homelink
-equipped overhead light console from an auto salvage dealer. A quick
word of advice here, particularly if you have a queer garage system like we
have - choose something from at least the year 2000 or so - not all Homelink
transceivers are equal. If you're patient, you should be able to
snag one of these in good shape for under $50, shipped.
The photograph on the left shows the
transceiver circuit board and the button/LED circuit board connected
together by a ribbon cable, just before being removed from the part of the
console that held it and the two overhead lamps along with sunglass storage
compartment, etc. Getting there is not easy because all the major
plastic pieces are welded together. Just work slowly and use flush
cutters to snip away the welds as you go.
I saved the FCC sticker from the assembly to
use in the transceiver's new case, figured out the power and button wiring, did some
measuring and ordered up a suitable plastic housing. I chose part # 537-400-I-BK from
would work nicely for me since I didn't need room for the original buttons
and LED. It turned out that the inner dimensions of this plastic housing were actually
just a smidgen
too narrow, so I cut shallow slots into the inside walls of the housing and did
some careful filing on the edges of the circuit board. The Homelink transceiver circuit board
now snaps neatly into the slots for a durable,
vibration -resistant assembly.
The photograph on the right shows the
transceiver snapped into place, with just enough room for the various wires
to snake underneath. The 12V power wires are soldered onto the
protruding part of the circuit board, + on the bottom, - on the top, middle
un-used. The wires for the push button and the indicator LED are seen
coming from the opposite side of the circuit board (a wiring guide is shown
here below). Holes were drilled into the case walls for the wires as
necessary, just large enough for the chosen grommets and wires.
Two foam rubber "feet" were adhered to the
inside of the case lid to help secure the board against vibration.
They are set to press lightly against the antenna, which is the long metal
piece on the upper edge of the circuit board. You can see the
impressions in the rubber.
Sharp-eyed readers may notice that the
circuit boards used in the two photographs are slightly different. One
circuit board was damaged due to an electrical gaffe during testing so I had
to purchase another console.
The assembled housing is now hidden safely
inside the motorcycle's fairing, fastened to the machine with 3M Superlock (aka Dual Lock)
for a secure and easy to maintain installation, all
wiring openings sealed with tight rubber grommets and silicone sealant, and the device
is wired to the bike's taillight circuit so that it is only usable when the ignition
is "on" for security.
As far as wiring requirements go, the
transceiver draws over 250mA, but even thin #28 wire is more than enough for
that. I happened to use a heavier gauge wire because it was simpler to
mate to the crimp connectors I have, and it's more durable. Always use
marine -grade power connectors and wire for motorcycle work, and use
professional crimping tools! I recycled part of an old USB cable for
the button and LED wiring. The USB cable is fairly flexible, heavily
jacketed and durable, and the small wire gauge lent itself well to being
soldered to the pads on the circuit board. Remember to provide strain
relief at the grommets! Don't want those tiny wires getting pulled
Always thinking about maintainability and
durability, I used weatherproof quick disconnects in all the wiring for
power, buttons, etc. In case you're wondering about the big focus on
durability, New York City streets and all-weather riding can quickly take
its toll on anything less.
The last challenge was to find a weatherproof
pushbutton with a shallow enough panel depth design to fit the location I
took hours of searching the Internet and scouring the catalogs of major
electronics suppliers such as Digi-Key, Newark and Mouser. I
eventually found a delightful solution in Apem's IP series pushbuttons.
There are plenty of
other weatherproof pushbuttons with broader retail availability if you have a
little more room. This style happens to blend nicely with the bike, as
if the button were OEM equipment.
Homelink systems offer
three programmable buttons but I used only one, at least for now. The
button was placed within easy reach (just under the rearward portion of the
windscreen) and is located in a way that even winter gloved hands could
easily operate the button with a ham-fisted squeeze.
The only tricky part in all of this, really, is
getting the button and LED wiring correct. The table below shows the
wiring pattern for the transceiver circuit board, as if viewing the back of
the board with the power connector on the left and the pads for the
button/LED cable in the lower right corner. In practice the ground
plane is not used. All switches are momentary NO (normally open).
The LED can be any standard ~20ma LED. Take care not to short any of
the pads during soldering. Even without power applied, the transceiver
is "live". You don't necessarily need the LED in normal operation but
it's important during programming.
It's not that big a deal to transplant the
Homelink circuit board as long as you can fish it out without damaging it,
and get the wiring correct. Other tinkerers may choose to keep the
original integrated buttons from the console, which at the cost of some
extra creativity required to design them into their new fixture certainly
makes the electronic aspect easier.
My end result compared to the products offered
by Mito is that my garage opener can't easily be abused
to facilitate the theft of my own vehicles or other vehicles in the garage,
it can't be easily stolen or vandalized, I never have to worry about the
battery or about the unit's weather resistance and durability, and my
installation is not at all obvious.