Universal garage door opener

My daughter has a new 2008 Expedition that has a Universal garage door
opener. Twice they have left home with the garage door closed only to find
it open when they return. They have disabled the universal garage door
opener. Anyone have an idea as to what we should look for to solve the
problem?

Yes, I know this is an Explorer newsgroup, but the Ford Explorer Limited has
a universal garage door opener so I assume it is probably the same one that
is in the Expedition.

Thanks for your help.
Tom

"SF-East Bay'r" > wrote in message
...
> My daughter has a new 2008 Expedition that has a Universal garage
> door opener. Twice they have left home with the garage door closed
> only to find it open when they return. They have disabled the
> universal garage door opener. Anyone have an idea as to what we
> should look for to solve the problem?
>
> Yes, I know this is an Explorer newsgroup, but the Ford Explorer
> Limited has a universal garage door opener so I assume it is
> probably the same one that is in the Expedition.
>
> Thanks for your help.
> Tom

The Homelink system is only universal in the sense that you can
program the "Homelink" transmitter to mimic your standard garage door
transmitter and program your garage door opener to respond to the
signal. The Expedition transmits a particular encoded signal it learns
from your standard opener. You train your garage door opener to
respond to the signal the Expedition transmits (which is the same as
your standard opener). The signal from the Expedition acts just like
your standard opener. I can't think of any reason it would be
responsible for the door opening after the Expedition left the area.
The home link buttons are on the visor. Is it possible that your
daughter is inadvertently pushing the button a second time as she is
driving away when she repositions the visor? Otherwise it seems
unlikely that the Expedition transmitter is doing something different
than the standard transmitter. You might want to contact the Homelink
experts at www.homelink.com or 1-800-355-3515. It might be worth
erasing and reprogramming the button (the instructions are in the
owner's guide
(http://www.motorcraftservice.com/pub...08exdog1e.pdf).

There is an Expedition mailing list. You might ask your question to
that group. See http://mail.xpog.com/mailman/listinfo/expedition

Ed

On Thu, 14 Aug 2008 07:54:33 -0400, "C. E. White"
> wrote:

>
>"SF-East Bay'r" > wrote in message
. ..
>> My daughter has a new 2008 Expedition that has a Universal garage
>> door opener. Twice they have left home with the garage door closed
>> only to find it open when they return. They have disabled the
>> universal garage door opener. Anyone have an idea as to what we
>> should look for to solve the problem?
>>
>> Yes, I know this is an Explorer newsgroup, but the Ford Explorer
>> Limited has a universal garage door opener so I assume it is
>> probably the same one that is in the Expedition.
>>
>> Thanks for your help.
>> Tom
>
>The Homelink system is only universal in the sense that you can
>program the "Homelink" transmitter to mimic your standard garage door
>transmitter and program your garage door opener to respond to the
>signal. The Expedition transmits a particular encoded signal it learns
>from your standard opener. You train your garage door opener to
>respond to the signal the Expedition transmits (which is the same as
>your standard opener). The signal from the Expedition acts just like
>your standard opener. I can't think of any reason it would be
>responsible for the door opening after the Expedition left the area.
>The home link buttons are on the visor. Is it possible that your
>daughter is inadvertently pushing the button a second time as she is
>driving away when she repositions the visor? Otherwise it seems
>unlikely that the Expedition transmitter is doing something different
>than the standard transmitter. You might want to contact the Homelink
>experts at www.homelink.com or 1-800-355-3515. It might be worth
>erasing and reprogramming the button (the instructions are in the
>owner's guide
>(http://www.motorcraftservice.com/pub...08exdog1e.pdf).
>
>There is an Expedition mailing list. You might ask your question to
>that group. See http://mail.xpog.com/mailman/listinfo/expedition
>
>Ed

It's also possible that someone else in your neighborhood has a garage
door opener operating at the same frequency as yours. When they push
the button to operate their door, it also operates yours. Don't know
what you do about that.

"Big_Shoe" > wrote in message
...
> On Thu, 14 Aug 2008 07:54:33 -0400, "C. E. White"
> > wrote:
>
>>
>>"SF-East Bay'r" > wrote in message
.. .
>>> My daughter has a new 2008 Expedition that has a Universal garage
>>> door opener. Twice they have left home with the garage door closed
>>> only to find it open when they return. They have disabled the
>>> universal garage door opener. Anyone have an idea as to what we
>>> should look for to solve the problem?
>>>
>>> Yes, I know this is an Explorer newsgroup, but the Ford Explorer
>>> Limited has a universal garage door opener so I assume it is
>>> probably the same one that is in the Expedition.
>>>
>>> Thanks for your help.
>>> Tom
>>
>>The Homelink system is only universal in the sense that you can
>>program the "Homelink" transmitter to mimic your standard garage
>>door
>>transmitter and program your garage door opener to respond to the
>>signal. The Expedition transmits a particular encoded signal it
>>learns
>>from your standard opener. You train your garage door opener to
>>respond to the signal the Expedition transmits (which is the same as
>>your standard opener). The signal from the Expedition acts just like
>>your standard opener. I can't think of any reason it would be
>>responsible for the door opening after the Expedition left the area.
>>The home link buttons are on the visor. Is it possible that your
>>daughter is inadvertently pushing the button a second time as she is
>>driving away when she repositions the visor? Otherwise it seems
>>unlikely that the Expedition transmitter is doing something
>>different
>>than the standard transmitter. You might want to contact the
>>Homelink
>>experts at www.homelink.com or 1-800-355-3515. It might be worth
>>erasing and reprogramming the button (the instructions are in the
>>owner's guide
>>(http://www.motorcraftservice.com/pub...08exdog1e.pdf).
>>
>>There is an Expedition mailing list. You might ask your question to
>>that group. See http://mail.xpog.com/mailman/listinfo/expedition
>>
>>Ed
>
> It's also possible that someone else in your neighborhood has a
> garage
> door opener operating at the same frequency as yours. When they
> push
> the button to operate their door, it also operates yours. Don't
> know
> what you do about that.

This is not much of a problem with "modern" garage door openers. It is
not just the fequency that matters. They send out a coded signal that
is learned by the opener. Instead of a just a few different
combinations, there are millions of possibilities. The Homelink system
attempts to learn the method used via the programming routine.

From http://en.wikipedia.org/wiki/Garage_door_opener :

"The current garage door opener market uses a frequency spectrum range
between 300-400 MHz and most of the transmitter/receivers rely on
hopping or rolling code technology. This approach prevents
perpetrators from recording a code and replaying it to open a garage
door. Since the signal is supposed to be significantly different from
that of any other garage door remote control, manufacturers claim it
is impossible for someone other than the owner of the remote to open
the garage. When the transmitter sends a code, it generates a new code
using an encoder. The receiver, after receiving a correct code, uses
the same encoder with the same original seed to generate a new code
that it will accept in the future. Because there is a high probability
that someone might accidentally push the open button while not in
range and desynchronize the code, the transmitter and receiver
generate look-a-head codes ahead of time."

See
http://www.johnsoncontrols.co.uk/pub...ndung/FAQ.html
or http://tinyurl.com/5op8ae for more information.

Ed