Since I don't use the garage for a car, I don't need to open it very
often. But when I do, I have to push the button on the remote anywhere
up to a dozen times before the door opens. Once it's open, it will close
and open first time every time. Until I close the door and leave it
alone for a few days. Then it's back to the same old tricks.


I've checked the battery, resoldered everything that looked even
slightly suspect (along with some that looked fine, just because) and
replaced the PCB-located switch. I also did a reset on the codes and
started over (it's a "learning" device, not the kind with a bunch of
little switches).

Sadly, I do not have any RF test gear to see if the remote is actually
transmitting.

Other than via the overhead door, access to the garage is through a
rental unit, so being inside when I try the thing "fresh" is not an
option.

Suggestions?

Isaac

On 19/11/15 15:44, isw wrote:
Since I don't use the garage for a car, I don't need to open it very
often. But when I do, I have to push the button on the remote anywhere
up to a dozen times before the door opens. Once it's open, it will close
and open first time every time. Until I close the door and leave it
alone for a few days. Then it's back to the same old tricks.


I've checked the battery, resoldered everything that looked even
slightly suspect (along with some that looked fine, just because) and
replaced the PCB-located switch. I also did a reset on the codes and
started over (it's a "learning" device, not the kind with a bunch of
little switches).

Sadly, I do not have any RF test gear to see if the remote is actually
transmitting.

Other than via the overhead door, access to the garage is through a
rental unit, so being inside when I try the thing "fresh" is not an
option.

Most systems use a rolling code that moves through a predetermined
pseudo-random sequence, where the sequence is determined by the secret
key. The receiver remembers recent codes used, and can detect whether
the code just received is correct in any sequence for the known remotes.
After it has received the neighbour's remotes or other in-band signals
with incorrect codes, it takes more repetitions of correct code
sequences before it's willing to unlock.

https://en.wikipedia.org/wiki/Rolling_code

Clifford Heath.

On Wed, 18 Nov 2015 20:44:10 -0800, isw wrote:

Since I don't use the garage for a car, I don't need to open it very
often. But when I do, I have to push the button on the remote anywhere
up to a dozen times before the door opens.

I barely understood your post or the reply, but what happens if you
push the remote once (or maybe twice) and wait the same length of time
that it would take you to push the button those dozen times?

IOW, is it responding to the first push but taking forever to do it,
or to the last push?

Once it's open, it will close
and open first time every time. Until I close the door and leave it
alone for a few days. Then it's back to the same old tricks.

On 19/11/2015 05:14, Clifford Heath wrote:
On 19/11/15 15:44, isw wrote:
Since I don't use the garage for a car, I don't need to open it very
often. But when I do, I have to push the button on the remote anywhere
up to a dozen times before the door opens. Once it's open, it will close
and open first time every time. Until I close the door and leave it
alone for a few days. Then it's back to the same old tricks.


I've checked the battery, resoldered everything that looked even
slightly suspect (along with some that looked fine, just because) and
replaced the PCB-located switch. I also did a reset on the codes and
started over (it's a "learning" device, not the kind with a bunch of
little switches).

Sadly, I do not have any RF test gear to see if the remote is actually
transmitting.

Other than via the overhead door, access to the garage is through a
rental unit, so being inside when I try the thing "fresh" is not an
option.

Most systems use a rolling code that moves through a predetermined
pseudo-random sequence, where the sequence is determined by the secret
key. The receiver remembers recent codes used, and can detect whether
the code just received is correct in any sequence for the known remotes.
After it has received the neighbour's remotes or other in-band signals
with incorrect codes, it takes more repetitions of correct code
sequences before it's willing to unlock.

https://en.wikipedia.org/wiki/Rolling_code

Clifford Heath.

I never realised it was that straightforward. Never having researched
it, I'd thought is was some impenetrable immensly complex , uC software,
pseudo-random number sequencing and varying the seeds for different
makes and individual matched send/rec combinations.

Since I don't use the garage for a car, I don't need to open it very
often. But when I do, I have to push the button on the remote anywhere
up to a dozen times before the door opens. Once it's open, it will close
and open first time every time. Until I close the door and leave it
alone for a few days. Then it's back to the same old tricks.


I've checked the battery, resoldered everything that looked even
slightly suspect (along with some that looked fine, just because) and
replaced the PCB-located switch. I also did a reset on the codes and
started over (it's a "learning" device, not the kind with a bunch of
little switches).

Sadly, I do not have any RF test gear to see if the remote is actually
transmitting.

Other than via the overhead door, access to the garage is through a
rental unit, so being inside when I try the thing "fresh" is not an
option.

Suggestions?

Remote systems which use a "rolling code" can fall out of
synchronization (the receiver expects a different code than the remote
is sending) for any of a number of reasons:

- You accidentally push the button on the remote while "out of range"
of the receiver. This can happen pretty easily if the remote is in
your pocket... sort of like "butt-dialing" a phone.

- There's another door opener of the same brand and type located
close to your home, and your receiver "hears" transmissions meant
for your neighbor's remote.

In both of these cases, when you try to access the door, the "rolling
code" part of the transmission it makes is in a different part of the
sequence than the receiver expects to hear.

The receiver will typically treat this as either a brute-force attempt
to open the door, or a "replay attack" (somebody recorded your
transmission and is playing it back).

The systems often have a "resynchronization" feature, in which
transmitting a long series of correct codes in the proper sequence
will "convince" the receiver that the remote is the right one and is
properly paired. The receiver then resets its sequence to match that
of the remote.

The "up to a dozen times" sounds reasonable for a resynchronization.

Check the manual for your door opener - if it has this sort of
rolling-code/resynchronization architecture the manual will probably
say so.

If that's your problem... you'll probably have to live with it... but
maybe keep the remote control in a place where its button isn't likely
to be pushed by accident.

In article , says...

On 19/11/15 15:44, isw wrote:
Since I don't use the garage for a car, I don't need to open it very
often. But when I do, I have to push the button on the remote anywhere
up to a dozen times before the door opens. Once it's open, it will close
and open first time every time. Until I close the door and leave it
alone for a few days. Then it's back to the same old tricks.


I've checked the battery, resoldered everything that looked even
slightly suspect (along with some that looked fine, just because) and
replaced the PCB-located switch. I also did a reset on the codes and
started over (it's a "learning" device, not the kind with a bunch of
little switches).

Sadly, I do not have any RF test gear to see if the remote is actually
transmitting.

Other than via the overhead door, access to the garage is through a
rental unit, so being inside when I try the thing "fresh" is not an
option.

Most systems use a rolling code that moves through a predetermined
pseudo-random sequence, where the sequence is determined by the secret
key. The receiver remembers recent codes used, and can detect whether
the code just received is correct in any sequence for the known remotes.
After it has received the neighbour's remotes or other in-band signals
with incorrect codes, it takes more repetitions of correct code
sequences before it's willing to unlock.

https://en.wikipedia.org/wiki/Rolling_code

Clifford Heath.

Yup, my Jeep has the same problem.. Sometimes when I am parked in a lot
with many of cars, the hand grab auto unlock will not work, unless I
stand there for a few seconds then it works and it'll work
just fine repeatively.

Jamie

There's a possibility that the remote isn't the issue. The door might
simply be stuck and repeated button pushes finally 'pry' it loose.


On 11/18/2015 8:44 PM, isw wrote:
Since I don't use the garage for a car, I don't need to open it very
often. But when I do, I have to push the button on the remote anywhere
up to a dozen times before the door opens. Once it's open, it will close
and open first time every time. Until I close the door and leave it
alone for a few days. Then it's back to the same old tricks.


I've checked the battery, resoldered everything that looked even
slightly suspect (along with some that looked fine, just because) and
replaced the PCB-located switch. I also did a reset on the codes and
started over (it's a "learning" device, not the kind with a bunch of
little switches).

Sadly, I do not have any RF test gear to see if the remote is actually
transmitting.

Other than via the overhead door, access to the garage is through a
rental unit, so being inside when I try the thing "fresh" is not an
option.

Suggestions?

Isaac