Grade logic "map"

Apparently grade logic downshifting occurs when certain combinations of
braking, rpm and vacuum occur. Can anyone tell me what these combos are
for a 2000 Ody?
Dick

why?

Richard Lane wrote:
> Apparently grade logic downshifting occurs when certain combinations of
> braking, rpm and vacuum occur. Can anyone tell me what these combos are
> for a 2000 Ody?
> Dick

jim beam wrote:
> why?
>
> Richard Lane wrote:
>
>> Apparently grade logic downshifting occurs when certain combinations
>> of braking, rpm and vacuum occur. Can anyone tell me what these combos
>> are for a 2000 Ody?
>> Dick
>
>
Why? Principally in order to know how many times to apply the brales to
induce a downshift but also (being a retired EE) intellectual curiosity.
Dick

doubt i can tell you anything if you're an e.e. it's basically a mapped
system that compares input from the sensors you say with its map.
[although i don't think it measures vacuum directly but minute changes
in angular velocity of the flywheel]. the map, as you probably know, is
not alterable unless you re-chip. it does however retain some
statistical information on driver habits to "learn" to a small degree.
for hills, my 2000 civic would labor in top gear [economy mode] until i
manually dropped it to 3rd. after a few times of manual dropping, it
now does it on its own and keeps it there until it's truly ready to
change up again. quite intelligent really.

i've never done the same for engine braking but in my experience the
standard mapping is quite adequate. it holds it in a lower gear if the
rpms are increasing without throttle so just one moderate brake
application should be sufficient.


Richard Lane wrote:
> jim beam wrote:
>
>> why?
>>
>> Richard Lane wrote:
>>
>>> Apparently grade logic downshifting occurs when certain combinations
>>> of braking, rpm and vacuum occur. Can anyone tell me what these
>>> combos are for a 2000 Ody?
>>> Dick
>>
>>
>>
> Why? Principally in order to know how many times to apply the brales to
> induce a downshift but also (being a retired EE) intellectual curiosity.
> Dick

On Thu, 04 Nov 2004 20:42:35 -0800, jim beam >
wrote:

>doubt i can tell you anything if you're an e.e. it's basically a mapped
>system that compares input from the sensors you say with its map.
>[although i don't think it measures vacuum directly but minute changes
>in angular velocity of the flywheel]. the map, as you probably know, is
>not alterable unless you re-chip. it does however retain some
>statistical information on driver habits to "learn" to a small degree.
>for hills, my 2000 civic would labor in top gear [economy mode] until i
>manually dropped it to 3rd. after a few times of manual dropping, it
>now does it on its own and keeps it there until it's truly ready to
>change up again. quite intelligent really.
>
>i've never done the same for engine braking but in my experience the
>standard mapping is quite adequate. it holds it in a lower gear if the
>rpms are increasing without throttle so just one moderate brake
>application should be sufficient.

Gee, nice explanation of a subject that's new to us non-automotive
types. On what years and models of Hondas is this feature generally
found?
Ron

jim beam wrote:
> doubt i can tell you anything if you're an e.e. it's basically a mapped
> system that compares input from the sensors you say with its map.
> [although i don't think it measures vacuum directly but minute changes
> in angular velocity of the flywheel]. the map, as you probably know, is
> not alterable unless you re-chip. it does however retain some
> statistical information on driver habits to "learn" to a small degree.
> for hills, my 2000 civic would labor in top gear [economy mode] until i
> manually dropped it to 3rd. after a few times of manual dropping, it
> now does it on its own and keeps it there until it's truly ready to
> change up again. quite intelligent really.
>
> i've never done the same for engine braking but in my experience the
> standard mapping is quite adequate. it holds it in a lower gear if the
> rpms are increasing without throttle so just one moderate brake
> application should be sufficient.
>
>
> Richard Lane wrote:
>
>> jim beam wrote:
>>
>>> why?
>>>
>>> Richard Lane wrote:
>>>
>>>> Apparently grade logic downshifting occurs when certain combinations
>>>> of braking, rpm and vacuum occur. Can anyone tell me what these
>>>> combos are for a 2000 Ody?
>>>> Dick
>>>
>>>
>>>
>>>
>> Why? Principally in order to know how many times to apply the brales
>> to induce a downshift but also (being a retired EE) intellectual
>> curiosity.
>> Dick
>
>
Thanks Jim, I didn't know the system learned your shifting habits.
Dick

"Richard Lane" > wrote in message ...

> Apparently grade logic downshifting occurs when certain combinations of
> braking, rpm and vacuum occur. Can anyone tell me what these combos are
> for a 2000 Ody?
> Dick

Grade Logic System monitors throttle position, vehicle speed,
acceleration and deceleration. Based on this information, the system
can determine if the vehicle is on an incline and adjusts the shift
schedule for improved climbing power or downhill engine braking. It
provide downshifts from fifth to fourth or from fourth to third as
required on downhill grades, making effective use of engine braking
to control the vehicle's speed.

Off subject: My digital sewing machine uses Grade Logic System
to monitor throttle position and motor speed. Based on this infor-
mation, the system can determine if the sewing machine is running
over thin or heavy materials and adjusts the current output to the
motor. The result is a steady pedal position at any grade of material.

Milleron wrote:
> On Thu, 04 Nov 2004 20:42:35 -0800, jim beam >
> wrote:
>
>
>>doubt i can tell you anything if you're an e.e. it's basically a mapped
>>system that compares input from the sensors you say with its map.
>>[although i don't think it measures vacuum directly but minute changes
>>in angular velocity of the flywheel]. the map, as you probably know, is
>>not alterable unless you re-chip. it does however retain some
>>statistical information on driver habits to "learn" to a small degree.
>>for hills, my 2000 civic would labor in top gear [economy mode] until i
>>manually dropped it to 3rd. after a few times of manual dropping, it
>>now does it on its own and keeps it there until it's truly ready to
>>change up again. quite intelligent really.
>>
>>i've never done the same for engine braking but in my experience the
>>standard mapping is quite adequate. it holds it in a lower gear if the
>>rpms are increasing without throttle so just one moderate brake
>>application should be sufficient.
>
>
> Gee, nice explanation of a subject that's new to us non-automotive
> types. On what years and models of Hondas is this feature generally
> found?
> Ron

i think the "learned" bit is '99 on. transmissions have had some degree
of electronic control for at least 10 years prior to that, but retaining
driver input data and modifying shift patterns accordingly is relatively
new, at least it is for honda.

Richard Lane > wrote:

> >> Why? Principally in order to know how many times to apply the brales
> >> to induce a downshift but also (being a retired EE) intellectual
> >> curiosity.
> >> Dick
> >
> >
> Thanks Jim, I didn't know the system learned your shifting habits.
> Dick

Learning the shifting habits of the driver on an automatic? :-)