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  #31  
Old 02-04-2007, 05:36 PM
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Originally Posted by svxistentialist
Yeah. A lot. Thank you.

If the 0-5v break is short enough, then the TCU circuitry decides that Power mode is required [because of the sudden-ness of voltage rise] but because the 5V is not maintained, it does not cause kickdown to a lower gear.

That is magic in a way.

You are then saying that the shift map uses rpm and road speed to assign gear changes. But these changes are assigned from the Power mode shift map, not from the Normal map.

The key or trick to it is keeping the 0-5V interval very short, using the 555 switch, that presumably has a variable interval.

Thanks Mike, that seems to solve the conundrum.

Joe
If you use a 555 timer to switch the TPS line to the TCU, between 0V to 5V, it will also cause the line pressure to switch between full and low pressure, through the Dropping resistor circuit.

Harvey.
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  #32  
Old 02-04-2007, 06:03 PM
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Quote:
Originally Posted by oab_au
If you use a 555 timer to switch the TPS line to the TCU, between 0V to 5V, it will also cause the line pressure to switch between full and low pressure, through the Dropping resistor circuit.

Harvey.
Thanks Harvey.

Do you know if the line pressure is able to respond to such an input? I mean one of 250ms or less?

Joe
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  #33  
Old 02-04-2007, 06:47 PM
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Quote:
Originally Posted by oab_au
If you use a 555 timer to switch the TPS line to the TCU, between 0V to 5V, it will also cause the line pressure to switch between full and low pressure, through the Dropping resistor circuit.

Harvey.
As always a definitive statement.

The dropping resistor circuit is in no way involved with any operative control signal. Your lack of understanding in this respect is already well recorded.

In what way will the line pressure be induced to change as a result of very short pulses? This type of signal already exists in respect power mode activation as well as kick down as has been demonstrated through experiments.
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  #34  
Old 02-04-2007, 07:29 PM
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Originally Posted by svxistentialist
Thanks Harvey.

Do you know if the line pressure is able to respond to such an input? I mean one of 250ms or less?

Joe
Don't know Joe, but I am sure it will try.

Harvey.
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  #35  
Old 02-04-2007, 09:50 PM
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Originally Posted by oab_au
Don't know Joe, but I am sure it will try.

Harvey.
Harvey, you keep expounding a theory whereby you contend that the TPS in itself originates a control signal, and this is incorrect.

All signals from the TPS comprise an input to the TCU and it is only after processing that any output results. Line pressure control is dependent on several functions, not simply the input from the TPS.

It is documented fact that the TCU receives two separate types of signal from the TPS, one on the basis of speed of accelerator depression and the other the position of the accelerator. Experimentation now indicates that there could be a third based on a short application of the accelerator i.e. there is probably a time base in respect of first documented signal.

All of this is logically covered within the thread, but evidently has gone over your head.
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