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  #16  
Old 05-17-2004, 06:00 PM
oab_au oab_au is offline
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Quote:
Originally posted by Sonar
UberRoo, -please clearify that cabling/switch you've found, and how do you know what it does?

Interesting



/Sonny
I think all models are fitted with this unit.









Its called a gear lever

Harvey.
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  #17  
Old 05-17-2004, 06:23 PM
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Quote:
Originally posted by deruvian
Looks like we may have to try Harvey's method. Have you checked it out Harvey?
No mate I am happy with the stock model I just like to help anyone that wants to try things, to keep them on the right track.

Yes there is no reasion why it won't. The temp sensor is a special resistor that reduces its resistance as it gets hotter.

At 20 degs C/68F it has a resistance of about 2.5Kohms
At 80 degs C/176F it goes down to about 330 ohms. Which brings the ATF light on ,and changes the shift points to move more ATF through the cooler.

Running a wire from one side of the sensor, to a switch, to a 220/330ohm resistor, then back to the other side of the sensor wire, will drop the resistance to a level low enought to do it. If the resistance is too low, the TCU may post a code.

Harvey.
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  #18  
Old 05-17-2004, 06:33 PM
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Quote:
Originally posted by Sonar
My thoughts Harvey

So you don't see any sideeffects on this?

My first though was to put a potentiometer in parallell of the sensor, so I could adjust it to not trig the faultcode of a broken sensor, but maybe it's unnecessary.


/Sonny
Yes you could do that, to find the best resistance to use, as it is in parallel with the varying sensor resistance.

Can't see any side effects to it,other than the ATF light will be on, in this mode, so it can't signal a high ATF temp problem.

Harvey.
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  #19  
Old 05-17-2004, 07:19 PM
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Re: Power Mode

Thanks alltrac! I never knew that... I do see that AT oil temp light at start up. Cool!

-Chike
Quote:
Originally posted by alltrac
OBDll cars don't have a power mode light. They still go into power mode just no light to tell you. OBDll cars do have a AT oil temp light. You will see it on start up for a couple of seconds and then it goes out, unless you have a trouble code. If the fluid does get to hot while driving the TCU goes into power mode. Subaru should have called it shift mode, shift smart, shift logic or some other BS because it doesn't make powa.
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  #20  
Old 05-17-2004, 07:39 PM
deruvian
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Quote:
Originally posted by oab_au


No mate I am happy with the stock model I just like to help anyone that wants to try things, to keep them on the right track.

Yes there is no reasion why it won't. The temp sensor is a special resistor that reduces its resistance as it gets hotter.

At 20 degs C/68F it has a resistance of about 2.5Kohms
At 80 degs C/176F it goes down to about 330 ohms. Which brings the ATF light on ,and changes the shift points to move more ATF through the cooler.

Running a wire from one side of the sensor, to a switch, to a 220/330ohm resistor, then back to the other side of the sensor wire, will drop the resistance to a level low enought to do it. If the resistance is too low, the TCU may post a code.

Harvey.
I wonder if this would work on the FWD models, as they have no ATF temp warning light.

Does anyone know how the power mode switch works in the Euro model SVXen? Does anyone have a wiring diagram from one of these "switch-equipped" models? I suppose all you'd really need is a quality wiring diagram to tell you where to start.
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  #21  
Old 05-18-2004, 04:38 AM
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I'm gonna do this when I'm back home this weekend

Maybe I rewire the original "ECON" function to some other switch (hidden), and wire the new "POWER" function to "ECON" switch, nice to have it handy in case of "emergency"

Maybe I relabel it to "DECFON MODE"

..and UberRoo, got me there ...didn't read and understand the post in full


/Sonny
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Last edited by Sonar; 05-18-2004 at 04:40 AM.
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  #22  
Old 05-18-2004, 04:44 AM
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deruvian, the "Euro" model does not have the "Power" switch, that's why I'm trying to implement one




/Sonny
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  #23  
Old 05-18-2004, 04:46 AM
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I think only the JDM model has one, maybe we ask Joe (svxistentialist) if he has a wiring diagram, he have a JDM (I think?)




/Sonny
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  #24  
Old 05-18-2004, 03:50 PM
deruvian
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Quote:
Originally posted by Sonar
deruvian, the "Euro" model does not have the "Power" switch, that's why I'm trying to implement one
That's right... They have the Econ. switch instead. Woops.
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  #25  
Old 05-19-2004, 03:51 AM
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A couple of things you may consider, (or already have,) is that (1.) when the TCU is in power mode it tends to hunt for gears, and (2.) the "power mode" which is caused by hot ATF may not be the same power mode that is caused by rapid application of throttle.

In normal operation, there's a margin between how much throttle is needed to get a downshift and how little throttle is needed to get an upshift. This 'null zone' keeps the transmission from switching gears at the slightest change of throttle. In power mode, the 'null zone' becomes very narrow and almost undriveable.

The next time you're at freeway speeds, romp on it and get the TCU into power mode, then abruptly let off the gas for just a second - maybe a couple of times. Notice how quickly it changes gears? It's like an annoying hiccup. If you do this a few times, you'll find the transition point (where it shifts) on your throttle pedal. If you hold the pedal at that point and just wiggle your foot slightly, it'll jump back and forth between gears like crazy (as long as you're in power mode.)

You can do this at low speeds too, but it's a bit harder to do as the TCU goes back into normal mode rather quickly. Power mode works very well if you just want to accelerate, but the TCU gets very confused if you want it to do anything else.

I think you'll find it very undriveable. Don't get me wrong. Experiment with it. It'll probably be a pain to drive, but a lot of fun while you toy with it. If it works, you'll be a hero to many.
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  #26  
Old 05-19-2004, 07:55 AM
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Quote:
Originally posted by UberRoo
A couple of things you may consider, (or already have,) is that (1.) when the TCU is in power mode it tends to hunt for gears, and (2.) the "power mode" which is caused by hot ATF may not be the same power mode that is caused by rapid application of throttle.

In normal operation, there's a margin between how much throttle is needed to get a downshift and how little throttle is needed to get an upshift. This 'null zone' keeps the transmission from switching gears at the slightest change of throttle. In power mode, the 'null zone' becomes very narrow and almost undriveable.

The next time you're at freeway speeds, romp on it and get the TCU into power mode, then abruptly let off the gas for just a second - maybe a couple of times. Notice how quickly it changes gears? It's like an annoying hiccup. If you do this a few times, you'll find the transition point (where it shifts) on your throttle pedal. If you hold the pedal at that point and just wiggle your foot slightly, it'll jump back and forth between gears like crazy (as long as you're in power mode.)

You can do this at low speeds too, but it's a bit harder to do as the TCU goes back into normal mode rather quickly. Power mode works very well if you just want to accelerate, but the TCU gets very confused if you want it to do anything else.

I think you'll find it very undriveable. Don't get me wrong. Experiment with it. It'll probably be a pain to drive, but a lot of fun while you toy with it. If it works, you'll be a hero to many.
No offense, but I have to disagree. I drive a JDM SVX (factory fitted with a power mode switch). It is not almost undriveable and it doesn't jump back and forth between gears.
I regularly drive with the power mode switch on because it makes the car feel a little more responsive - it tends to be in the right gear at the right time, rather than being one gear too high.

Phil.
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  #27  
Old 05-19-2004, 11:46 PM
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b3lha,

I would not disbelieve, but would be surprised if your Power Mode button causes the same performance that the automatically activated power mode causes in U.S. cars. I know that the power mode does cause some undesirable behavior in my car, but because the mode is used only in great moderation, it's of relatively little consequence.

How does your Power Mode button work? At what speeds does it downshift when coasting? How is it wired? It would be very interesting to know if the behavior of your manual activation is the same as our automatic activation. It would also be interesting to know where the wires go. Perhaps you share the exact same TCU, and the only thing missing from ours is the wiring and switch. That would be very cool.

Personally, I like driving the torque-monster. I love being able to climb steep hills in high gear with the torque converter locked up. ...but your right, it's not sporty, and I understand why the shift points would not suit your mood if you're feeling frisky.
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  #28  
Old 05-20-2004, 12:22 AM
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JDM models

JDM models have the same 'automatic' activation of 'Power Mode' as US models. Plus 'manual' activation via the console switch.
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  #29  
Old 05-20-2004, 07:42 AM
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Quote:
Originally posted by UberRoo
How does your Power Mode button work? At what speeds does it downshift when coasting? How is it wired? It would be very interesting to know if the behavior of your manual activation is the same as our automatic activation. It would also be interesting to know where the wires go. Perhaps you share the exact same TCU, and the only thing missing from ours is the wiring and switch. That would be very cool.
I think the non-US cars have a different TCU because of the VTD transmission (as opposed to the US clutch type). I've never traced the wires, and I don't have a diagram, but I assume the switch just grounds a pin of the TCU.
I find the downshift points difficult to determine, but at WOT, it seems to upshift at the 6500 redline: to 2nd at just over 40mph, 3rd at about 85 and 4th at about 115-120 (although I rarely go that fast).

Phil.
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  #30  
Old 05-20-2004, 08:45 AM
deruvian
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Quote:
Originally posted by b3lha

I think the non-US cars have a different TCU because of the VTD transmission (as opposed to the US clutch type).
Damn... Good point. I was just starting to get hopeful.

Does anyone on the boards have a JDM ECU or TCU wiring diagram?
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