Can PSM Be Turned Off?

[Feffman]

Hi All:

Newbie here so please forgive any "HUH?" questions. Can the PSM be turned completely off on a 2001-2004 911 Turbo or does it stay on in the "background"?

Thanks.

Feff

[JFP in PA]

PSM equipped cars have an Off siwtch on the dash; however, the system will reactivate automatically under certain circumstances, so "off" is not a true condition.

[BYprodriver]

Pressing the brake pedal reactivates PSM

[Feffman]

Originally Posted by BYprodriver

Pressing the brake pedal reactivates PSM

No way around this for track days?

Feff

[BYprodriver]

Originally Posted by Feffman

No way around this for track days?

Feff

No way designed by Porsche. I assume PSM is standard on all Turbos too.

[jwetering]

Originally Posted by BYprodriver

Pressing the brake pedal reactivates PSM

This is simply not true.

The rumour is that PSM will turn itself back on if you get out of shape, but I have autocrossed my car a number of times and have gotten sideways and the PSM has not turned itself back on under the conditions I have subjected it to.

It definitely will not turn back on if you simply apply the brakes or slide around a bit - what would be the point of the PSM off button then?

Go to the track - turn it off. Let us know if you can get the PSM to turn itself back on. I'll bet you can't.

[JFP in PA]

Originally Posted by jwetering

I'll bet you can't.

You will lose that bet...........

From Porsche literature:

"If you prefer an ever sportier drive, PSM can be switched off. For your safety, however, PSM remains set to intervene if the vehicle is braked and ABS assistance is required. "

[jorian]

"....and ABS assistance is required. " - I guess that is the caveat there. The point of track driving is getting round as fast & efficiently as possible. With PSM off and limiting your slip angle and ABS assistance the computer will allow you to explore limits not possible/prudent on the street. PSM allows a certain slip angle (5-7 degrees)before cutting with the nannies.

At the AutoX, I think that for everything up to and including threshold braking, the PSM will stay off if switched off. If you get into your ABS you have probably over cooked your transition and the car knows it. The cars also have a yaw censor, accelerometer etc which combined with other inputs help keep you from balling the thing up.

Good article here:

http://www.deter.com/porsche/PSM.html

Explains it better than I ever could.

[jwetering]

Originally Posted by JFP in PA

You will lose that bet...........

From Porsche literature:

"If you prefer an ever sportier drive, PSM can be switched off. For your safety, however, PSM remains set to intervene if the vehicle is braked and ABS assistance is required. "

Time for a lesson in basic English my friend.

If the vehicle is braked and ABS assistance is required

does not mean the same thing as

If the vehicle is braked or ABS assistance is required

and if you are hitting your ABS on the track..then you're not doing it right, so I stand by my initial statement.

AX is another story.

and you Jorian....get back to work!

[JFP in PA]

For your "lesson in English" for today, you said, "Go to the track - turn it off. Let us know if you can get the PSM to turn itself back on. I'll bet you can't." Well, I just showed you a way that you can get the PSM to reactivate itself, and provided documentation on the method as well. So it can turn itself back on, which is all that I originally stated, I never said anything about how it happens.

Your bet conjecture had two possible outcomes: “Yes, the PSM can turn itself back on”; or “No, it cannot turn itself back on”. The true outcome of the question at hand is that yes, the PSM system it can turn itself back on.

So, sorry, you still lose the bet, and will now need to take a course in remedial English comprehension as well.......

[jorian]

Evelyn Woodhead.

[jorian]

Straight out of the Owners manual:


When PSM is off, the vehicle is stabilized as
soon as one of the two front wheels enters the
ABS control range.
– When PSM is off and Sport mode is on, the
vehicle is stabilized as soon as both front
wheels enter the ABS control range

[jwetering]

Originally Posted by JFP in PA

So, sorry, you still lose the bet, and will now need to take a course in remedial English comprehension as well.......

It's not even the same thing...

[JFP in PA]

Originally Posted by jwetering

It's not even the same thing...

The only pertinent point in all this is that you lost your proposed bet, and obviously lack the gonads to admit it…..

[jwetering]

Originally Posted by JFP in PA

The only pertinent point in all this is that you lost your proposed bet, and obviously lack the gonads to admit it…..

No...the only pertinent point is that applying the brakes won't turn PSM back on as you initially told the OP. We have learned that invoking the ABS turns the PSM on, and we believe that getting horribly sideways might turn the PSM back on, but applying the brakes will not.

The fact that I assumed you were skilled enough to go to the track and avoid locking up your brakes was indeed a mistake on my part.

You are correct - I'm sure you can get the PSM to turn back on if that is your intent. If you are driving the track as you should however, the PSM shouldn't have to turn itself back on.

The advice for people going to the track is to leave the PSM on. If you find the car intervening - then smooth out your style.

The advice for people who go to the track and turn off their PSM but who find that the car keeps turning it back on is to get another hobby.

[JFP in PA]

Originally Posted by jwetering

No...the only pertinent point is that applying the brakes won't turn PSM back on as you initially told the OP. We have learned that invoking the ABS turns the PSM on, and we believe that getting horribly sideways might turn the PSM back on, but applying the brakes will not.

The fact that I assumed you were skilled enough to go to the track and avoid locking up your brakes was indeed a mistake on my part.

You are correct - I'm sure you can get the PSM to turn back on if that is your intent. If you are driving the track as you should however, the PSM shouldn't have to turn itself back on.

The advice for people going to the track is to leave the PSM on. If you find the car intervening - then smooth out your style.

The advice for people who go to the track and turn off their PSM but who find that the car keeps turning it back on is to get another hobby.

Oh, I see; you lose your bet and now want to set totally fallacious boundaries to alter that fact.

My original statement was: “PSM equipped cars have an Off switch on the dash; however, the system will reactivate automatically under certain circumstances, so "off" is not a true condition.” You will note, and I hope this time understand, I never said anything about stepping on the brakes, nor did I make any statement about forcing the car to activate the ABS system (The braking reference was quote from Porsche literature). The only thing I stated was that “the system will reactivate automatically under certain circumstances”, which was then, and still is correct.

Again, I quote your original statement in response: “Go to the track - turn it off. Let us know if you can get the PSM to turn itself back on. I'll bet you can't.” But as it turns out, you can.....

Sorry, but you still lose.

My advice to you would be to read more carefully before starting a senseless argument, and be careful who you offer driving advice to until you know their track history…….

[jwetering]

Originally Posted by BYprodriver

Pressing the brake pedal reactivates PSM

I formally and fully apologize to JFP in PA. He never said that pressing the brake will turn the PSM back on.

Sorry JFP. I am working on some projects at my desk at work and didn't take the time to check my facts. Nothing you said was incorrect. Of course it's possible to get the PSM to turn back on at the track...but I'll stand by my argument that if you are driving half decently, it shouldn't.

[JFP in PA]

An apology is not necessary, but acknowledged and accepted.