PSM Turn Off

I want to turn it off !!! On a racing day I would like to turn the PSM off and keep it off for the day. I do not want it to turn back on each time the ignition is cycled off and on again. Does anyone know a way to do this? On my Mini Cooper S there was an aftrr market electronic circuit that changed the default for ignition turn. At ignition turn ON the stability control was OFF. The switch was then used to turn it on stability control ON. The default condition could also be cahnged back to the OEM set up easily. This arrangement would be ideal for the Cayman S . Ideas anyone?

To be honest, there is no way to totally disable PSM. The way the car comes, as you indicated, when you manually turn off PSM, it defaults to "On" when you restart the car. But as I said, there is no way to totally disable PSM. It is always on in the background even when you switch it off. Turning PSM off just allows the program tolerances to be increased allowing you to drive more aggressively without it kicking in. But if you really get out of control, even with PSM switched off, it will kick in and stabilize the car if it thinks you're in trouble. There might be some programing in PIWIS that would allow you to totally disable the switch, to where you have to manually switch PSM on, but I doubt it. That would be too much of a liability for PCNA, but you can ask your service adviser if PIWIS has that option in the programming.

What about placing your car into sport mode? Trust me you are not going to be faster with PSM off, if you are hitting PSM with it in off or sport mode it is because you are not driving smoothly and getting out of bounds which is going to make you slower not faster. There may be an ECU tuning solution coming soon that will let you put PSM into sport mode all the time (regardless of whether or not you have sport button) and I'll have to check if it will turn off and keep PSM off, I'm not sure about that one. Of course if completely off there goes your safety net too.

On the track, I think of PSM as training wheels. And if you can't drive consistently with it staying off, then you shouldn't turn it off at all. IMHO.

Mantis Sport told me that when you turn PSM off it will automatically engage when the trurn angle and breaking reach a certain point. I have experienced this at sebring on certain turns. Mantis said they got around this by: "There are two switched on the brake pedal, one for the lights and one for PSM, disconnect the PSM switch and you should be in trail braking heaven." I'll be trying this Aug 4th and 5th at Sebring and will report what I experience. :cheers: GuyC

Looking forward to your report Guyc, I am looking forward to your report.

My Experience with PSM Off At a recent Autocross event I spent the morning session (5 runs) with the PSM on. There were several sections where the PSM would cut the throttle out which was very annoying. I still achieved respectable times. For the afternoon session I turned the PSM off. On my first run (with the tires cold) I swapped ends at the first 90 degree turn :banana: . After a couple more runs I was consistently improving my times because I could get the car to oversteer at the proper point in order to align myself for the next section. I was in power slide heaven :drivingskid: . The car started to feel like it was an extension of my body. :dance:

According to Mantis, there is no way to really disable PSM, and that includes pulling relays, etc. Forget everything you ever learned about trail braking...

Last weekend was spent at Sebring driving with the PSM off and giving the 996's, GT3 's and 911 's a hard time. My love of this ride is growing more and more at each event. My car does not have PASM but is setup with PSS9's. But before I give you the details, let me give you the disclaimer. This is not something a new owner or first time Porsche owner should attempt. This is not something that should be disabled for street use. This should only be done for track events and for drivers with many years of track driving experience. NOT FOR A NOVICE. Porsche put these abilities into the car for safety and protection of the driver. They should not be changed or tampered with for any car used on the street or any inexperienced driver. My car is used primarily on the track and I have almost 10 years of track experience and over 34 years of driving different production Porsche 's. This doesn't make me an expert, just experienced. Ok, all we did was disengage the PSM brake override by disconnecting the two wires at the brake pedal as Mantis Sport had suggested. We determined the correct two wires by reviewing the wiring diagram and pulling the connections. Simple. Now, I'm not a really technical guy and I can't explain the effects of slip angle, g-force etc. But I can tell you that PSM did not engage at anytime on the track this weekend as it did previously. Back in June at Sebring with the PSM off but the brake override fucntioning I experienced quite a few corners where after I broke through the corner the PSM would engage and kill the throttle until the car settled. Most annoying. But this last weekend I could brake through the same corners and accellerate immediately without PSM engaging. So that's my story and I'm sticking to it. :cheers: GuyC

Can you be more specific with some details on the wires to disconnect?

Please clarify! I know from experience that if the switch in front of the brake pedal is made to think it is always on or always off while driving, it will disable PSM, ABS, and sport chrono- not what I want to do. Do you do something special, or do you just run without ABS, SC, etc?

I'm a new member of this forum since I just bought 2006 Cayman S without sports chrono or PASM . When I drove it on a racing track, I experienced PSM was reactivated under braking so I searched the Internet to find how to disable PSM completely without losing ABS. I found many discussion threads talking about this issue but I was surprised that I couldn't find any actual solution for this. Then I found this thread. It was kind of my last hope since this was the only one I could find which looked like have an actual solution. So, I took a look at my Cayman 's brake pedal and removed a connector I found but it was for stopping lights... According to guyc's post, there should be another connector on the pedal but I couldn't find any!! Maybe his Cayman was different type... It sounds strange though that there is another connector just to check if the brake is on or not since the stopping light switch can be used for it... So, I obtained a service manual and took a look at the wiring diagrams. The stopping light switch goes to PSM control unit but nothing similar does. So, I believe PSM uses that switch to judge the brake status at least for my model. Maybe I could kill PSM by pulling off the switch but I need it not to get hit from behind... So, I had to find another way to do it now. One possibility was pulling off a brake fluid level gauge connector since that signal goes to the CU as well. Disconnecting that might fail PSM so I tried it but it didn't work. I remember some old Toyota or Lexus can make VSC off by this but not for Cayman ... Then I was looking for something else and found really good candidate. It was a connector for what Porsche calls "rotation rate sensor". It's located on a floor under center console. Mabye, I could pull out a steering angle sensor connector to kill PSM as well but this is much easier to access than that or even the brake fluid tank (you need to remove the whole cover in a front trunk to access the connector). There is a cover at left front side of center consol which can be removed by a torx wrench then you will see a sensor and there is a connector attached to. Just pulling off it then vola! PSM is completely off! You will see "PSM failure" on an information window but no beeping or anything. It's always off too that the originator of this topic wanted to do. Of course PSM comes back once you put the connector back. I testdrove and confirmed that it kills PSM but keeps ABS alive In my case, it was tough to remove the connector without removing the whole sensor from the floor (10mm socket, 1/4" wrench will be needed). The connector lock is so tight that I needed to insert small flat head between the lock. As other members warned already, I DON'T recommend to do this unless you are an experienced driver and know how to control a car. I don't guarantee if this won't cause any trouble later either. I'm a professional test driver and know what I'm doing. Actually pulling off a sensor connector is what we do to disable stability control in some cases. Disabling stability control completely is getting difficult more and more... If nothing works, we pull out ABS fuse Anyway I know this is old topc but I hope this info. helps other drivers who want to have more control in their Porsche

Thanks to you, hawkyama- I've wondered about this ever since I first had the gas pedal pulled out from under me by PSM. Next time I screw my balls back on for an extended session with it off, I will now know how to do it. Great write-up.

:drivingskid:

> chas365 I'm glad if my post helps Actually I think turning off PSM by pushing "PSM off" switch is probably good enough just to run quickly. The reason I decided to kill PSM was that I didn't like a feeling when the system grabbed the front brake and made the car stabilized though I was trail braking into a corner to initiate drift I still can make the car O/S but the feeling is just not natural... >Walter Geez! I wish I could've found that post first. It was weird that I couldn't find any post like that. I've spent too long time underneath of the steering column to find the switch... Anyhow, I think my post has more details for somebody who wants to do the same thing and actually I ended up exactly the same solution as glenn's Installed a switch so that I can disable PSM completely when I need Can't wait for a next run on a race track!

This is kind of follow up of my previous post. I went to a racing track this week and tried the switch. It worked flawlessly I also tried to pull out a ABS fuse to see what will happen but this wasn't a good idea. It changes brake bias to rear too much because of EBD (Electronic Brake-force Distribution) failure. It was felt like I pull e-brake when I entered a corner I don't recommend doing this to kill PSM completely...

I did it too, My question is when I turn my ground wire switch to off Sport Mode looses power as well and Light goes out as well as PASM Shock light goes out. So if they are off am I loosing engine mapping and stiffer suspension? Now you have to decide whos more important Any ideas to have power to PASM and sport mode without Yaw sensor active?

For Gen 2 cars napleton has a program to turn off PSM. It's usedfor Interseries cars

I added a switch (see photo) on the PSM ground wire. Without it, even with the OE PSM off, the car would add braking to the rear wheels - - burning up brakes.

Can anyone post pics or which wire you are putting the PSM disable switch on and where you mounted your switch. I'd want it in an inconspicous place as my car is not just a track car. Better yet, if anyone wanted to post an article, I'm sure it would be appreciated by many.

Sounds good! Can you tell me where you uninterrupted the ground?

Send me a pm and I will work you through it View attachment 26646

Maybe you guys might like to consider offering a kit which will enable us Gen 2 owners to disable the PSM bit (maybe its the same thing??) so we can get our cars on a standard RWD Dyno. 987.2 cars cant exceed 4500RPM with only the rear wheels turning. Just a few members cars dont seem have this limitation.

Pm replied

So I am trying to figure this out. If the method to employ is to add a switch for the ground on the PSM CU, that looks like pin 1 here: Detail shows color as Brown (I certainly hope so!) And the PSM Control Unit location is in the front on the driver's side.

Tap into the Bosch sensor that we spoke about. The wire is gray with a brown line. It's the closet to the drivers right foot on the harness plug . View attachment 26735 View attachment 26736

So I wired up a switch as noted above. Indeed, this does completely disable PSM. However, on my PASM equipped car there is a bad side effect - no Sport Mode. I presume PASM needs the yaw sensor or perhaps all of PSM working, and the Sport Mode requires PASM to work - so this combination is not supported by the method. Darn.

Do you get any error messages on the dash?

I have been watching this thread for awhile now, I got lucky (I guess) that my PSM and ABS both turned off (i think it had to do with my battery dying) and now PSM nor ABS interrupt me on the track, the only thing is i dont really allow anyone else to drive my car because i am worried that they will not understand what to do in emergency situations, has this happend to anyone else. The brakes are great, i can really brake deep on the track and i feel all the force go to the front, unlike what a comment said that it felt like pulling the ebrake, I know this has to do with electronics so if anyone could fill me with some insight as i only am familiar with mechanics and racing. - Jerry

I dont know but maybe my car is different??? I leave PSM on and Sport mode on and I dont get any of these things mentioned above happening. I do run R Spec Yokohama A050 soft which are more grippy than regular slicks with -2 deg camber. A050s' are like qualifying tyres. I often drive it at 10/10ths and the PSM hardly ever activates. ABS activates but thats ok because it just shortens the braking distance even more. For trail braking and corner exit its all just perfect. However I do note that when I used to drive a gen 1 car on the same track and with no LSD it was inferior in comparison. PSM (sport mode on) would hinder a lot. If I had no sport mode it was rather hopeless. If one has no sport mode or no LSD or weak tyres then I can understand, but otherwise not. Oh and BTW, I had a bad track day once with PSM going nuts. It was found that I had a faulty sensor switch on the clutch. All good now .

i guess the only downside is that in the tiptronic you cant hold the gear you want because you can no longer select PSM

Do you get PSM and ABS warning message on the dash? If so, I believe the wheel speed sensor isn't working. Pulling of one of those generally kills ABS and stability control but not EBD.