PSM Unwanted Operation - Any Thoughts?

[Chri4S]

Hi Guys,

I am still new to the 911 Experience, 3 months in C4S 2003, so wonder if any of you can shed a little light on the PSM. I have looked back at earlier posts but didn't notice any on this point.

It has happened a few times now where the PSM has operated at a time when I have been well within the limits of the car. Yesterday I did a wonderful 40 mins on twisty roads all well behaved and then on a tame corner it cut in. The road surface was not rough that I noticed.

It has only happened on right handers from memory. It's a bit unnerving when you are not expecting it.

Is it possible that there is a problem with one of the sensors? Or maybe the system isnt infallible (but that is 3 or 4 times now)?

I have the Porsche extended warranty and PSM does seem to be covered. I will maybe get them to check it at the next imminent service, and hope they dont charge for investigating it and tell me it's ok.

Any thoughts chaps?

[GreigM]

Tyre pressures? If one of your tyres is down it can make the system think the tyres are spinning.

The only other thing I can think of would be if one of the wheels is lifting off the tarmac and spinning - PSM will cut engine power if it detects this.

[tuckerossi]

I think PSM is covered by the OPC warranty, its the PCM option that is excluded which is probably causing some confusion.

[Don]

I have never, ever had PSM do anything that I wasn't deeply grateful it did! This includes heaving the car around race circuits on track days...

If your car is doing unexpected things regularly get it checked out: I have never had the PSM light come on whilst road driving....except whilst driving like a total cock and needing to brake very hard and steer on a surface that "suddenly" (I should have expected it!) became very slippery: it took hours to get all the cowshit off the bottom of the car. Oh...once I had the passenger side rear wheel on a grassy bank one the drivers side rear on the road. PSM came on pulling away from that for a moment or two. That was it!

[Chri4S]

I did find one front tyre down 3 or 4 psi!

Hope your right. Will find out soon enough.

Thanks

[GreenV8S]

I don't know how your PSM system works, but I've had some strange behaviour with a TC system that used a wheel speed sensor on each corner, when one of the sensors went intermittent. It turned out that the sensor was slightly wrongly adjusted, and there was just enough bearing flex to put it out of range on some corners. May be a red herring, but perhaps worth checking?