Discussion
Intermittent PSM failure comes up on multi screen on 981. Seems to be linked to a hot footwell on cold days. Blast cooler air at it and stop, switch off completely - key out - restart and it has cleared and will not do it again for days, or an hour later with the heater set to 'feet' and toasty.
OPC is miles away so not a case of zip it round and let them tinker, without a lot of planning. Anyone else experienced anything like this?
Pope if you are out there in the ether I would appreciate your input.
I am extremely suspicious of the brake switch,
A) because it is multi function
B) because it is a proximity type and the heat could be altering it's proximity sensing.
Weeks can go by without it happening.
Message is 'Warning PSM Failure' followed by 'Warning Auto Start Stop Failure'. Then, maybe the brakes stay slightly applied, or not depending on how it feels. Twice in six months and always on cold days.
I know it needs OPC love and care but I can't get it to then for about three weeks.
OPC is miles away so not a case of zip it round and let them tinker, without a lot of planning. Anyone else experienced anything like this?
Pope if you are out there in the ether I would appreciate your input.
I am extremely suspicious of the brake switch,
A) because it is multi function
B) because it is a proximity type and the heat could be altering it's proximity sensing.
Weeks can go by without it happening.
Message is 'Warning PSM Failure' followed by 'Warning Auto Start Stop Failure'. Then, maybe the brakes stay slightly applied, or not depending on how it feels. Twice in six months and always on cold days.
I know it needs OPC love and care but I can't get it to then for about three weeks.
I've just had this yesterday while driving london to Scotland - on and off for 350 miles in the rain - the two yellow warning messages (PSM LOSS drive gently - followed soon by Auto Stop/Start disabled)
Nice on Xmas day.......not.
As memory serves me correctly I did have the heater on in the footwell to begin with, but turned it off. After every short rest stop I took the messages disappeared but came back after 10 mins.
Brake pedal had been getting "sticky" the last few days and today at times definitely felt like the brakes were ever so slightly on, especially at the end of the journey.
Some history.........
My local certified Porsche specialist fixed the brake pedal sticking with WD40 and wiggling the pedals last year I think., just around town, but I didn't get the PSM messages.
Tomorrow I'll try WD40 again, (and no heater) tomorrow and see what happens with the messages.
If it works I'll let you know.
Nice on Xmas day.......not.
As memory serves me correctly I did have the heater on in the footwell to begin with, but turned it off. After every short rest stop I took the messages disappeared but came back after 10 mins.
Brake pedal had been getting "sticky" the last few days and today at times definitely felt like the brakes were ever so slightly on, especially at the end of the journey.
Some history.........
My local certified Porsche specialist fixed the brake pedal sticking with WD40 and wiggling the pedals last year I think., just around town, but I didn't get the PSM messages.
Tomorrow I'll try WD40 again, (and no heater) tomorrow and see what happens with the messages.
If it works I'll let you know.
Run the car with heater on footwell for 20 mins or so then check how free the brake pedal feels , as is mentioned above it was a known fault where the plastic bushes on the pedal shaft tighten up with heat.
Usually best to have the bushes and plastic shaft replaced as in the worst cases the brake stuck on enough that the brakes got very hot.
An independant or opc can replace if the car is out of warrenty.
Usually best to have the bushes and plastic shaft replaced as in the worst cases the brake stuck on enough that the brakes got very hot.
An independant or opc can replace if the car is out of warrenty.
Thanks for suggestion Demort.
Today, put WD40 all over the brake pedal mechanism and hey presto no more more PSM messages or brake pedal sticking at all for 20 miles. No heater on footwell.
On the return 20 mile journey I purposely put the heater on in the footwell and after a while pedal started sticking again - but no PSM or auto stop start messages.
Turned footwell fan to LO and sticking seemed to get better, but bored of the testing so came home.
Still - no messages today after having them all day yesterday.
So. - a workaround till I can get it put in OPC or NOPC - but what a desperately poor design fault!!
Today, put WD40 all over the brake pedal mechanism and hey presto no more more PSM messages or brake pedal sticking at all for 20 miles. No heater on footwell.
On the return 20 mile journey I purposely put the heater on in the footwell and after a while pedal started sticking again - but no PSM or auto stop start messages.
Turned footwell fan to LO and sticking seemed to get better, but bored of the testing so came home.
Still - no messages today after having them all day yesterday.
So. - a workaround till I can get it put in OPC or NOPC - but what a desperately poor design fault!!
Edited by Paxto on Saturday 26th December 15:51
Porsche altered the bushes on the pedal shaft as soon as they became aware of the fault and issued a recall for what they thought were the affected cars so i think to be fair they did their best , as with anything new problems can arrise.
You wont always get the Psm warning as the car has to see the pedal switch activated over a test period but getting the bushes replaced is the best action.
If you have a Pdk then its a cheaper job than a manuel as 1 less pedal and set of bushes.
I think although dont quote me 0n this, its a 1.5 hour job on a Pdk.
You wont always get the Psm warning as the car has to see the pedal switch activated over a test period but getting the bushes replaced is the best action.
If you have a Pdk then its a cheaper job than a manuel as 1 less pedal and set of bushes.
I think although dont quote me 0n this, its a 1.5 hour job on a Pdk.
Simple engineering flowchart from Planet-9 thread on this subject. (They do Boxsters too though)
http://www.cyclelicio.us/wp-content/uploads/2011/1...
Made me laugh.
http://www.cyclelicio.us/wp-content/uploads/2011/1...
Made me laugh.
Paxto said:
Simple engineering flowchart from Planet-9 thread on this subject. (They do Boxsters too though)
http://www.cyclelicio.us/wp-content/uploads/2011/1...
Made me laugh.
Rofl , sums up being a Mechanic nicely i think http://www.cyclelicio.us/wp-content/uploads/2011/1...
Made me laugh.

I bought my Boxster new in July 2013. Only just had this problem happen to me, so the car was out of the 2 year warranty.
Porsche fixed it and gave me a "goodwill" discount of 60%, so total cost was ~£125.
Words fail me. I paid ~£65k for a well-specced car, there is a design flaw with a part they use. Instead of doing the right thing and replacing it they flog the customer for some more money.
If I wanted to I could recover the ~£125 from them under the Sale of Goods Act etc.
The car has had 5 weeks off the road due to warranty repairs in the first 2 years of ownership. My last Boxster had 2 RMS repairs in the first 2 years.
Porsche need to get their act together. This will be my last Porsche. (Apart from maybe a classic!) My family barge is being replaced this year, it will either be a Merc GL63, BMW X5M or Tesla X. There could have been a Cayenne Turbo on that list, but I need a reliable car and I don't like to feel that I'm getting shafted and having to pay for recalls.
Porsche fixed it and gave me a "goodwill" discount of 60%, so total cost was ~£125.
Words fail me. I paid ~£65k for a well-specced car, there is a design flaw with a part they use. Instead of doing the right thing and replacing it they flog the customer for some more money.
If I wanted to I could recover the ~£125 from them under the Sale of Goods Act etc.
The car has had 5 weeks off the road due to warranty repairs in the first 2 years of ownership. My last Boxster had 2 RMS repairs in the first 2 years.
Porsche need to get their act together. This will be my last Porsche. (Apart from maybe a classic!) My family barge is being replaced this year, it will either be a Merc GL63, BMW X5M or Tesla X. There could have been a Cayenne Turbo on that list, but I need a reliable car and I don't like to feel that I'm getting shafted and having to pay for recalls.
When I found this thread I thought I'd found the answer to the error that flashed up. Had exactly the same thing including the Start/stop business. Took it into the PC and they did a diagnostics on it and said it was the coil on No.3 cylinder. What's that got to do with the PSM?? Told them what I read on here and they knew about that issue with the pedal too. Anyway they changed the coil under warranty. Apparently a lot of faults will trigger the PSM error message and the Start/Stop warning although not being related to the PSM. Sounds like a load of BS to me.
Mine's a 2015 Cayman S btw
Mine's a 2015 Cayman S btw
ECU's are networked via CAN BUS, if a fault occurs that is detrimental to correct running, various systems can respond - usually with soft shutdown and a dash warning.
PSM is a safety system that can control or overide the throttle to regulate traction; if a fault occurs that affects engine power the system is shut down as a result. Many times, PSM will deactivate way before the Check Engine light signifies a fault. No BS.
Example; 996 turbo intake air leaks or MAF sensor issue; first sign? Intermittent PSM failure warning......
PSM is a safety system that can control or overide the throttle to regulate traction; if a fault occurs that affects engine power the system is shut down as a result. Many times, PSM will deactivate way before the Check Engine light signifies a fault. No BS.
Example; 996 turbo intake air leaks or MAF sensor issue; first sign? Intermittent PSM failure warning......
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