PSM Faulty and Air Suspension Faulty warning captions on start up

[911since94]

2005 3.2 V6 Tiptronic Cayenne
Would be grateful for some advice here.
Have both warning messages on start up. There's no effect at the moment on either PSM or Air Suspension. Took it to an Indy who said it was more than likely the brake pressure sensor (on the bottom of master cylinder) but couldn't promise the replacement would solve the issue. Read elsewhere that it could be wiring harness problem or MAF sensor. The amber warning exclamation mark stays on on the right hand dial and the circle with triangle also in amber on the left. The messages just appear on start up.

The brake pressure sensor apparently takes 4-5 hours to replace.
Firstly, has anyone had this problem and got it fixed and secondly does 4-5 hours seem reasonable to replace the aforementioned sensor?

Any comments gratefully received. Thanks

 

[Mark_Mko]

I've just been reading through your post , did you ever get this sorted ?
if not I was going to ask you if the warnings are on before cranking or only once the engine has started?

 

[Laurence Gibbs]

Do a search on Rennlist or via google. Most likely the crimped connections in the wiring loom under either drivers or passenger side carpet . Check for wet carpets. Ideally you need a system tester to tell you exactly what faults you have.