Until recently, I have been able to open the driver's door with the primary key (to preserve the memory settings and because the house key is on the key ring), start it with the secondary key, then lock the vehicle with the main key. Now after starting the Cayenne, the key will not lock the door. This entire sequence is used so that it warms-up in cold weather. There is virtually no risk of theft where I live, but I still prefer the peace of mind knowing the vehicle is locked. Any thoughts? Thanks.

 

I use the same warm up technique.
Could be lock cylinder intermittent failure. My Touareg door lock cylinder started to act up like this and then I believe mechanically failed. I just ordered a replacement. Hope to complete replacement next week.

 

Thank you for the reply.