I just had the dreaded 'Tyre Pressure System Fault' show up, so I was researching these, and it seems that some online sites show the 53004 as a newer replacement for the 53001.
(Since then I've checked the sensors and they seem to be good, so I need to check that wiring harness behind the front bumper, argh.)

 

The TPMS on my XKR started acting up a couple of weeks ago on a trip to Dallas. TPMS display comes up, red mark goes around the car a couple of times then it goes off for a few minutes. I'm thinking the batteries are running down.

 

The batteries sealed within the TPMS are estimated to last 8 to 10 years.

 

Thanks Richard, looks like it is time to ante up for new Siemens all around.

 

I had the TPMS problem on my 13 XKR. Solved under warranty by replacing the TPMS module.