I got a used set of XF rims for my US-spec '08 X358. Now I need to outfit them with 4x TPMS sensors.

Since it's US-spec (although located in Germany now), I suspect the TPMS is running on 315 MHz. All the Jaguar documentation I can find states "data is transmitted by RF data signals at either 315 MHz or 433 MHz dependant (sic) on market requirements"; it is completely silent on whether data transmitted (by the TPMS sensor in the wheels) on either frequency is also received correctly by any TPMS module (in the car), or whether the transmission frequency needs to match the car's receiving frequency...

More clearly: Can I replace the (suspected to be 315 MHz) TPMS sensors with easier-to-source 433 MHz units, and will they work in my US-spec XJ?

(I know about the "TPMS is on same frequency as key fob" and the "EU is on 433 MHz", but my question is whether the TPMS module is compatible with either frequency.)

 

Why don't you stop by tire shop with your car and current wheels and ask them to check frequency? As far as I know there are tools that can identify frequency of TPMS sensors. Alternatevly you can break the bead on one of current wheels and pull sensor out. Frequency will be on the sensor.
Here you go:
https://www.google.com/search?q=are+...YiJzcdlE,st:48

 

I just installed replacement TPMS sensors in one of my cars (non Jaguar) and used the Autel MX series dual frequency sensors at about $25 each. I also bought an Autel TPMS tool for about $160 to program the sensors. The programming is easy enough, you just copy the codes from the OBD2 to the tool and then program them into the new sensors before installation. The hardest part is breaking the bead on the tires. It cost me about what a shop would do it for and now I have a TPMS tool that can check the batteries on any sensor, program sensors and also check that key fob remotes are transmitting.

 

433 sensors will not operate on your US market Jag and it is not possible to reflash your TPMS module to operate with 433 sensors by US vin of your Jag.

 

Thank you @PeterX358!
So I understand that it is the TPMS module itself that defines the operating frequency.

Now thinking ahead... if I had to switch frequency (who knows; German TÜV seems to be tightening the screws)... would it be a swap of the TPMS module only, or are the antennas frequency-specific too?

 

There's a slight discrepancy here: what's behind the wheels aren't antennas, but initators /C2C24208/, and they're market-independent. There's only one antenna and it varies depending on the market /C2C37076 - 433/, and of course the module also /C2C37060 - 433/. I have no idea if a module from another vehicle will work in yours, but if you try to program it using your car's VIN, it won't be possible, you'll get a message: Not for this market.