Not something that I cannot live with if I can't solve it but after recently had my spare alloy repaired and a new tire fitted I returned it to the storage space in the rear. Since then when I come to start the car I get a low pressure on spare warning from TPMS. It only stays on for a couple of minutes and the pressure is correct so I thought it would have calibrated itself by now. Any thoughts guys? Agueroooooooooo. 93-20
I swear you will never see anything like this ever again....watch it..drink it in.

Had this issue, make sure the spare is inflated to the max possible pressure for where it potentially could be used which is fully loaded on the rear. With 22 tyres this is 47psi so to allow for error I put 48-50 in, maybe different for other sizes.

The system is calibrated for worst case scenario.

Your TPM sensor in your spare might be low battery, and covered in boot area can give weak signal to receiver , this will trigger warning. Replace sensor.