When a vehicle comes in for tire service or TPMS warning light being on, it’s a good idea to perform an inspection also.
Test the TPMS sensors using a tool before touching the tires. Any parts that fail testing, show a low battery or inaccurate pressure/temp readings should be replaced.

a service-kit should always be installed whenever a tire is removed for service or replacement. for metal-stem sensors (clamp-in), that involves replacing the nut, core, cap & grommet. For snap-ins, replace the entire rubber stem.

If the metal valve is going to be re-used, check it for cracks or corrosion. If the sensor hasn’t been serviced in a long time, the nut can rust to the stem and come apart when loosened. Newer sensors typically have replaceable stems, while older units usually don’t.

Sensors that have been accidentally damaged by bead brakers or that came loose and rolled around inside tire should be replaced. Also if the plastic case is cracked or case seal is leaking, install a new sensor unit.