TIRE-PRESSURE MONITORING SYSTEM

A computer includes a processor and a memory, and the memory stores instructions executable by the processor to determine an update function based on data indicating pressure in a tire of a vehicle over a most-recent time period, determine a current test statistic for the most-recent time period, and, in response to the current test statistic exceeding a threshold, output a message indicating low pressure of the tire. The update function lacks an input of temperature. The current test statistic is a function of the update function and a previous test statistic. The previous test statistic is for an immediately previous time period from the most-recent time period.