The article discusses the causes of failures of trucks based on statistical data obtained from GITD and a transport company. Knowledge of the results of the conducted analyzes will allow to indicate the components or parts of vehicles that are most often damaged. Thanks to such information, it will be possible to prevent vehicle stoppages caused by defects in the future and to minimize the risk posed by a failure.

This paper discusses the matter of fault detection by the diagnosticians of a Regional Vehicle Inspection Station (RVIS) in trucks. The analysis data were obtained directly from RVIS. The produced results were presented as bar graphs indicating the trend change from 2014 to 2018. Thus obtained trends were described by formulae and used to calculate the probability of a fault from the analysed group appearing. The obtained data dependency can be used to calculate the probability of a fault appearing in a truck during a year of operation.