We determine the prioritization of processes and tasks in automotive companies. The methodology of Failure Mode Analysis and Effects was applied, the purpose of the FMEA is to take actions to eliminate or reduce failures, starting with the highest-priority ones in order to efficiently identify all possible failures in a design, a manufacturing or assembly process, or a product or service. The traditional Failure Mode Analysis and Effects methodology was applied to four different processes in the companies of the automotive industry, finding deficiencies in the calculation of the Risk Priority Number. Therefore, the calculation of the Risk Priority Number is modified in the methodology, implementing additional steps, adding a weight to the calculation of the risk priority number. The weighting was determined in the cost function associated with a failure scenario within the process. To do this, the cost of the severity of a defect was calculated, such as the effects on the customer, warranty costs, scrap, etc. Secondly, the cost of the occurrence was determined, which indicates what the company is going through when the defect is repaired. The cost of detecting a failure in the system is applied. Finally, these factors are balanced. Finally, a comparison is made against the traditional methodology to identify the improvement in the prioritization of tasks of failure modes that represent a greater impact on the economy of the company and have a consistent control plan.