How can I troubleshoot a tub spout diverter that is not working properly?

To troubleshoot a tub spout diverter that is not working properly, first check for any blockages or debris that may be preventing it from functioning correctly. If there are no visible obstructions, the diverter valve may need to be replaced. You can do this by turning off the water supply to the tub, removing the diverter valve, and installing a new one according to the manufacturer's instructions.