One of the primary reasons for a blinking red light on a Bosch dishwasher is a water supply problem. The dishwasher requires a steady and sufficient supply of water to function correctly. Bosch dishwasher blinking red light Check the water inlet valve and ensure it is fully open and free from any blockages. Inspect the water supply hose for kinks or leaks that may restrict water flow. If the dishwasher doesn't receive enough water, the red light may blink to indicate a fault.