What would cause water noise from behind instrument on toyta previa?

Water noise from behind the instrument panel in a Toyota Previa could be caused by a few factors, such as a clogged or damaged windshield drainage system, which can lead to water pooling and sloshing around. Additionally, a malfunctioning heater core may leak coolant, creating a similar sound. It's also possible that water has accumulated in the cabin due to a seal failure or a blocked drainage tube. Inspecting these areas can help identify the source of the noise.