A visual, rear viewing and rain sensing system for a vehicle comprising a windshield and a button connected to the windshield, with the button having a peripheral body defining an open area in a middle section of the button. The visual, rear viewing and rain sensing system further includes a rain sensor located in the middle section and an interior rearview mirror system connected to the button. The rain sensor is operatively coupled to the windshield independent of the interior rearview mirror system. At least a portion of the rain sensor is no longer operatively coupled to the windshield as the interior rearview mirror system is detached from the button.