There should be a thumb operated clicky switch on the 'front' of the wiper stalk facing you that sets the sensitivity of the wipers. They're not auto until you activate them though - IIRC the stalk has to be one click up from level, then you have to either flick it down and up, or just flick the sensitivity switch up and down. After that the auto mode is on. You do have to do it again the next time you drive the car though as it disarms when you switch the ignition off.