Mini Cabrio windshield washer issue

That's a frustrating one. A low windshield wiper fluid level is definitely the most common cause for that warning. Have you checked the reservoir under the hood recently to see if it's actually empty? Even if it's not completely empty, a faulty sensor could also trigger the light. Another thing to consider is the windshield washer pump itself; if it's failing, it might not be able to draw fluid properly, even if the reservoir is full. Does the windshield washer motor make any sound when you try to spray the windshield?

Thank you for the suggestions. I've checked the reservoir visually, and it appeared to be nearly empty. However, I did not specifically check the sensor. Could you elaborate on how to test the sensor's functionality? Also, if the pump is the issue, is there a straightforward way to diagnose it without specialized equipment?

Okay, based on that information, it does sound highly probable that the low fluid level was the primary issue. The sensor is a float switch, a pretty simple piece of equipment, but sometimes they get stuck. If the system still doesn't work after you fill it, you would need a multimeter to test it for continuity. Given that you found the reservoir almost empty, I'd recommend just filling the wiper fluid first. If the windshield washer still doesn't work after filling the reservoir, and if you don't have experience working with electrical parts of a vehicle, I would recommend a workshop visit.

Thank you for your input and assistance. As suspected, the warning light was due to an empty wiper fluid reservoir. After refilling it with windshield cleaner, the system is operating normally again and the error message has disappeared. The cost for the windshield cleaning fluid was approximately 25€.