Peugeot 3008 Rain Light Sensor Fault

Sounds like a faulty rain-light sensor. Those systems all use it. Is your windshield sensor original, or has it been replaced? Aftermarket sensors sometimes cause issues.

Thanks. As far as I know, the windshield and sensor are original. No front-end damage. I don't know much about the sensor. Is there a way to diagnose it, or does it just need replacing?

Hard to say without proper equipment. But bubbles under the gel pad on the windshield where the rain sensor sits are a known problem on the 3008. The bubbles mess with the sensor's ability to 'see' properly, which can lead to an electrical fault. I'd recommend getting it checked at a workshop.

Thanks for the advice. It was the rain-light sensor, just like you said, with the bubbles under the gel pad. Repair cost 62€! Appreciate the help!