This indicator lamp lights up. What could be the cause of this?

The indicator lamp you see is a warning signal for issues related to the vehicle's tire pressure or wheel setup.

When it lights up, it typically suggests two main causes:

1. **Low Tire Pressure**: This can indicate that one or more tires have insufficient inflation. Maintaining proper tire pressure is crucial for safety, fuel efficiency, and tire longevity.

2. **Recent Wheel Change**: If you’ve recently swapped out tires, this indicator may activate as part of the system recalibrating itself to recognize the new tire conditions.

Both of these factors are important under German traffic regulations, which emphasize the need for vehicles to be in safe operating condition. Correct tire pressure is vital for optimal handling and braking performance, hence the need for attention when this lamp is lit. Ignoring it could lead to increased wear or even potential tire failure.