My Center Brake light is playing up. I get the warning on the dashboard that prompts me to replace the "bulb". At times this indicator does not come on for about 30 minutes after a cold start. Before the indicator comes on, the brake lights work fine. It stops working one the dashboard warning shows up. Car is only 2 years old and under manfacturer's warranty.

Who's experience this before?
Should I replace the whole LED unit?
Is this part covered by warranty?

Thanks.