306 gti table taillight

friends, I washed the engine, there was no problem, but after going for about 5 km, the stop light started to blush and it was burning right now, there is no abnormality in the car at the moment, they went to the service, they said it was from the fan cassette, they said that it could dry itself, but it was still 3 days.

are both burning or just someone ??