I found this answer online
Hi Edi,
Same answer I gave to Eliza,
SensorControl red light for the models BGS5525, BGS5ZOOAU, BGS5SIL66AU comes up in three different occasions:
1) If the machine is self cleaning. It stops, cleans for about 20s and then starts again.
2) If there is a blockage. The indicator flashes three times in quick succession, even though the filters are clean, this is probably due to a dirty fluff filter or a blockage. In this case, the vacuum automatically adjusts to the lowest power setting and the indicator lights up red permanently. Please check that there is not any blockage inside the metallic rod (you can see through) and the hose (you can make a 5c coin run from one side to the other).
3) If the round filter needs to be cleaned:
-take the mesh cover off and tap the filter to dislodge the dust.
-for an additional and more deep clean you can wash the filter but make sure that dries up completely, it will take over 24H, don't use any soap or any detergent, don't brush the filter off.
Hope this can help.
