Interior lighting only goes for a short time

A good evening in the round! I have a question regarding the interior lighting, and this is the problem with me that the reading lamps front and back incl. on/off switch for the complete interior lighting only function when I pull the fuse (10A) and plug it back in. They then work only for a short moment (filled about 10.min). I open or close the doors or light the front lamps incl. footroom lighting normal. The problem only concerns the reading lamps. Have the lamp unit changed completely, but without success. Are these controlled by a separate control unit? Or a ralais? Vehicle is a V70 II 2.4T Bj. 2001 petrol. Thank you in advance. Greetings