Thank you für your answer SimoneR. I found out that the electric power light is only shining, when the ePvL is swiched on. Since I have a solar system on the roof, the previous owner told me, that I should swich off the ePvL. Is this information correct in your eyes? To be hones I do not understand ...

Dear Readers, hope I can find help here. If I plug in the electric power into my camper the sign of the MTP_LED Mod. 2016 is not shining. I expect that the ligth behind the panel is damaged. How can I remove the front panel to check the lights? Would be very pleased to get an answer. Thanks and Best...