Help. 850 won’t start.

Hello, my moose just doesn’t want to start. 850 Combi from 12/1996 with Beziner 144hp. Battery is charged. I can operate the ignition normally, the tell-tales also start at stage II (motor control lamp and ABS also off again), as soon as I turn the ignition key into stage III, the dipped light goes off, it does not clack once briefly and more. If I jump back the ignition key into stage II, the dipped light goes on again. Last week the car is two m al as described above did not start, I then waved on a few cables and pressed on all fuses, then it started again quite normally. Also quite normal without any stuttering or speed fluctuations 550 km with tank stops and jumps without problems. After that only overnight and following day put off and now stop as described above. I have now also once pulled the petrol pump relay and inserted again, but nothing changes. If I the ignition on II spins, but it also buzzes briefly, sounds like gasoline is being pumped. Even knocking against starters didn’t help either. He does not report any error code at the socket under the coin compartment. To check the cable it is now too dark, I will make tomorrow. Does anyone else have advice for me? Is it normal that the dipped light runs out when turning the ignition key from stage II to III? CSevenoak