A solid line may be crossed over if “this is required for the vehicle to pass an obstruction on the road” (Swedish Road Traffic Ordinance). Perhaps the car is abandoned? It would not be reasonable for you to be stationary and blocking the entire road just because you are not allowed to temporarily cross over the solid line.
You should primarily endeavour not to cross the solid line, but if you have to, you are allowed to do so.
Körkortonline.se offers driving licence theory tests. This is an example of an explanation of a test question. English (driving licence questions in Sweden), Swedish (driving licence questions in Sweden) and Arabic (driving licence questions in Sweden).
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