l am having an electrical problem with my 1992 Saab 900. The regular low-beam headlights are not working. l do not think they're blown, because this has happened before and they started working again.Parking lights, and all other lights are working fine. High-beam headlights work, but you have to hold the lever or else the high-beams go off. When the low-beams were working, the high-beams would engage fully and you would not have to hold the lever. l have checked the headlight fuses, and none are blown. Could this be a relay problem, or is it something else?

Thanks for your help!

could be the switch to the lights maybe a short or a loose wire,since everything else is fine pull it out and have a look be careful,,, and check the connection at the headlamp also,,,

Look in the fuse panel above the driver side wheel well under the hood.
Find the red large Head light relay (marked on the cover). Replace it and it should work fine.

This is with an assumption that both headlamp bulbs are functional and all the fuses for low/hi beam is also functional