The LCD displays are stand alone, so if they have the same pinout (and many do) they power up but cannot talk to the controller.
Many controllers have a default powerup where you can run without a display. You get one PAS level and the throttle works.
So yes, the original poster can investigate that. On a five pin LCD connector, you have these five pins. They're in the same order on the flat JST plug for my LCD3 and SW900 connectors. Don't know about yours. Of you have a Julet waterproof, it's different.
-Battery Power
-Controller start
-Data out
-Data in
-Ground
When you start the display, it supplies battery power to the controller start and then uses the two data lines. To jumper a controller to run without display, you jumper the Battery power lead on the connector to the controller start lead. KT controllers come with a jumper plug to do this so you can run without the display.
Now this is battery power, 36V to 52V and if you connect it to any lead but controller start you will either fry a data lead of fry the connector ground, So you have to be sure. What's wrong with the SW900? No screen?