General question PS4 slim BD drive/ WLOD

I have a question.
I have several PS4 slim at home and wanted to try to repair them. A question has arisen that I unfortunately can’t test because I don’t know if something else is defective.
Would a PS4 slim (SAF 4 and SAF 5) start (output something to the TV) even if the BD drive is not connected or is there only a WLOD?
Could someone test this and let me know!