Can anyone help me doing the following actions FCA 737?From the MAIN PREFLIGHT: Oxygen test (how to do?)BEFORE TAXI: confirm Gen voltage ( How to confirm it?) EAI/WAI button (where is this)?? Also there is no taxi lights turning on in the before taxi FLOWS also CHECKLIST???From sounds checklist I cant find and do the following:Oxygen ( how to test?)Presuruzation mode selctor?This part becames to puzzling for me..