use port 443 for VIP and pool members

BUT, when I unplug the the standby unit cable, I unable to access the active unit using port 443 , and can access port 80

Very curious. So you're saying that if you disconnect the standby unit you can no longer access the 443 VIP? Do you have multiple traffic groups enabled? And if so are you sure that the 443 VIP is alive on the active unit (vs. the standby unit)? When you disconnect the active unit, do you see a failover event in logs or any indication that the VIPs are being enabled on the standby unit?