Check out this link, it may be of some help or guidance.
VMware KB: VMware vCenter Server status alarms continually changing from green to yellow
Also, if you have external PSC's, make sure the NTP is synching properly on both the VCSA and the PSC it connects to.
If you find this or any other answer useful please mark the answer as correct or helpful
https://communities.vmware.com/people/greco827/blog
