Original post by: mayer ,
Before you condemn the drive, let's see if we can FIX IT! Hook up an external USB boot drive ( I use the Envoy enclosures with the old SSDs from upgrades - have all my system and programs upgrades on them: one boots into Sierra and one to El Capitan) (when a customer wants a SSD upgrade I pick the option of the one with the enclosure and get the drive on the cheap). So you're booted from the external. Run Disk Utilities and do a format with the "write zeros" option. If it works, it has now maps out anything it can't write to. Now do a system installation from the external.