Please check this article from Mick2009:
SAV for Linux Scanning Best Practices: A (Somewhat) Illustrated Guide
https://www-secure.symantec.com/connect/articles/sav-linux-scanning-best-practices-somewhat-illustrated-guide
How to check if AutoProtect is enabled?
Here is the command line to run from /opt/Symantec/symantec_antivirus
sudo ./sav info -a
to enable it:
sudo ./sav autoprotect -e
to disable it:
sudo ./sav autoprotect -d