ccsvchost is the service which takes care of the scan in 12.x now, you wont be able to stop this service as it will be grayed out in services.msc
if you want to stop the client service, you can do that from run cmd , smc -stop / start
all available cmds here
https://support.symantec.com/en_US/article.TECH103048.html
if you want to disable symantec, do the opposite of this
https://support.symantec.com/en_US/article.TECH102822.html
Symantec Endpoint Protection Enterprise Edition 12.1 client services are grayed out in services.msc
http://www.symantec.com/docs/TECH174068