its calling to execute scripts to make it tow.go to the global folder in one of the pak files,and open the tow_dm.scr,and youll see the script.
and also check out the MP_Berlin_TOW.scr
if u dont know didly about scripting it might look like jibberish to you
it's telling the bomb on an mg42 to know when it's placed and to take care of itself so it blows up, th other one you'll have to look at the script to find out