I didn't see an option. So once you pull the left trigger once, it stays locked on? Seems like I have to hold it down.
I just tested it again, and in order to stay locked on to an enemy, I have to hold the left trigger down at all times. I tried a simple tap, and it only locks on for half a second. And I don't see an option to change it.
Gaiff
maybe you're just remembering wrong. It's just a bad lock on system.
For Darksiders II on the PC, a GameFAQs message board topic titled "Can you toggle Target Lock on joystick?".
gamefaqs.gamespot.com