Resident Evil: Revelations 2 Message Board  

What tells you that have reached the area for the lock to unlock?

The large circle will turn yellow when you are near. When you start holding LT/RT to unlock the circle will start to shrink....make sure it always stays yellow when its shrinking; if it turns red then let go of the triggers. The last part of the unlock bar that's a deeper red color will tell you when it can be unlocked-- if its still yellow in that section of the bar then it will unlock.

Thanks for the info!