just passed my mod 2 found that a lot of the questions was based around c+e and not c as I’ve only just passed my cat c I thought I would let some new drivers in on abit of info cos I did not find much todo with this module,theorytest4all can help but try and learn about certain aspects of an artic lorrie locking devices and how the lorrie works helps I gained abit of my knowledge from working in tuffnells so guess I was lucky with this anyway hope this helps. 
Yeah it seems fairly straight forward, I’m doing mine now in a few weeks! When are you doing your mod 4?