The testicles can be moved passively but not actively. Active movements are possible only via reflex contraction of the cremaster muscle located in the funiculus spermaticus. Contraction of musculus cremastericus elevates the testicles and brings them closely to the body. Contraction of that muscle is provoked by cold weather/environment or by skin scratching on the inner side of the leg (s.c. cremastern reflex). You can consult a urologist about a possible erection problem and seek advice.