The paper addresses the Flow Induced Response (FIR) of a sub-surface Buoyancy Can (BC) and more particularly the yaw motions possibly due to the current vortices. 2D Computational Fluid Dynamic (CFD) simulations have been performed to analyse the turbulent flow regime over a BC. Thereafter 1 DOF and 2 DOF BC responses i.e. yaw and cross flow responses are analysed. Focusing on the yaw behaviour, a lock-in has been observed from which yaw rotations develop. The Yaw and Cross Flow (CF) appear to be coupled. As already mentioned in [8], the presence of yaw tends to weaken the CF vortex induced motions (VIM). When the 2 DOF natural periods are somehow closer, the CF response tends to be recovered.