The influence on the probe transmission (PT) and four-wave mixing (FWM) signals in a Y-type four-level system is theoretically studied, which is induced by the four kinds of dressing effect (singly-dressed and parallel-, sequential-, nested-doubly-dressed) of the coupling field. Moreover, the changed relative phase induced by the changed configuration of the coupling field also influences the signals. Numerical simulation results show that the transition between the two quantum effects of bright and dark states in PT and FWM signals can be achieved by the changed probe field detuning or the changed relative phase. Such detuning or phase controlled transition has potential applications in optical communication, quantum information processing and optoelectronic devices.