<p>This paper investigates the fully distributed fixed-time consensus for uncertain time-varying multi-agent systems. The fully distributed fixed-time control, both with and without unknown control directions, are proposed to fully utilize the distributed characteristics of MASs. Distinct from existing adaptive fixed-time approaches, this work uniquely integrates the challenges of time-varying parameters and unknown control directions within a unified framework combining the congelation of variables method and fixed-time consensus theory. A key contribution lies in designing control protocols and settling time estimators that require no global information, enabled by an innovative weighted Lyapunov function with carefully designed positive constants. Finally, the effectiveness of the proposed strategy is verified through two numerical simulation examples.</p>