  We study Fe$_{1+y}$Te$_{0.6}$Se$_{0.4}$ multi-band superconductor with
$T_c=14$K by polarization-resolved Raman spectroscopy. Deep in the
superconducting state, we detect pair-breaking excitation at 45cm$^{-1}$
($2\Delta=5.6$meV) in the $XY$($B_{2g}$) scattering geometry, consistent with
twice of the superconducting gap energy (3 meV) revealed by ARPES on the
hole-like Fermi pocket with $d_{xz}/d_{yz}$ character. We analyze the
superconductivity induced phonon self-energy effects for the $B_{1g}$(Fe)
phonon and estimate the electron-phonon coupling constant $\lambda^\Gamma
\approx 0.026$, which is insufficient to explain superconductivity with
$T_c=14$K.
