Hot-carrier effects induced by injected carriers are reported for In1-
xGaxAsyP1-y 1.3 mum laser diodes. These effects are manifested by chan
ges of electroluminescent spectra produced by the variation of injecte
d current and heat-sink temperature. By analyzing the positions of the
peaks of envelope spectral curves and of the individual Fabry-Perot p
eaks we come to the conclusion that carrier heating and not that of th
e lattice is responsible for the observed effects.