  Kaluza-Klein (KK) parity can be violated in five-dimensional universal extra
dimensional model with boundary-localized (kinetic or mass) terms (BLTs) at the
fixed points of $S^1/Z_2$ orbifold. In this framework we study the resonant
production of Kaluza-Klein excitations of the neutral electroweak gauge bosons
at the LHC and their decay into an electron-positron pair or a muon-antimuon
pair. We use the results (first time in our knowledge) given by the LHC
experiment to constrain the mass range of the first KK-excitation of the
electroweak gauge bosons ($B^1\ \textrm{and} \ W_3^1$). It is interesting to
note that the LHC result puts an upper limit on the masses of the $n=1$
KK-leptons for positive values of BLT parameters and depending upon the mass of
$\ell^{+}\ell^{-}$ resonance.
