  We investigate the implications of a minimal $SU(2)$ gauge symmetry extension
of the standard model at the LHC. To achieve the spontaneous symmetry breaking,
a heavy Higgs doublet of the $SU(2)$ is introduced. To obtain an anomaly free
model and the decays of new charged gauge bosons, we include a vector-like
quark doublet. We also employ a real scalar boson to dictate the heavy Higgs
production via the gluon-gluon fusion processes. It is found that the new gauge
coupling and the masses of new gauge bosons can be strictly bounded by the
electroweak $\rho$-parameter and dilepton resonance experiments at the LHC. It
is found that due to the new charged gauge boson enhancement, the cross
sections for a heavy scalar boson to diphoton channel measured by ATLAS and CMS
can be easily satisfied when the values of Yukawa couplings are properly taken.
Furthermore, by adopting event simulation, we find that the significance of
$pp\to (\gamma \gamma)_H+{\rm jet}$, where the diphoton is from the heavy Higgs
decay, can be over $4\sigma$ when the luminosity is above 60 fb$^{-1}$.
