We study an extension of the Higgs sector of the Standard Model (SM) with SU(2) triplet and a SM gauge singlet in the context of supersymmetry. For a Z3 symmetric superpotential where the singlet field generates the bilinear Higgs mixing term between the two Higgs doublets dynamically. Models like this, often have a very light pseudoscalar as a pseudo-Nambu Goldstone model of an extra U(1) symmetry. We investigate the possibility of such light hidden Higgs boson with the data of the discovered Higgs boson around 125 GeV. Along with the neutral sector, the charged Higgs bosons in the triplet extended case are really interesting. For instance, the triplet charged Higgs bosons give rise to new decay mode to ZW± along with an a1W± final state, due to the existence of a light pseudoscalar. These new modes can be looked for at the LHC in the search for Higgs bosons in other representations of SU(2). © The Authors, published by EDP Sciences, 2016.