The elastic single charge exchange scattering ^<13>C(π^+,π^0)^<13>N at the 3 3 resonance region is analyzed in the coupled channel eikonal type approximation. The asymptoticπ^++^<13>C and theπ^0+^<13>N channels are coupled in the nuclear interior, where the total isospin I=3/2 specifies the eigen channel. The last scattering of the pion with a nucleon can beπ^0→π^0 elastic orπ^+→π^0 charge exchange. Two corresponding amplitudes appear and the interference is constructive above the pion kinetic energy T_π>150MeV. We remark that the pair distribution is not properly treated in the DWIA calculation for this scattering.