Vibrationally resolved threshold photoelectrons in coincidence (TPEsCO) spectra of the X(3)Sigma (-) and a(1)Delta states of HCl2+ and DCl2+ are compared with ab initio simulations. The four resonances observed in the TPEsCO spectra of both the X(3)Sigma (-) and a(1)Delta states of HCl2+ are assigned as three quasi-bound vibrational levels and one continuum resonance with an energy greater than the potential barrier maximum. The four clearly identified resonances observed in Cl2+ the TPEsCO spectra of both the X(3)Sigma (-) and a(1)Delta states of DCl2+ are assigned as quasi-bound vibrational levels.