A new localization method called LIA-SDL is introduced and applied to scan shift problems. The method combines local thermal stimulation technique with lock-in technique applied to periodical test pattern. The localization capability on soft defects is shown in comparison with SDL. Same localization results are obtained. LIA-SDL technique requires no special LSM (Laser Scan Microscope) facilities and is quite easy to handle. Limits and prospects of this new methodology are shown at several analysis examples.