The role of the whisker-related primary somatosensory cortex (wS1) in perceptual decisions remains a topic of ongoing debate. While previous research has linked wS1 to stimulus detection, discrimination, and the coordination of whisker movements during active touch and associative learning in simple stimulus detection tasks, its contribution to behavior becomes crucial as cognitive load and perceptual demands escalate. The gap-crossing task has thus emerged as a model for studying wS1 functions, requiring freely-moving mice to actively employ their whiskers to locate a target platform after a gap and execute an appropriate action to cross the gap for a reward. Previous studies on wS1 ablation in the gap-crossing task yielded mixed evidences, often due to the complete removal of cortical tissue compromising vital cortico-cortical projections, and the lack of ethological tools to accurately classify behavior. To overcome these limitations, we combine precise exocytotoxic lesions and partial sensory deprivation with advanced computer vision and time series clustering algorithms to track, segment and classify mouse gap-crossing behavior. Expert mice with intact whiskers exhibited minimal performance deficits after wS1 lesions, fully recovering task skills after a single session. Similarly, naïve mice with intact whiskers and wS1 lesions could learn the task. Interestingly, both groups showed significant impairment in recovering learned task skills when subjected to partial sensory deprivation. Our findings underscore the importance of considering cortical remapping, precise lesion targeting and ethological classification to fully understand wS1 function in the context of freely moving self-initiated behavior.