Photovoltaic modules suffer from degradations under operating conditions, and equally during transportation, installation and maintenance. Among common degradation modes, cracks represent an important alteration factor for photovoltaic panels. Actually, their connection to the efficiency loss of a photovoltaic module has not been well established yet. In the present study, the impact of the depth of an open crack within a heterojunction solar cell was studied using a finite element model. Steady-state simulations of the PN junction were carried out for a depth ranging from 0 to 5 µm. A linear decrease is obtained for the short-circuit current and, an important drop of the open-circuit voltage is found between 0 and 0.25 µm depth. The efficiency is significantly reduced, from 19.97% to 12.94%, with a crack depth of 5 µm.