Abstract: When using Si solar cells, there can be some difficulties due to shunts which lead to short circuits that can cause a malfunction and the melting of the electrical wires with possible inflammation. Breakdown sites in multicrystalline Si solar cells have been studied by the reverse-bias electroluminescence by the electron (EBIC) and Laser Beam Induced Current (LBIC) and energy dispersive X-ray spectroscopy methods. In the breakdown sites revealed by EL at small reverse bias (~5 V) the enhanced aluminum and oxygen concentration is revealed. Such breakdowns can be located inside the depletion region because they are not revealed by the EBIC or LBIC methods. Breakdowns revealed by EL at larger bias well correlate with extended defects in the EBIC and LBIC images.