ASC

ASC stands for "Ammonia Slip Catalyst." In diesel vehicles equipped with an SCR (Selective Catalytic Reduction) system, ammonia is injected (usually in the form of a urea solution) to reduce nitrogen oxides (NOₓ) emissions. However, due to various reaction conditions, some ammonia may not fully react and can slip through the system. The ASC is designed to catalytically oxidize this excess ammonia into harmless nitrogen and water, further reducing harmful emissions from the exhaust.