What was found
#2 FUEL FILTER BYPASS LIGHT ILLUMINATED AFTER ENGINE START. GROUNDED - YES. REMOVED AND REPLACED #2 ENG FUEL FILTER, DRAIN PLUG O-RING, AND RE-SAFETIED DRAIN PLUG IAW B737-800 AMM 73-11-02. ACCOMPLISHED GROUND VERIFICATION, PERFORMED IDLE ENG RUN OF #2 ENG, NO NEW FAULTS RECORDED, FILTER BYPASS LT NOT ILLUMINATED. NO DEFECTS NOTED