What was found
OKC - FLT 3554 - DURING TAKEOFF, NR 1 ENGINE FIRE WARNING CAP ILLUMINATED. NO FIRE HANDLE LIGHT, NO ENGINE FIRE DETECTED. RETURNED TO OKC. MAINTENANCE REPLACED THE W.E.U. OPS CHECK GOOD. AIRCRAFT RETURNED TO SERVICE. PART TOTAL CYCLES, 5,981.0. (X)