What was found
ON PRE-FLIGHT CARGO DISCH LIGHT ON. GROUNDED - YES. ATTEMPTED TO APPLY MEL 26-19I, MEL MTX PROCEDURE DOES NOT PASS. DISCONNECTED THE NR 1 CARGO FIRE BOTTLE PRESSURE SWITCH CPD12792, DISCHARGE LIGHT EXTINGUISHES. FOUND PIN NR 3 IN THE FIRE BOTTLE SHORTED DIRECTLY TO CAGE GROUND W/O EVEN GOING TO PIN NR 2. REPLACED THE NR 1 CARGO FIRE BOTTLE IAW T/C 78226001. COMPLETED CARGO FIRE CTL PANEL INSTALLATION IAW AMM 26-00-02-400-801 STEP 3F TO END. OPS TEST GOOD FOR THE FIRE BOTTLE AND THE CONTROL PANEL. CARGO DISCHARGE LIGHT REMAINS EXTINGUISHED.