What was found
AT FL 390, BELLY DOOR OPEN WARNING LIGHT ILLUMINATED. PERFORMED ABNORMAL PROCEDURE. PRESSURIZATION NORMAL. CONTINUED NORMAL OPERATION. ASSIGNED DMI 13146 MEL 52-1 COMPLIED WITH SPECIAL PROCEDURES. REF DMI 13146 BELLY DOOR OPEN WARNING LIGHT ILLUMINATED (A-PIT). RII REQUIRED. REMOVED AND REPLACED BELLY DOOR OPEN WARNING SWITCH. OPS CHECKED GOOD IAW M/M 52-70-0. MAINTENANCE CONTROL NOTIFIED. THIS CLEARS DMI 13146.