What was found
WINDSHEAR/GPWS INOPERATIVE. LIGHT ILLUMINATED DURING TAKE-OFF ROLL. RTO CONDUCTED WINDSHEAR IN AREA. A/C WEIGHT 154,200 LBS., OAT 19 DEGREES C., PA 280, & BRAKE ENERGY ZONE CAUTION. TRANSFERRED TO DMI 14774 MEL 34-29 CAT. (A) PLACARD INSTALLED. INSPECTED BRAKES IAW MM, NO DEFECTS NOTED. SUSPECT GPWS COMPUTER. NO STOCK. SWAPPED GPWS COMPUTER & RADIO ALTIMETER, NO HELP. ORIGINAL GPWS & RADIO ALTIMETER BOXES REINSTALLED. REMOVED INSTRUMENT PANEL ON F/O'S FORWARD LT SIDE. FOUND GPWS TEST/INHIBIT SWITCH CORRODED. PARTS ON ORDER. REINSTALLED & PERFORMED PITOT-STATIC LEAK CK IAW MM, NO LEAKS NOTED. REPLACED F/O'S GPWS KORRY LIGHT, GPWS NOW OPS CKS GOOD PER MM. THIS CLEARS DMI 14774.