What was found
DURING CLIMBOUT THROUGH FL210 THE F/O'S SIDE WINDOW OVERHEAT LIGHT ILLUMINATED, WE EXECUTED THE OVERHEAT (WINDOW) CHECKLIST WHICH HAS US RESET THE SWITCH. AFTER RESETTING, THE LIGHT REMAINED EXTINGUISHED UNTIL 2000' WHEN THE WINDOW ANNUNCIATOR ILLUMINATED AGAIN ON DESCENT. GROUNDED - YES. REMOVED W0210-1001-20 FROM TERMINAL #2 AND INSTALLED IT TO TERMINAL #1 ON TB5014 PER B737-900 WDM 30-41-11 AND B737-900 AMM SUBTASK 30-41-21-210-001. REPLACED FO'S SLIDER WINDOW PER AMM 56-12-11-400-801. ADJ AND OPS TEST GOOD.