AN MD80 WAS FOUND IN NON COMPLIANCE WITH A GND CTL CIRCUIT BREAKER LEFT OPEN (PULLED) AFTER AN EXTERIOR HIGH INTENSITY LIGHT CHK.

Narrative

IN AUGUST; I WAS DISPATCHED FOR A 'POPPED' R-HAND GND CTL CIRCUIT BREAKER AND AN OVER THE WING HEATER L FAIL LIGHT ILLUMINATED. I FIRST DECIDED TO WORK THE GND CTL BREAKER DUE TO LACK OF MEL RELIEF FOR THIS DISCREPANCY. I HAD ALSO WORKED THIS SAME ACFT EARLIER THAT EVENING IN THE COCKPIT FOR A LOOSE AIR CONDITIONING KNOB. I REVIEWED THE LOGBOOK PRIOR TO CLRING THE KNOB DISCREPANCY AND DID NOT SEE ANY DISCREPANCIES FOR ANY AVIONICS OR CIRCUIT BREAKER WRITE-UPS. WHILE IN THE COCKPIT WORKING THE KNOB; A MECH CAME IN THE COCKPIT AND REACHED BEHIND THE CAPT'S SEAT. I NOTICED THE FLASHES OF THE STROBE LIGHTS IN MY PERIPHERAL VISION. I LEFT THE ACFT BEFORE THE MECH RETURNED TO THE COCKPIT. I DID NOT DIRECTLY OBSERVE WHAT THE MECH DID; BUT DURING LIGHT CHKS IT IS NORMAL FOR THE MECHS TO PULL THE GND CTL CIRCUIT BREAKERS TO ILLUMINATE THE STROBE POS LIGHTS. THE SEQUENCE OF EVENTS OF THE MECH'S LOCATION AND THE LIGHT OP A LOGICAL CONCLUSION WAS THAT THE CIRCUIT BREAKERS WERE PULLED FOR THIS LIGHT CHK. THE MECH WHO WAS REACHING BEHIND THE SEAT DID NOT INFORM ME OF ANY CIRCUIT BREAKERS FOUND OPEN. WHEN DISPATCHED LATER; THE FLT CREW RPTED THAT THE CIRCUIT BREAKER WAS FOUND OPEN ON THE CIRCUIT BREAKER PANEL DURING THEIR PREFLT. BASED ON MY OBSERVATIONS EARLIER THAT EVENING AND THE CREW'S COMMENTS; I DETERMINED THAT THE CIRCUIT BREAKER HAD BEEN LEFT OPEN DURING THE LIGHT CHK. WHEN THIS CIRCUIT BREAKER WAS RESET THE OVER THE WING HEATER FAIL LIGHT EXTINGUISHED. (NOTE: FLT CREWS OFTEN USE THE VERBIAGE 'POPPED' TO DESCRIBE CIRCUIT BREAKERS FOUND OPEN; EVEN IF THE CIRCUIT BREAKER WAS NOT HEARD; SEEN; OR SYS FAILURES INDICATE A SUDDEN LOSS OF PWR).