What was found
(CAN) DURING OVERNIGHT CHECK IN THE HANGER, AVIONICS FOUND THE A/P STAB TRIM MOTOR C/B WAS POPPED. TRIED A RESET BUT NO JOY AND C/B FELT ODD. TURNED A/C POWER OFF AND C/B WOULD NOT RESET. C/B REPLACED. C/B RESET BUT POPPED A FRACTION OF A SECOND LATER. AVIONIC WENT TO STAB BAY TO REMOVE PLUG FROM MOTOR AND NOTED BAY HAD SMOKE. INVESTIGATION REVEALED THAT MOTOR CONNECTOR PLUG AND APPROX. 3 INCHES OF ASSOCIATED WIRING SHOWED SIGNS OF OVERHEATING, ARCING, ETC. THE PLUG, SOME WIRING AND THE MOTOR WERE REPLACED.