What was found
(CAN) CLIMBING THROUGH 10,000 FEET, THE GPS REBOOTED & FLAGGED ON THE EFIS, SHORTLY AFTERWARDS & ELECTRICAL BURNING ODOR COULD BE DETECTED. THE AIRCRAFT RETURNED. REMOVED THE GPS FROM THE AIRCRAFT & COULD SMELL AN ELECTRICAL BURNED ODOR. NO PHYSICAL DAMAGE TO ANY CIRCUITS OR WIRING WAS FOUND INSIDE THE UNIT, BUT WHEN THE UNIT WAS HOOKED UP TO A TEST BOX, IT AGAIN EMITTED AN ELECTRICAL ODOR. A REPLACEMENT GPS WAS INSTALLED IN THE AIRCRAFT WITH NO FURTHER FAULTS. THE UNIT IS BEING SENT FOR TESTING & FAULT ISOLATION.