What was found
DURING ROUTINE MX, AN ODOR IN THE FORWARD CABIN, FLIGHT DECK, AND OUTSIDE THE ACFT. UPON FURTHER INSPECTION FOUND THE FLY BY WIRE BACK-UP BATTERY SMOKING AND THE OVER HEAT LED LIGHT ON. THE BATTERY WAS REPLACED IAW AMM, OPS CHECK GOOD AND NOW OK FOR SERVICE. NO OTHER DEFECTS WERE FOUND.