What was found
ON DESCENT BURNING SMELL IN COCKPIT AT 121,000', DISSIPATED BY 17,000'. MORE OF A PLASTIC BURNING SMELL. NO HOTSPOTS NOTED BY HAND IN COCKPIT. NO OVERHEATED WINDOWS. CAPTAIN MAP LIGHT WAS LEFT ON & WAS HOT BUT DID NOT SMELL. DISSIPATED SMELL NEVER RETURNED. R & R CONTROL CABIN TEMP SENSOR IAW SIP.