What was found
AIRCRAFT ON A TEST FLIGHT AND DURING AN RPM DECAY TEST, THE LT ENGINE POWER LEVER WAS REDUCED BELOW 1400 HP. THE RPM THEN STARTED TO DECAY BELOW PRESCRIBED LIMITS. DUE TO THIS, THE CREW ELECTED TO SHUT DOWN THE ENGINE. THE PROBLEM ONLY OCCURRED BELOW 1400 HP. THE CREW CARRIED OUT SEVERAL RESTARTS, WHICH DID NOT RESOLVE THE OCCURRENCE AND ELECTED TO LAND WITH THE ENGINE SHUT DOWN. TROUBLE SHOOTING IDENTIFIED AN INCORRECT WIRING CONFIGURATION, WHICH WAS CORRECTED.