What was found
AIRCRAFT WAS GROUNDED: ON CLIMB FROM DCA, DC FAIL LIGHT CAME ON RIGHT ADIRU SIDE. THE FIRST OFFICER SMELLED A FAINT ELECTRICAL SMELL BUT CAPTAIN DID NOT. SPEED AND MACH TRIM LIGHTS CAME ON, THEN LEFT AUTOPILOT FAILED AND THEN THE RIGHT FAILED. THE CAPTAIN MENTIONED THAT THE AUTO THROTTLE DEMANDED LOWER SPEED AT THAT TIME. AFTER LANDING IN CLT, MAINTENANCE LIGHT ON OVERHEAD ILLUMINATED ALONG WITH THE SIX PACK LIGHT CAME ON WITH LIGHT ELECTRICAL SMELL THAT COULD BE SENSED THROUGHOUT CABIN. MAINTENANCE MESSAGE 22-11333 WAS RECOVERED. FOUND STANDBY POWER CONTROL UNIT BAD AND OMITTING STRONG ELECTRICAL SMELL. REMOVED AND REPLACED STANDBY POWER CONTROL UNIT.