What was found
DURING CRUISE FLT, LT WING SPOILER NR 4 DEPLOYED INFLT. A/C ROLLED HARD LT. DISC A/P AND COUNTERED RT. SPOILERS ON BOTH WINGS DEPLOYED FOR REMAINDER OF FLT. SPOILER NR 4 PREV MEL. ON DEBRIEFING CREW, RT WING SPOILERS DEPLOYED FOR CTRL . CORRECTION ONLY. RDU - MX FOUND FAULT CODES EFCU1 M-2 3 AND 6. SWAPPED EFCU FAULT CODED EFCU POSITION 1 M-2 4 AND 7. EFCU'S RETURNED TO ORIG POS. DO THE FOLLOWING. INSPECT 4L SPOILER SURFACE AND HINGES FOR DAMAGE. CHECK WIRING FROM THE EFCU' TO THE 4L ACTUATOR AND VALVE GROUP. REPLACE 4L SPOILER VALVE GROUP. REMOVED AND REPLACED 4L SPOILER GROUP VALVE PER MM 27-64-12-4. OPS CHECKS LEAK CHECKS GOOD.