As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT 1011, WHILE PERFORMING OPS CHECK ON WORKCARD 3351-2991 GOT FAULT EXTERIOR LT2/EPSU 13WL AFT 4L, ESCAPE SLIDE LIGHTING. REPLACED RT AFT SLIDE PER WORKCARD# 2561-4002-RA. ALL CHECKS GOOD. RII COMPLETE. PERFORMED CIDS EPSU TEST FOR SYSTEM FAULT. (LP 8719096 - AIRCRAFT WAS GROUNDED)