As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
During test of Emergency lighting System JC #335003, Maintenance found several lights Inop under no power conditions. Found Power supply 20LN PN 3301-51 SN/2192 at fault. Removed and replaced Power Supply PN 3301-51, SN ON 1370, SN OFF 2192. .