As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
#2 ENGINE FIRE LIGHT DOES NOT ILLUMINATE ON TEST. GROUNDED - YES. REPLACED ENGINE CORE DETECTION HARNESS MW0326 WITH SERVICABLE UNIT. ENG FIRE DETECTION OPS CHECKS OK. REF B737-800 AMM 26-11-02, 26-11-00, AND ASA MAINTENANCE PROGRAM 05-07-01, TABLE 3, ITEM 7.