As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CARGO FIRE CONTROL PANEL FAILED TO TEST. CARGO FIRE EXTINGUISHING TEST FAILED FOR THE FWD AND AFT CARGO AREAS. PRESSING OF THE DISCHARGE SWITCH DID NOT SEND SQUIB FIRING VOLTAGE OUT TO THE SQUIBS. ACFT GROUNDED. REMOVED AND REPLACED THE FIRE CONTROL PANEL CARGO. INSTALLATION TESTED GOOD IAW AMM 26-00-02, AND 26-23-00. PERFORMED TASK CARD AND INSTALLATION TEST AGAIN.