As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
RED MAIN DECK CARGO FIRE WARNING WITH ASSOCIATED LIGHTS AND MASTER CAUTION INTERMITTENTLY EVERY 5 MINS.MTX GROUNDED A/C .MTX REMOVED AND REPLACED PRINTED CIRCUIT CARD IN P54 M2026 IAW B767 AMM 26-10-01 & OPS CHECKS GOOD & NO FAULTS NOTED AT THIS TIME. AND RETURNED A/C TO SERVICE.