As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING PRE-FLIGHT CHECKS ON THE GROUND WITH THE APU RUNNING, A "FIRE BOTTLE 2 LO PRESS" INDICATION FOLLOWED BY A "FIRE BOTTLE 1 LO PRESS" INDICATION APPEARED IN THE FLIGHT DECK. NO FIRE OCCURRED ON THE AIRCRAFT. IT WAS FOUND THAT THE AFT CLAMP ON THE LH FLOW CONTROL VALVE HAD COME LOOSE AND CAUSED A BLEED AIR LEAK. THE LEAK WAS DIRECTED AT BOTH FIRE BOTTLES AND CAUSED THEM TO THERMALLY DISCHARGE ON THE GROUND.