As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(B-18617) DURING DESCENT, WHEEL WELL FIRE WARNING CAME AT SPEED OF 235 KNOTS, THE LANDING GEARS WERE DOWN. THE COMPARTMENT OVERHEAT DETECTION COMPUTER SHOWED "CODE 84 - WHEEL WELL FIRE ALARM". TRIED THE WW DETECTOR REPLACEMENT IN VAIN. WITH THE DETECTOR DISCONNECTED, CODC REMAINED SHOWING "CODE 84". IT WAS CONFIRMED THAT CODC WAS FAILED. THE DEFECTED WAS LOGGED IN D/D DUE TO LACKING OF SPARE CODC.