What was found
DURING FLIGHT NR 3666, EMERGENCY BATTERY LIGHT ILLUMINATED OUTBOUND. AIR RETURN TO DTW. MAINTENANCE REPLACED EMERGENCY POWER SUPPLY P/N 501-1228-04, S/N ON 4684, S/N OFF 1606 IAW MAL TASK CARD 243502. OPS CHECK GOOD.
As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
DURING FLIGHT NR 3666, EMERGENCY BATTERY LIGHT ILLUMINATED OUTBOUND. AIR RETURN TO DTW. MAINTENANCE REPLACED EMERGENCY POWER SUPPLY P/N 501-1228-04, S/N ON 4684, S/N OFF 1606 IAW MAL TASK CARD 243502. OPS CHECK GOOD.