What was found
AIRCRAFT NOT GROUNDED: MAINTENANCE REPORTS DURING CIDS 1 SYSTEM TEST, EPSU TEST, MSG BAT/EPSU(11WL) EXT L FAULTED, FAILED. REPLACED EPSU BATTERY 11WL, OPS CHECK NORMAL. CIDS 1 SYSTEM TEST EPSU TEST CHECKS GOOD, MSG CLEARED IAW AMM 33-51-38.