As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
BAT CHARGER APU APU BATTERY CHARGER FAILURE. STATUS MSG01-ACTIVE CRUISE MODE DEPENDENT; APU BATTERY IS WEAK. DB- ELMS P310 ELECTRONICS UNIT MSG02- ACTIVE CRUISE MODE DEPENDENT; APU BATTERY IS WEAK. MSG-2413047 ACTIVE ER MODE MSG-2413047 ACTIVE ER MODE. STS MSG BAT CHARGER APU SHOWING. DEFERRED PER MEL 2431D. REPLACED APU CHARGER IAW MM. VOLTS AND AMPS NORMAL.