As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
LAX FLIGHT NR 2388: WHILE STARTING NR 2 ENGINE WITH APU DURING PUSHBACK, THE STANDBY BATTERY LOAD SHOWED +1.99 LOAD AND WOULD NOT COME DOWN AFTER START. MAINTENANCE REPLACED STANDBY BATTERY SHUNT PER Q400 TASK 24-31-51-000-801 AND 24-31-51-400-801. LOAD CHECKS GOOD. AIRCRAFT RETURNED TO SERVICE.