What was found
INFLIGHT HYDRAULIC PUMP CYCLED ON/OFF, CAPT EHSI AND EADI WENT BLANK, EMERGENCY POWER LIGHT CYCLED ON AND OFF AND THE LT GENERATOR VOLTS DROP TO OR BELOW 20 VOLTS. 15 MINUTES LATER EVERYTHING RETURNED TO NORMAL. MAINTENANCE REPLACED LT AND RT BATTERY P/N 4078-7, RT S/N OFF G012620, S/N ON F00544, LT S/N OFF R3068, S/N ON 095372. GROUND RAN A/C ACTIVATED HYD PUMP. NO DISCREPANCIES NOTED ALL CHECKS GOOD.