What was found
EMERGENCY LIGHTS IN CABIN WERE FLICKERING WHILE TAXIING INTO FBO RAMP. AFTER SHUTDOWN, WE MOVED THE EMERGENCY-LIGHTS SWITCH TO ARM AND ALSO ON POSITIONS AND THE CABIN EMERGENCY LIGHTS FLICKERED IN BOTH POSITIONS. POWERED UP ACFT, MOVED EMERGENCY LIGHTS SWITCH TO ARM , EMERGENCY LIGHT CAME ON STEADY , DISCONNECTED NR 1 BATTERY & RECHECKED, LIGHTS ON STEADY RECONNECTED NR 1 & DISCONNECTED NR 2 & CHECKED AGAIN , SAME RESULTS , INSTALLED NEW BATTERIES IN NR 1 & 2 POSITIONS AND VERIFIED PROPER OPERATION, OPS CHECK GOOD IAW AMM 33-52-01.