What was found
PHNY TO PHNL FLT 663, CREW NOTICED A STANDBY POWER INOP CASS MESSAGE ILLUMINATED. GETTING READY TO COMPLETE STANDBY POWER INOP CHKLIST, NOTICED THE STANDBY POWER INOP CASS MESSAGE DISAPPEARED & GENERATOR OFF CASS MESSAGE ILLUMINATED. CREW SAW A DISCHARGE WITH GEN AMPS. WAS ABOUT TO PERFORM GEN OFF CHKLIST, GEN OFF CAS MESSAGE EXTING & WITH A POSITIVE CHARGE ON GEN. STANDBY POWER INOP CAS MESSAGE ILLUMINATED AGAIN. COMPLETED STANDBY POWER INOP CHKLIST & CASS MESSAGE REMAINED. CREW ASSESSED SITUATION, DECIDED THE SAFEST COURSE WAS TO DIVERT TO NEAREST AIRPORT, PHMK. ADVISED ATC OF OUR DECISION & LANDED SAFELY IN MOLOKAI. CREW TAXIED PLANE TO RAMP & SHUT ENG DOWN.