As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AFTER STARTING ENGINE NR 1, DRIVE LIGHT ILLUMINATED AND GENERATOR WOULD NOT COME ON LINE. ACFT GROUNDED. PERFORMED TEST IAW MM 24-11-00-700-802. NR 1 DRIVE LIGHT ILLUMINATED WITH ENGINE AT IDLE AND NR 1 IDG SHOWED NO VOLTS OR FREQS. REPLACED NR 1 IDG IAW AMM TASK 24-11-11-400-801, OPS TEST GOOD.