As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT WAS GROUNDED: PILOT REPORTS DURING PUSHBACK SMELLED ELECTRICAL ODOR. SHORTLY AFTERWARD HEARD LOUD GRINDING NOISE. ODOR DETECTED IN FLIGHT DECK. MAINTENANCE REMOVED AND REPLACED EXTRACT AND BLOWER FAN IAW AMM 21-26-51. OPS CHECK GOOD, OK FOR SERVICE.