The Boeing 747-400 aircraft, registered 9M-MPE, was conducting an international scheduled passenger flight from Kuala Lumpur, Malaysia to Melbourne. During cruise at flight level 390, the cabin crew reported an electrical smell near doors 1, 2 and 4. The flight crew immediately completed the "Smoke, Fumes, Fire, Electrical" checklist actions and the smell dissipated. Approximately one hour later, a similar smell became evident in the cockpit and the flight crew elected to divert the aircraft to Adelaide as a precaution.
After landing at Adelaide, an engineering inspection of the aircraft was conducted by the operator's engineers. This inspection revealed that the air conditioning right overhead recirculation fan had seized and the left overhead recirculation fan was causing the circuit breaker to trip. Both overhead recirculation fans were isolated electrically in accordance with the requirements of the aircraft's Minimum Equipment List and the aircraft was returned to service.