Flight Crew Air Transport Pilot (ATP); Flight Crew Instrument; Flight Crew Multiengine
Situational Awareness
Aircraft Equipment Problem Less Severe; Deviation / Discrepancy - Procedural Published Material / Policy; Flight Deck / Cabin / Aircraft Event Smoke / Fire / Fumes / Odor
Air Traffic Control Provided Assistance; Flight Crew Diverted; Flight Crew Landed in Emergency Condition
Aircraft
My flight diverted to ZZZZ due to persistent unidentifiable odor in the cockpit extending into most of the business class cabin. [Advised ATC]; decided not to delay landing; and landed overweight. Landing was uneventful. ZZZZ emergency crews inspected aircraft; and determined it was safe to taxi to gate. Cockpit access system electronics overheated. Maintenance found system circuit breaker open.
B777-200 Captain reported a divert due to smoke in the cockpit and business class cabin area.