B737-800
Flight Crew Multiengine; Flight Crew Air Transport Pilot (ATP); Flight Crew Instrument
Flight Crew Last 90 Days 100; Flight Crew Type 2400
Aircraft Equipment Problem Critical; Inflight Event / Encounter Other / Unknown
Flight Crew Landed in Emergency Condition; Flight Crew Returned To Departure Airport
Aircraft
On climbout at about 16;000 feet to 18;000 feet; we saw a Master Caution light with an OVHT/DET (Overheat/Detection) message on the recall. As we were evaluating where that was coming from; we had a fire bell and lights come on intermittently. We asked ATC to level off to troubleshoot. We cancelled the bell and tried to assess where the OVHT was coming from and if there was a fire. We [advised ATC] and turned back to ZZZ and continued with the ENG OVHT QRC/QRH (Engine Overheat Quick Referenece checklist/Quick Reference Handbook) as the lights and bells all ceased; there were no secondary indications of an engine fire and we thought the ENG2 OVERHEAT was illuminated. We completed the Diversion Checklist and all the other necessary checklists and landed at ZZZ.
B737-800 flight reported aircraft encountered Engine Overheat Warning inflight.