Date: 201911
Local time of day: 0601-1200
Location: ZZZ.ARTCC, US
Light: Daylight
Aircraft: B737-700
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Cruise
Airspace: Class A ZZZ
ATC / advisory: Center ZZZ
Aircraft component: Aeroplane Flight Control
Component problem: Malfunctioning
Reporter organization: Air Carrier
Reporter function: Captain; Pilot Flying
Reporter qualification: Flight Crew Instrument; Flight Crew Multiengine; Flight Crew Air Transport Pilot (ATP)
Human factors: Troubleshooting; Distraction; Confusion; Situational Awareness
Second reporter function: Pilot Not Flying; First Officer
Anomaly: Aircraft Equipment Problem Less Severe; Flight Deck / Cabin / Aircraft Event Smoke / Fire / Fumes / Odor
Detector: Person Flight Crew
When detected: In-flight
Result: Aircraft Equipment Problem Dissipated; Flight Crew Diverted; Flight Crew Landed in Emergency Condition
Contributing factors: Aircraft
Primary problem: Aircraft

Narrative: We were on our first flight of the trip and in cruise at 38;000 feet. I was the Pilot Flying and the First Officer was the Pilot Monitoring. Approximately 1:30 minutes into the flight; I detected a faint odor that initially I thought might be from the air system. I mentioned this to the First Officer and then noticed smoke coming from the trip counter on my control wheel. The First Officer saw it too and we immediately put on our oxygen masks and smoke goggles and followed the QRC procedure of establishing communications. We followed the QRC which led us to the QRH. We followed the checklist for smoke; fire; fumes; and I also turned the MAIN PANEL brightness rheostat to off. At that point; the smoke had dissipated and no more smoke was emanating from the trip ID counter.We were able to determine the source; and since the smoke was no longer present; we elected to remove our oxygen masks and smoke goggles to more easily communicate and coordinate our divert. Given our location; we determined which airport was our best place to divert to. We advised with Center and were cleared direct to the airport. We were approximately 150 miles from the airport at that point. We notified Dispatch of the situation; and the First Officer informed the flight attendants of the situation. We told them to secure the cabin and also informed the passengers of the situation and our diverting to ZZZ. The landing was uneventful and no additional smoke was ever noticed. We taxied to the gate and the passengers deplaned normally. One thing a lot of us are guilty of is tapping the trip counter if the backlight is not working. This could unknowingly damage the wiring inside and cause a short which is possibly the cause of the smoke we experienced.


Second narrative: While at cruise altitude; the Captain's flight control wheel started to emit smoke and heat from the flight trip counter mounted in the upper right portion of the control wheel. We both donned our oxygen masks and goggles. The Captain then turned down the backlighting on his side via the rheostat knob just below his glare shield. The smoke appeared to dissipate. After completing the smoke fire or fumes QRC; we then completed the smoke fires or fumes QRH. As a measure of precaution in the event the smoke returned or a fire would start; we diverted to ZZZ. It was approximately 160 miles almost directly off of our nose. Given our altitude; the good weather; and knowledge of emergency services available; it was the best course of action. We discussed the situation with the flight attendants and had them clean up and take their seats. The Captain made an announcement to the passengers once we were safely on our descent. The smoke did not return and we landed uneventfully.


Synopsis: B737-700 flight crew reported advising ATC and diverting due to smoke in the cockpit during cruise.