NHTSA Complaint #11446233 — 2018 MAZDA CX-5

This is more of a general notice to fellow Mazda CX-5 drivers with the issue described below: Our car is a 2018 CX-5 with 25K miles. The check engine light came on upon entering the highway at the beginning of the day. Subsequently, stopping by an AutoZone to diagnose it revealed a malfunctioning thermostat. Only then did I realize the car took a long time to reach the operating temperature (for the blue indicator light to go away), and engine temperature would generally stay around 165 and hit 210 only after a very long time of driving, while idling or in traffic. However, our internal heater performance never had any issues while being kept at 75 and blowing mild to moderately. Upon taking the car to our Mazda dealership and requesting a diagnostic service, did we learn it was a malfunctioning coolant control valve that there is a technical service bulletin (# 01-011/21) for such a thing, and covered under our CPO powertrain warranty for replacement.