TSB: Some 2019 ? 2020 model year Camry vehicles may exhibit a sudden drop in heater performance ~27°F (15°C) when the vehicle is driven in ambient temperatures below -4°F (-20°C) and coolant temperature is 158°F (70°C) ? 172°F (78°C). The Engine Control Module (ECM) (SAE term: Powertrain Control Module/PCM) logic has been modified to address this condition. Follow the Repair Procedure in this bulletin to address this condition.
