No Heating at All [12/2023 - ]: Description

WARNING: This page is about a different car, the 2024 Lexus TX 550h+. However, it is still accessible from the selected car via links, so may be relevant.

If cool air blows from the registers regardless of the temperature setting of the air conditioning system, the following factors may be the cause.

Symptom	Factor
No warm air comes out (Blower control is normal) Outlet air temperature does not increase (Blower control is normal)	Engine coolant temperature (low) Air mix damper and link operation (jamming) Warm-up control Blockage in heater radiator unit sub-assembly Heater radiator unit sub-assembly malfunction High voltage electric heater (electric heater sub-assembly) malfunction Heating three-way valve (heater water valve assembly) malfunction Electric water pump (rear heater pump assembly) malfunction