PTC Heater Circuit [11/2021 - 03/2023]: Description
WARNING: This page is about a different car, the 2025 Lexus NX 350h, 2024 Lexus NX 350h, 2023 Lexus NX 350h, and 2022 Lexus NX 350h. However, it is still accessible from the selected car via links, so may be relevant.
The air conditioning amplifier assembly sends operation signals to the PTC heater relays when PTC heater (quick heater assembly) operation conditions are met. Based on the signals from the air conditioning amplifier assembly, the PTC heater relays turn on, and power is supplied to the PTC heater (quick heater assembly) installed in the air conditioning radiator assembly.
HINT:
- When all drive conditions are fulfilled, 3 heater elements are driven.
- The number of heater elements driven varies depending on the engine coolant temperature.
If the heating performance is poor when it is cold, the following factors may be the cause.
| Malfunction Status | Factor |
|---|---|
| Heating performance is poor when it is cold |
|