DTC B1411: Room Temperature Sensor Circuit [10/2018 - ]: Description
WARNING: This page does not describe the selected car, but rather 6 other vehicles, including the 2024 Lexus UX 250h, 2023 Lexus UX 250h, 2022 Lexus UX 250h, 2021 Lexus UX 250h, and 2020 Lexus UX 250h. However, it is still accessible from the selected car via links, so may be relevant.
The cooler (room temp. sensor) thermistor is installed in the instrument panel to detect the cabin temperature, which is used to control the air conditioning system. The resistance of the cooler (room temp. sensor) thermistor changes in accordance with the cabin temperature. As the temperature decreases, the resistance increases. As the temperature increases, the resistance decreases.
The air conditioning amplifier assembly applies voltage (5 V) to the cooler (room temp. sensor) thermistor and reads voltage changes due to changes in the resistance of the cooler (room temp. sensor) thermistor.
| DTC No. | Detection Item | DTC Detection Condition | Trouble Area | Memory |
|---|---|---|---|---|
| B1411 | Room Temperature Sensor Circuit |
|
|
Memorized (4 sec. or more)* |
- *: The air conditioning amplifier assembly stores this DTC if the malfunction has occurred for the period of time indicated in the brackets.
DTC Detection Conditions
| Vehicle Condition | |||
|---|---|---|---|
| Pattern 1 | Pattern 2 | ||
| Diagnosis Condition | Power switch on (IG) | ◦ | ◦ |
| Malfunction Status | Open in room temperature sensor circuit | ◦ | - |
| Short in room temperature sensor circuit | - | ◦ | |
| Detection Time | 4 sec. or more | 4 sec. or more | |
| Number of Trips | 1 trip | 1 trip | |
HINT:
- DTC will be output when conditions for either of the patterns in the table above are met.
- If the cabin temperature is approximately -18.6°C (-1.48°F) or lower, DTC B1411 may be stored even though the system is normal.