DTC B1412/12 Ambient Temperature Sensor Circuit: Description

WARNING: This page is about a different car, the 2007 Toyota RAV4. However, it is still accessible from the selected car via links, so may be relevant.

The ambient temperature sensor is installed in the front part of the condenser to detect the ambient temperature and control the air conditioner. The sensor is connected to the combination meter and detects fluctuations in the ambient temperature. This data is used for controlling the room temperature. The sensor sends a signal to the air conditioning amplifier via the combination meter. The resistance of the ambient temperature sensor changes in accordance with the ambient temperature. As the temperature decreases, the resistance increases. As the temperature increases, the resistance decreases.

The air conditioning amplifier applies a voltage (5 V) to the ambient temperature sensor and reads voltage changes as changes in the resistance of the ambient temperature sensor. The combination meter sends the read signal to the air conditioning amplifier via CAN communication.

DTC DETECTION CONDITION AND TROUBLE AREA

DTC No.	DTC Detection Conditions	Trouble Areas
B1412/12	Open or short in ambient temperature sensor circuit	Ambient temperature sensor Harness and connector between ambient temperature sensor and combination meter assembly Combination meter Air conditioning amplifier CAN communication line