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Ambient Temperature Display System [12/2019 - 11/2023]: Description

The ambient temp. sensor (thermistor assembly) is installed in front of the cooler condenser assembly to detect the ambient temperature, which is used to control the air conditioning system.

The ambient temp. sensor (thermistor assembly) detects fluctuations in the ambient temperature and sends it as a signal to the air conditioning amplifier assembly.

This data is used for controlling the cabin temperature.

The resistance of the ambient temp. sensor (thermistor assembly) 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 assembly applies voltage (5 V) to the ambient temp. sensor (thermistor assembly) and detects voltage changes due to changes in the resistance of the ambient temp. sensor (thermistor assembly).

NOTE:

The ambient temp. sensor (thermistor assembly) detects the ambient temperature in its vicinity, not the ambient temperature around the vehicle.

Depending on factors such as radiant heat from the engine room and the vehicle speed, the ambient temperature detected by the ambient temp. sensor (thermistor assembly) may differ from the ambient temperature displayed on the multi-information display in the combination meter assembly.

For example:

  • When the vehicle is stopped or being driven at low speeds, the displayed ambient temperature will not be updated to a higher temperature to adjust for and minimize the influence of radiant heat from the engine room on the air conditioning system control.

    When the vehicle is not being driven at low speeds, the adjustment is performed, but updating of the displayed ambient temperature to a higher temperature is delayed.

    The displayed ambient temperature will be updated to a lower temperature regardless of the vehicle speed.

  • When the ambient temperature around the ambient temp. sensor (thermistor assembly) suddenly changes due to any reason other than radiant heat from the engine room, such as when the vehicle enters or exits a garage or tunnel, the actual ambient temperature of the vehicle and the displayed ambient temperature may differ or changing of the displayed value may be delayed.
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