HEATING / AIR CONDITIONING: AIR CONDITIONING SYSTEM (for Gasoline Model with Automatic Air Conditioning System): Recirculated/Fresh Air Modes Switch without User Input; 2023 - 2025 MY Corolla Corolla Hatchback GR Corolla [11/2022

Last Modified: 05-13-2024	6.11:8.1.0	Doc ID: RM1000000028C4G
Model Year Start: 2023	Model: GR Corolla	Prod Date Range: [11/2022 - ]
Title: HEATING / AIR CONDITIONING: AIR CONDITIONING SYSTEM (for Gasoline Model with Automatic Air Conditioning System): Recirculated/Fresh Air Modes Switch without User Input; 2023 - 2025 MY Corolla Corolla Hatchback GR Corolla [11/2022 - ]

Recirculated/Fresh Air Modes Switch without User Input

DESCRIPTION

If recirculation/fresh mode changes unintentionally and without permission, the following causes are possible.

Symptom	Factor
Recirculation/fresh mode changes without permission Recirculation/fresh mode light blinks	Customize setting Change in ambient air temperature Decrease in refrigerant pressure Air conditioning pressure sensor circuit malfunction Engine coolant temperature (high)

PROCEDURE

1.	READ VALUE USING GTS

(a) Read the Data List according to the display on the GTS.

Body Electrical > Air Conditioner > Data List

Tester Display	Measurement Item	Range	Normal Condition	Diagnostic Note
Efficient Ventilation Mode	Function to automatically change ambient air induction and room circulation is set.	OFF / ON	Customized value displayed	-

Body Electrical > Air Conditioner > Data List

Tester Display
Efficient Ventilation Mode

Result	Proceed to
Efficient Ventilation Mode is set to "OFF"	A
Efficient Ventilation Mode is set to "ON"	B

CUSTOMIZE SETTING (Efficient Ventilation Mode to "OFF")

2.	READ VALUE USING GTS

(a) Read the Data List according to the display on the GTS.

Body Electrical > Air Conditioner > Data List

Tester Display	Measurement Item	Range	Normal Condition	Diagnostic Note
Ambient Temperature Sensor	Ambient temp. sensor (thermistor assembly)	-327.68 to 327.67°C	Actual ambient temperature displayed	Ambient temp. sensor (thermistor assembly) circuit malfunction

Body Electrical > Air Conditioner > Data List

Tester Display
Ambient Temperature Sensor

OK:

The value of the display does not change frequently.

GO TO OTHER DIAGNOSIS PROCEDURE (Ambient Temperature Display System)

3.	READ VALUE USING GTS (COOLANT TEMPERATURE)

(a) Read the Data List according to the display on the GTS.

Powertrain > Engine > Data List

Tester Display

Measurement Item

Range

Normal Condition

Diagnostic Note

Coolant Temperature

Engine coolant temperature

Min.: -40°C (-40°F)

Max.: 140°C (284°F)

75 to 100°C (167 to 212°F): After warming up

This is the engine coolant temperature.

HINT:

After warming up the engine, the engine coolant temperature will be 75 to 100°C (167 to 212°F).
After a long soak, the engine coolant temperature, intake air temperature and ambient air temperature will be approximately equal.
If the value is -40°C (-40°F), or higher than 135°C (275°F), the sensor circuit is open or shorted.
Check if the engine overheats if the value indicated is higher than 135°C (275°F).

Powertrain > Engine > Data List

Tester Display
Coolant Temperature

OK:

The value of the display does not change frequently.

GO TO COOLING SYSTEM

for G16E-GTS: Click here

for M20A-FKS: Click here

4.	CHECK REFRIGERANT PRESSURE

(a) Install a manifold gauge set.

Click here

(b) Prepare the vehicle according to the table below.

Measurement Condition:

Item	Condition
Doors	Fully open
A/C Switch	On
Recirculation/fresh Control Switch	Recirculation
Set Temperature	MAX COLD
Blower Speed	HI
Air Conditioning Air Inlet Temperature	25 to 35°C (77 to 95°F)

Body Electrical > Air Conditioner > Data List

Tester Display	Measurement Item	Range	Normal Condition	Diagnostic Note
Regulator Pressure Sensor	Air conditioning pressure sensor	-32.768 to 32.767 MPaG	Actual refrigerant pressure displayed	Refrigerant line (gas leak etc.) Air conditioning pressure sensor circuit malfunction

Body Electrical > Air Conditioner > Data List

Tester Display
Regulator Pressure Sensor

OK:

The values displayed in the Data List and on the manifold gauge match.

INSPECT REFRIGERANT PRESSURE WITH MANIFOLD GAUGE SET

REPLACE AIR CONDITIONING PRESSURE SENSOR