Last Modified: 05-13-2024 6.11:8.1.0 Doc ID: RM1000000026ZAH
Model Year Start: 2023 Model: GR Corolla Prod Date Range: [09/2022 - 11/2022]
Title: HEATING / AIR CONDITIONING: AIR CONDITIONING SYSTEM (for TMC Made, and Gasoline Model, with Manual Air Conditioning System for Electrical Control Type): Recirculated/Fresh Air Modes Switch without User Input; 2023 MY Corolla Corolla Hatchback GR Corolla [09/2022 - 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
B

CUSTOMIZE SETTING (Efficient Ventilation Mode to "OFF")
A

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.

NG

GO TO OTHER DIAGNOSIS PROCEDURE (Ambient Temperature Display System)

OK

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.

NG

GO TO COOLING SYSTEM

OK

4.

CHECK REFRIGERANT PRESSURE

(a) Install a manifold gauge set.

Click here 2020 - 2025 MY Corolla Corolla Hatchback Corolla HV GR Corolla [01/2019 -        ]; HEATING / AIR CONDITIONING: REFRIGERANT (for HFO-1234yf(R1234yf)): ON-VEHICLE INSPECTION

(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)

(c) Compare the values displayed in the Data List and on the manifold gauge.

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.

OK

INSPECT REFRIGERANT PRESSURE WITH MANIFOLD GAUGE SET

NG

REPLACE AIR CONDITIONING PRESSURE SENSOR