HEATING / AIR CONDITIONING: AIR CONDITIONING SYSTEM (except TMC Made, and Gasoline Model, with Automatic Air Conditioning System): No Warm Air Comes Out; 2023 MY Corolla Corolla Hatchback GR Corolla [09/2022

Last Modified: 05-13-2024	6.11:8.1.0	Doc ID: RM1000000025R2U
Model Year Start: 2023	Model: GR Corolla	Prod Date Range: [09/2022 - 11/2022]
Title: HEATING / AIR CONDITIONING: AIR CONDITIONING SYSTEM (except TMC Made, and Gasoline Model, with Automatic Air Conditioning System): No Warm Air Comes Out; 2023 MY Corolla Corolla Hatchback GR Corolla [09/2022 - 11/2022]

No Warm Air Comes Out

DESCRIPTION

If cool air blows from the registers regardless of the temperature setting of the air conditioning system, the following factors may be the cause.

Symptom	Factor
No warm air comes out (Blower control is normal) Outlet air temperature does not increase (Blower control is normal)	Engine coolant temperature (low) No. 1 air conditioning radiator damper servo sub-assembly malfunction Warm-up control Blockage in heater radiator unit sub-assembly Heater radiator unit sub-assembly malfunction Flow shutting valve malfunction*

*: w/ Flow Shutting Valve

PROCEDURE

1.	CONFIRM MODEL

(a) Choose the model to be inspected.

Result	Proceed to
w/ Flow Shutting Valve	A
w/o Flow Shutting Valve	B

GO TO STEP 3

2.	CHECK FOR DTC

(a) Connect the Techstream to the DLC3.

(b) Turn the ignition switch to ON.

(d) Enter the following menus: Powertrain / Engine / Trouble Codes.

(e) Check for DTCs.

Powertrain > Engine > Trouble Codes

OK:

SFI system DTCs are not output.

GO TO SFI SYSTEM

for M20A-FKS: Click here

for 2ZR-FAE: Click here

3.	READ VALUE USING TECHSTREAM

(a) Connect the Techstream to the DLC3.

(b) Turn the ignition switch to ON.

(d) Enter the following menus: Powertrain / Engine / Data List.

(e) Read the Data List according to the display on the Techstream.

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:

After warming up the engine, the temperature value displayed is within the range specified in the normal condition column.

GO TO COOLING SYSTEM

for M20A-FKS: Click here

for 2ZR-FAE: Click here

4.	PERFORM ACTIVE TEST USING TECHSTREAM

(a) Connect the Techstream to the DLC3.

(b) Turn the ignition switch to ON.

(d) Enter the following menus: Body Electrical / Air Conditioner / Active Test.

(e) Perform the Active Test according to the display on the Techstream.

Body Electrical > Air Conditioner > Active Test

Tester Display

Measurement Item

Control Range

Diagnostic Note

Air Mix Servo Targ Pulse(D)

No. 1 air conditioning radiator damper servo sub-assembly pulse

Min.: 128

Max.: 383

Operates between 165 and 257 pulses

Body Electrical > Air Conditioner > Active Test

Tester Display
Air Mix Servo Targ Pulse(D)

OK:

Each damper servo motor operates.

REPLACE HEATER RADIATOR UNIT SUB-ASSEMBLY

GO TO DTC TROUBLESHOOTING PROCEDURE FOR MALFUNCTIONING DAMPER SERVO MOTOR