Last Modified: 05-13-2024 6.11:8.1.0 Doc ID: RM100000001HBSN
Model Year Start: 2020 Model: GR Corolla Prod Date Range: [01/2019 - 09/2022]
Title: HEATING / AIR CONDITIONING: AIR CONDITIONING SYSTEM (for Gasoline Model with Automatic Air Conditioning System): B1413; Evaporator Temperature Circuit or Evaporator Fin Thermistor; 2020 - 2022 MY Corolla Corolla Hatchback GR Corolla [01/2019 - 09/2022]

DTC

B1413

Evaporator Temperature Circuit or Evaporator Fin Thermistor

DESCRIPTION

The No. 1 cooler thermistor is installed to the evaporator in the air conditioner unit to detect the temperature of the cooled air that has passed through the evaporator, which is used to control the air conditioning system. It sends signals to the air conditioning amplifier assembly. The resistance of the No. 1 cooler thermistor changes in accordance with the temperature of the cooled air that has passed through the evaporator. 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 No. 1 cooler thermistor and reads voltage changes as the resistance of the No. 1 cooler thermistor changes. This sensor is used for frost prevention.

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

Memory

B1413

Evaporator Temperature Circuit or Evaporator Fin Thermistor

Open or short in evaporator temperature sensor circuit

  • No. 1 cooler thermistor
  • Air conditioning harness assembly
  • Air conditioning amplifier assembly

Memorized

(4 sec. or more)*

  • *: The air conditioning amplifier assembly stores this DTC if the malfunction has occurred for the period of time indicated in the brackets.

WIRING DIAGRAM

PROCEDURE

1.

READ VALUE USING TECHSTREAM

(a) Connect the Techstream to the DLC3.

(b) Turn the engine switch on (IG).

(c) Turn the Techstream on.

(d) Enter the following menus: Body Electrical / Air Conditioner / Data List.

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

Body Electrical > Air Conditioner > Data List

Tester Display

Measurement Item

Range

Normal Condition

Diagnostic Note

Evaporator Fin Thermistor

No. 1 cooler thermistor

Min.: -29.70°C (-21.46°F)

Max.: 59.55°C (139.19°F)

Actual evaporator temperature displayed

No. 1 cooler thermistor circuit malfunction

  • When open circuit: -29.70°C (-21.46°F)
  • When short circuit: 59.55°C (139.19°F)

Body Electrical > Air Conditioner > Data List

Tester Display

Evaporator Fin Thermistor

OK:

The display is as specified in the normal condition column.

OK

REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY

NG

2.

INSPECT NO. 1 COOLER THERMISTOR

(a) Remove the No. 1 cooler thermistor.

Click here 2020 MY Corolla Corolla Hatchback Corolla HV GR Corolla [01/2019 - 03/2019]; HEATING / AIR CONDITIONING: FRONT EVAPORATOR TEMPERATURE SENSOR: REMOVAL 2020 - 2022 MY Corolla Corolla Hatchback Corolla HV GR Corolla [03/2019 - 09/2022]; HEATING / AIR CONDITIONING: FRONT EVAPORATOR TEMPERATURE SENSOR: REMOVAL

(b) Inspect the No. 1 cooler thermistor.

Click here 2019 - 2025 MY Corolla Corolla Hatchback Corolla HV GR Corolla [06/2018 -        ]; HEATING / AIR CONDITIONING: FRONT EVAPORATOR TEMPERATURE SENSOR: INSPECTION

NG

REPLACE NO. 1 COOLER THERMISTOR 2020 MY Corolla Corolla Hatchback Corolla HV GR Corolla [01/2019 - 03/2019]; HEATING / AIR CONDITIONING: FRONT EVAPORATOR TEMPERATURE SENSOR: REMOVAL 2020 - 2022 MY Corolla Corolla Hatchback Corolla HV GR Corolla [03/2019 - 09/2022]; HEATING / AIR CONDITIONING: FRONT EVAPORATOR TEMPERATURE SENSOR: REMOVAL

OK

3.

INSPECT AIR CONDITIONING HARNESS ASSEMBLY

*a

Front view of wire harness connector

(to Air Conditioning Amplifier Assembly)

*b

Front view of wire harness connector

(to No. 1 Cooler Thermistor)

(a) Remove the air conditioning harness assembly.

Click here 2020 - 2021 MY Corolla Corolla Hatchback Corolla HV GR Corolla [01/2019 - 06/2020]; HEATING / AIR CONDITIONING: AIR CONDITIONING UNIT: DISASSEMBLY 2021 - 2022 MY Corolla Corolla Hatchback Corolla HV GR Corolla [06/2020 - 09/2022]; HEATING / AIR CONDITIONING: AIR CONDITIONING UNIT: DISASSEMBLY

(b) Measure the resistance according to the value(s) in the table below.

Standard Resistance:

Tester Connection

Condition

Specified Condition

m3-5 (SG-3) - m2-1

Always

Below 1 Ω

m3-6 (TE) - m2-2

Always

Below 1 Ω

OK

REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY

NG

REPLACE AIR CONDITIONING HARNESS ASSEMBLY 2020 - 2021 MY Corolla Corolla Hatchback Corolla HV GR Corolla [01/2019 - 06/2020]; HEATING / AIR CONDITIONING: AIR CONDITIONING UNIT: DISASSEMBLY 2021 - 2022 MY Corolla Corolla Hatchback Corolla HV GR Corolla [06/2020 - 09/2022]; HEATING / AIR CONDITIONING: AIR CONDITIONING UNIT: DISASSEMBLY