Last Modified: 07-31-2024 6.11:8.1.0 Doc ID: RM100000001HCJR
Model Year Start: 2020 Model: Corolla Prod Date Range: [01/2019 - 04/2020]
Title: HEATING / AIR CONDITIONING: AIR CONDITIONING SYSTEM (for HV Model): B14A2; Driver Side Solar Sensor Short Circuit; 2020 MY Corolla Corolla HV [01/2019 - 04/2020]

DTC

B14A2

Driver Side Solar Sensor Short Circuit

DESCRIPTION

The cooler (solar sensor) thermistor is installed on the upper side of the instrument panel. It detects sunlight to control air conditioning control in AUTO mode. The output voltage from the cooler (solar sensor) thermistor varies in accordance with the amount of sunlight. When the sunlight increases, the output voltage increases. As the sunlight decreases, the output voltage decreases. The air conditioning amplifier assembly detects changes in the output voltage from the cooler (solar sensor) thermistor.

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

Memory

B14A2

Driver Side Solar Sensor Short Circuit

Short in cooler (solar sensor) thermistor circuit

  • Cooler (solar sensor) thermistor
  • Harness or connector
  • 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 power 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

Solar Sensor (D Side)

Cooler (solar sensor) thermistor

Min.: 0

Max.: 255

Cooler (solar sensor) thermistor value increase as brightness increases

Cooler (solar sensor) thermistor circuit malfunction

  • When open circuit: 0
  • When short circuit: 255

Body Electrical > Air Conditioner > Data List

Tester Display

Solar Sensor (D Side)

OK:

The display is as specified in the normal condition column.

OK

REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY

NG

2.

CHECK HARNESS AND CONNECTOR (POWER SOURCE CIRCUIT)

(a) Disconnect the m5 cooler (solar sensor) thermistor connector.

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

Standard Voltage:

Tester Connection

Condition

Specified Condition

m5-1 - m5-2

Power switch off

Below 1 V

m5-1 - m5-2

Power switch on (IG)

4.5 to 5.5 V

NG

GO TO STEP 4

OK

3.

INSPECT COOLER (SOLAR SENSOR) THERMISTOR

(a) Remove the cooler (solar sensor) thermistor.

Click here 2020 - 2025 MY Corolla Corolla Hatchback Corolla HV GR Corolla [01/2019 -        ]; HEATING / AIR CONDITIONING: SOLAR SENSOR: REMOVAL

(b) Inspect the cooler (solar sensor) thermistor.

Click here 2020 - 2025 MY Corolla Corolla Hatchback Corolla HV GR Corolla [01/2019 -        ]; HEATING / AIR CONDITIONING: SOLAR SENSOR: ON-VEHICLE INSPECTION

OK

REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY

NG

REPLACE COOLER (SOLAR SENSOR) THERMISTOR

4.

CHECK HARNESS AND CONNECTOR (COOLER (SOLAR SENSOR) THERMISTOR - AIR CONDITIONING AMPLIFIER ASSEMBLY)

(a) Disconnect the I48 air conditioning amplifier assembly connector.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

m5-1 - I48-2 (S5-1)

Always

Below 1 Ω

m5-2 - I48-9 (TS)

Always

Below 1 Ω

m5-1 or I48-2 (S5-1) - Other terminals and body ground

Always

10 kΩ or higher

m5-2 or I48-9 (TS) - Other terminals and body ground

Always

10 kΩ or higher

OK

REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR