Last Modified: 07-31-2024 6.11:8.1.0 Doc ID: RM1000000026Z4J
Model Year Start: 2023 Model: Corolla Prod Date Range: [09/2022 -           ]
Title: HEATING / AIR CONDITIONING: AIR CONDITIONING SYSTEM (for HV Model): Operation not Accepted Even If Air Conditioning Switch is Operated; 2023 - 2025 MY Corolla Corolla HV [09/2022 -        ]

Operation not Accepted Even If Air Conditioning Switch is Operated

DESCRIPTION

If the air conditioning system cannot be operated using the air conditioning control assembly, the following factors may be the cause.

Symptom

Factor

Air conditioning system cannot be operated using air conditioning control assembly

  • (With the exception of the switch indicators, no inputs are reflected when other switches operated)
  • LIN communication malfunction between air conditioning amplifier assembly and air conditioning control assembly
  • Short to +B or ground in air conditioning amplifier assembly circuit
  • Air conditioning amplifier assembly malfunction
  • Air conditioning control assembly malfunction
  • Harness or connector

WIRING DIAGRAM

CAUTION / NOTICE / HINT

NOTICE:

Inspect the fuses for circuits related to this system before performing the following procedure.

PROCEDURE

1.

CHECK FOR DTC

(a) Clear the DTC.

Body Electrical > Air Conditioner > Clear DTCs

(b) Check for DTCs.

Body Electrical > Air Conditioner > Trouble Codes

Result

Proceed to

B14B287 is not output

A

B14B287 is output

B
B

GO TO DTC B14B287

A

2.

CHECK HARNESS AND CONNECTOR (AIR CONDITIONING AMPLIFIER ASSEMBLY - AUXILIARY BATTERY)

(a) Disconnect the I49 air conditioning amplifier assembly connector.

*a

Front view of wire harness connector

(to Air Conditioning Amplifier Assembly)

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

Standard Voltage:

Tester Connection

Condition

Specified Condition

I49-5 (B) - Body ground

Ignition switch off

11 to 14 V

I49-6 (IG+) - Body ground

Ignition switch ON

11 to 14 V

Ignition switch off

Below 1 V
NG

REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

3.

CHECK HARNESS AND CONNECTOR (AIR CONDITIONING AMPLIFIER ASSEMBLY - BODY GROUND)

(a) Disconnect the I49 air conditioning amplifier assembly connector.

*a

Front view of wire harness connector

(to Air Conditioning Amplifier Assembly)

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

I49-17 (GND) - Body ground

Always

Below 1 Ω
OK

REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY 2023 MY Corolla Corolla Hatchback Corolla HV GR Corolla [09/2022 - 11/2022]; HEATING / AIR CONDITIONING: AIR CONDITIONING AMPLIFIER: REMOVAL 2023 - 2025 MY Corolla Corolla Hatchback Corolla HV GR Corolla [11/2022 -        ]; HEATING / AIR CONDITIONING: AIR CONDITIONING AMPLIFIER: REMOVAL

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR