HEATING / AIR CONDITIONING: AIR CONDITIONING SYSTEM (for Gasoline Model with Automatic Air Conditioning System): A/C Switch Indicator does not Turn On; 2026 MY GR Corolla Corolla Corolla Hatchback [08/2025

Last Modified: 06-05-2026	6.11:8.1.0	Doc ID: RM0000003TPCQ7C
Model Year Start: 2026	Model: GR Corolla	Prod Date Range: [08/2025 - ]
Title: HEATING / AIR CONDITIONING: AIR CONDITIONING SYSTEM (for Gasoline Model with Automatic Air Conditioning System): A/C Switch Indicator does not Turn On; 2026 MY GR Corolla Corolla Corolla Hatchback [08/2025 - ]

A/C Switch Indicator does not Turn On

DESCRIPTION

If none of the switch indicators on the air conditioning control assembly illuminate, the following factors may be the cause.

Malfunction Status	Factor
A/C switch indicator does not illuminate	Air conditioning amplifier assembly malfunction Air conditioning control assembly malfunction Servo motor initialization (incomplete) Mechanical locking of damper and damper link Refrigerant pressure is extremely low Low detected ambient temperature (including thermistor assembly malfunction)

1.	CHECK MALFUNCTION STATUS

(a) Check the malfunction status of switch indicators on the air conditioning control assembly.

Result	Proceed to
A/C switch indicators are not always illuminated	A
A/C switch indicators are not illuminated only immediately after starting the hybrid control system	B

2.	READ VALUE USING GTS

(a) Read the Data List according to the display on the GTS.

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

OK:

The display is as specified in the normal condition column (0°C (32°F) or higher).

INSPECT REFRIGERANT PRESSURE WITH MANIFOLD GAUGE SET

for HFC-134a(R134a): Click here

for HFO-1234yf(R1234yf): Click here