Last Modified: 08-21-2023 6.11:8.1.0 Doc ID: RM100000001A3OF
Model Year Start: 2019 Model: Avalon HV Prod Date Range: [04/2018 -           ]
Title: HEATING / AIR CONDITIONING: AIR CONDITIONING SYSTEM (for HV Model): A/C Switch Indicator does not Turn On; 2019 - 2022 MY Avalon HV [04/2018 -        ]

A/C Switch Indicator does not Turn On

DESCRIPTION

If none of the switch indicators on the air conditioning control panel (radio and display receiver assembly) illuminate, the following factors may be the cause.

Symptom

Factor

A/C switch indicator does not illuminate
  • Air conditioning amplifier assembly malfunction
  • Air conditioning control panel (radio and display receiver assembly) malfunction
  • A/C switch malfunction
  • A/C switch indicator malfunction (including when indicator turned off without switch operation)
  • Servo motor initialization (incomplete)
  • Mechanical locking of damper and damper link
  • Refrigerant pressure is extremely low
  • Low detected ambient temperature (including thermistor assembly malfunction)

PROCEDURE

1.

CHECK MALFUNCTION STATUS

(a) Check the malfunction status of switch indicators on the air conditioning control panel (radio and display receiver assembly).

Result

Proceed to

Indicators are not always illuminated

A

Indicators are not illuminated only immediately after starting the engine

B
B

GO TO INITIALIZATION

A

2.

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

Ambient Temp Sensor

Thermistor assembly

Min.: -23.30°C (-9.94°F)

Max.: 65.95°C (150.71°F)

Actual ambient temperature displayed

Thermistor assembly circuit malfunction

  • When open circuit: -23.30°C (-9.94°F)
  • When short circuit: 65.95°C (150.71°F)

Body Electrical > Air Conditioner > Data List

Tester Display

Ambient Temp Sensor

OK:

The value displayed is 0°C (32°F) or higher.

OK

INSPECT REFRIGERANT PRESSURE WITH MANIFOLD GAUGE SET

NG

GO TO OTHER DIAGNOSIS PROCEDURE (Ambient Temperature Display System)