Last Modified: 08-21-2023 6.11:8.1.0 Doc ID: RM100000001A3OG
Model Year Start: 2019 Model: Avalon HV Prod Date Range: [04/2018 -           ]
Title: HEATING / AIR CONDITIONING: AIR CONDITIONING SYSTEM (for HV Model): Front Window Fogging; 2019 - 2022 MY Avalon HV [04/2018 -        ]

Front Window Fogging

DESCRIPTION

If the windshield frequently fogs up even though the air conditioning system is operating, the following factors may be the cause.

Symptom

Factor

Windshield frequently fogs up

  • Compressor with motor assembly malfunction
  • Refrigerant volume (low)
  • Cooler expansion valve (opened excessively)
  • No. 1 air conditioning radiator damper servo sub-assembly malfunction
  • Mechanical locking of damper and damper link

PROCEDURE

1.

PERFORM REFRIGERANT SHORTAGE CHECK

(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 / Utility / Refrigerant Gas Volume Check.

Body Electrical > Air Conditioner > Utility

Tester Display

Refrigerant Gas Volume Check

(e) Check that the following conditions are met and perform the refrigerant shortage check according to the display on the Techstream.

Measurement Condition:

Item

Condition

A/C switch

On

Ambient temperature*

0 to 49°C (32 to 120°F)

Blower speed

HI

*: If the ambient temperature is not within the range shown, do not perform this check.

Result

Amount of Refrigerant

Refrigerant correct

Correct

Refrigerant shortage

Insufficient

OK:

"Refrigerant correct" is displayed on the Techstream.

NG

CHARGE SYSTEM WITH REFRIGERANT

OK

2.

CHECK OPERATION

(a) Press the front defroster switch on the air conditioning control panel (radio and display receiver assembly).

OK:

The air outlet mode changes to DEF mode.

OK

INSPECT REFRIGERANT PRESSURE WITH MANIFOLD GAUGE SET

NG

GO TO DTC B1443