HEATING / AIR CONDITIONING: AIR CONDITIONING SYSTEM: Cooling is Poor; 2019 - 2020 MY Camry HV [09/2018

Last Modified: 11-20-2023	6.11:8.1.0	Doc ID: RM100000001EZNA
Model Year Start: 2019	Model: Camry HV	Prod Date Range: [09/2018 - 10/2020]
Title: HEATING / AIR CONDITIONING: AIR CONDITIONING SYSTEM: Cooling is Poor; 2019 - 2020 MY Camry HV [09/2018 - 10/2020]

Cooling is Poor

DESCRIPTION

If the cooling effect of the air conditioning system is weak, the following factors may be the cause.

Symptom

Factor

Cooling effectiveness is poor
Cooling response is slow

ECO drive mode function (air flow volume is restricted due to ECO drive mode being selected)
Compressor with motor assembly malfunction
Refrigerant volume (high)
Refrigerant volume (low)
Clogged cooler condenser assembly fins
Cooling fan system malfunction
Mechanical locking of damper and damper link
Automatic light control sensor malfunction
High inlet air temperature
Harness or connector

WIRING DIAGRAM

PROCEDURE

1.	CHECK ECO MODE CONTROL OPERATION

(a) Check that ECO mode control is disabled (ECO mode indicator is not illuminated).

(b) Operate the ECO switch assembly (electric parking brake switch assembly) and check that the ECO mode indicator illuminates and the blower speed is reduced.

HINT:

When ECO mode control is operating, the air conditioning amplifier assembly controls the air conditioning system to enhance fuel efficiency. Therefore, explain to the customer that, when ECO mode control is operating, the blower speed will be reduced.

Control	Outline
Blower Control	When the air conditioning system is in AUTO mode, the blower speed will be reduced to a certain speed. Additionally, if warm-up control is operating, the blower speed will be further reduced.
Air Inlet Control	If the ambient temperature is a certain value or more, the air inlet mode will be changed to recirculation mode.

In some situations, ECO mode control may not operate even though it is enabled.

(c) Operate the ECO switch assembly (electric parking brake switch assembly) and check that the ECO mode indicator turns off and the blower speed returns to normal.

OK:

When the ECO switch assembly (electric parking brake switch assembly) is operated, ECO mode control is enabled/disabled and the blower speed is controlled.

GO TO ECO Switch Circuit

2.	PERFORM REFRIGERANT SHORTAGE CHECK

(a) Connect the Techstream to the DLC3.

(b) Turn the power switch on (IG).

(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.

REPAIR REFRIGERANT LEAK

for HFC-134a (R134a): Click here

for HFO-1234yf (R1234yf): Click here

3.	PERFORM ACTIVE TEST USING TECHSTREAM

(a) Connect the Techstream to the DLC3.

(b) Turn the power switch on (IG).

(d) Enter the following menus: Body Electrical / Air Conditioner / Active Test.

(e) Perform the Active Test according to the display on the Techstream.

Body Electrical > Air Conditioner > Active Test

Tester Display

Measurement Item

Control Range

Diagnostic Note

Air Mix Servo Targ Pulse(D)

No. 1 air conditioning radiator damper servo sub-assembly (driver side air mix) pulse

Min.: 128

Max.: 383

Operates between 165 and 257 pulses

Air Mix Servo Targ Pulse(P)

No. 1 air conditioning radiator damper servo sub-assembly (front passenger side air mix) pulse

Min.: 128

Max.: 383

Operates between 255 and 347 pulses

Body Electrical > Air Conditioner > Active Test

Tester Display
Air Mix Servo Targ Pulse(D)

Body Electrical > Air Conditioner > Active Test

Tester Display
Air Mix Servo Targ Pulse(P)

OK:

Each damper servo motor operates.

GO TO DTC TROUBLESHOOTING PROCEDURE FOR MALFUNCTIONING DAMPER SERVO MOTOR

4.	INSPECT WIRE HARNESS AND CONNECTOR (AUTOMATIC LIGHT CONTROL SENSOR - MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU))

(a) Disconnect the M1 automatic light control sensor connector.

(b) Disconnect the K52 main body ECU (multiplex network body ECU) connector.

Standard Resistance:

Tester Connection	Condition	Specified Condition
M1-1 (CLTB) - K52-23 (CLTB)	Always	Below 1 Ω
M1-2 (CLTE) - K52-25 (CLTE)	Always	Below 1 Ω
M1-4 (CLTS) - K52-24 (CLTS)	Always	Below 1 Ω
M1-1 (CLTB) or K52-23 (CLTB) - Other terminals and body ground	Always	10 kΩ or higher
M1-2 (CLTE) or K52-25 (CLTE) - Other terminals and body ground	Always	10 kΩ or higher
M1-4 (CLTS) or K52-24 (CLTS) - Other terminals and body ground	Always	10 kΩ or higher

REPAIR OR REPLACE HARNESS OR CONNECTOR

5.	INSPECT AUTOMATIC LIGHT CONTROL SENSOR

(a) Remove the automatic light control sensor.

Click here

(b) Inspect the automatic light control sensor.

Click here

INSPECT REFRIGERANT PRESSURE WITH MANIFOLD GAUGE SET

for HFC-134a (R134a): Click here

for HFO-1234yf (R1234yf): Click here

REPLACE AUTOMATIC LIGHT CONTROL SENSOR