Last Modified: 08-21-2023 6.11:8.1.0 Doc ID: RM1000000019XOD
Model Year Start: 2019 Model: Avalon Prod Date Range: [04/2018 -           ]
Title: HEATING / AIR CONDITIONING: AIR CONDITIONING SYSTEM (for Gasoline Model): Air Conditioning Compressor Magnetic Clutch Circuit; 2019 - 2022 MY Avalon [04/2018 -        ]

Air Conditioning Compressor Magnetic Clutch Circuit

DESCRIPTION

When the engine is running, If refrigerant pressure does not decrease when the A/C switch is turned off, the following factors may be the cause.

Symptom

Factor
  • Cooler compressor assembly does not stop operating
  • Refrigerant pressure does not decrease when A/C switch is turned off
  • Short to +B in air conditioning amplifier assembly circuit malfunction
  • MG CLT relay malfunction
  • Magnet clutch 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.

INSPECT MG CLT RELAY

(a) Inspect the MG CLT relay.

Click here 2019 MY Avalon Avalon HV [04/2018 - 08/2019]; HEATING / AIR CONDITIONING: RELAY: ON-VEHICLE INSPECTION 2020 - 2022 MY Avalon Avalon HV [08/2019 -        ]; HEATING / AIR CONDITIONING: RELAY: ON-VEHICLE INSPECTION

NG

REPLACE MG CLT RELAY
OK

2.

CHECK HARNESS AND CONNECTOR (MG CLT RELAY - POWER SOURCE)

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

Standard Voltage:

Tester Connection

Condition

Specified Condition

3 (MG CLT relay) - Body ground

Always

11 to 14 V

1 (MG CLT relay) - Body ground

Engine switch off

Below 1 V

1 (MG CLT relay) - Body ground

Engine switch on (IG)

11 to 14 V
NG

REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

3.

CHECK HARNESS AND CONNECTOR (MG CLT RELAY - AIR CONDITIONING AMPLIFIER ASSEMBLY)

(a) Disconnect the G36 air conditioning amplifier assembly connector.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

2 (MG CLT relay) - G36-9 (MGC)

Always

Below 1 Ω

2 (MG CLT relay) or G36-9 (MGC) - Other terminals and body ground

Always

10 kΩ or higher
NG

REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

4.

CHECK HARNESS AND CONNECTOR (MG CLT RELAY - MAGNET CLUTCH ASSEMBLY AND BODY GROUND)

(a) Disconnect the C60 magnet clutch assembly connector.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

5 (MG CLT relay) - C60-3 (MG+)

Always

Below 1 Ω

5 (MG CLT relay) or C60-3 (MG+) - Other terminals and body ground

Always

10 kΩ or higher
NG

REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

5.

CHECK HARNESS AND CONNECTOR (MAGNET CLUTCH ASSEMBLY - BODY GROUND)

(a) Install the MG CLT relay.

(b) Connect the C60 compressor assembly with magnetic clutch connector.

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

Standard Voltage:

Tester Connection

Condition

Specified Condition

C60-3 (MG+) - Body ground

Engine running

(A/C switch: Off)

Below 1 V
OK

REPLACE MAGNET CLUTCH ASSEMBLY

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR