Last Modified: 08-21-2023 6.11:8.1.0 Doc ID: RM100000001RUIH
Model Year Start: 2021 Model: Avalon Prod Date Range: [08/2020 -           ]
Title: HEATING / AIR CONDITIONING: AIR CONDITIONING SYSTEM (for Gasoline Model): B1451; Compressor Solenoid Circuit; 2021 - 2022 MY Avalon [08/2020 -        ]

DTC

B1451

Compressor Solenoid Circuit

DESCRIPTION

The compressor assembly with pulley*1 or cooler compressor assembly*2 receives refrigerant compression demand signals from the air conditioning amplifier assembly.

Based on this signal, the compressor assembly with pulley*1 or cooler compressor assembly*2 changes the amount of compressor output.

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

Memory

B1451

Compressor Solenoid Circuit

Open or short in compressor solenoid circuit
  • Compressor assembly with pulley*1
  • Cooler compressor assembly*2
  • Harness or connector
  • Air conditioning amplifier assembly

-
  • *1: for A25A-FKS
  • *2: for 2GR-FKS

WIRING DIAGRAM

for A25A-FKS:
for 2GR-FKS:

PROCEDURE

1.

CONFIRM MODEL

Result

Proceed to

for A25A-FKS

A

for 2GR-FKS

B
B

GO TO STEP 4

A

2.

INSPECT AIR CONDITIONING AMPLIFIER ASSEMBLY

*a

Front view of wire harness connector

(to Compressor Assembly with Pulley)

(a) Disconnect the C111 compressor assembly with pulley connector.

(b) Connect an oscilloscope to terminal C111-2 (SOL+) and body ground and check the waveform.

Item

Content

Tool Setting

5 V/DIV., 500 μs./DIV.

Condition
  • Engine running
  • Blower switch: LO
  • A/C switch: On

OK:

Waveform is similar to that shown in the illustration.

OK

REPLACE COMPRESSOR ASSEMBLY WITH PULLEY 2019 - 2021 MY Avalon HV [04/2018 - 08/2021]; HEATING / AIR CONDITIONING: COMPRESSOR (for A25A-FXS): REMOVAL 2022 MY Avalon HV [08/2021 -        ]; HEATING / AIR CONDITIONING: COMPRESSOR (for A25A-FXS): REMOVAL

NG

3.

CHECK HARNESS AND CONNECTOR (COMPRESSOR ASSEMBLY WITH PULLEY - AIR CONDITIONING AMPLIFIER ASSEMBLY)

(a) Disconnect the G35 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

C111-2 (SOL+) - G35-3 (SOL+)

Always

Below 1 Ω

C111-2 (SOL+) or G35-3 (SOL+) - Other terminals and body ground

Always

10 kΩ or higher
OK

REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

4.

INSPECT AIR CONDITIONING AMPLIFIER ASSEMBLY

*a

Front view of wire harness connector

(to Cooler Compressor Assembly)

(a) Disconnect the C59 cooler compressor assembly connector.

(b) Connect an oscilloscope to terminal C59-2 (SOL+) and body ground and check the waveform.

Item

Content

Tool Setting

5 V/DIV., 500 μs./DIV.

Condition
  • Engine running
  • Blower switch: LO
  • A/C switch: On

OK:

Waveform is similar to that shown in the illustration.

OK

REPLACE COOLER COMPRESSOR ASSEMBLY

NG

5.

CHECK HARNESS AND CONNECTOR (COOLER COMPRESSOR ASSEMBLY - AIR CONDITIONING AMPLIFIER ASSEMBLY)

(a) Disconnect the G35 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

C59-2 (SOL+) - G35-3 (SOL+)

Always

Below 1 Ω

C59-2 (SOL+) or G35-3 (SOL+) - Other terminals and body ground

Always

10 kΩ or higher
OK

REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR