Vehicle Interior

Compressor Lock Sensor Circuit (B1422/22)

~2min read
SYSTEM DESCRIPTION

The ECM sends the engine speed signal to the air conditioning amplifier assembly via CAN communication.

The air conditioning amplifier assembly reads the difference between compressor speed and engine speed. When the difference becomes too large, the air conditioning amplifier assembly determines that the cooler compressor assembly is locked and turns the magnet clutch assembly off.

DTC Code

DTC Detection Condition

Trouble Area

B1422/22

Open or short in the compressor lock sensor circuit.

  • Cooler compressor assembly (A/C lock sensor)
  • Compressor drive belt
  • Harness or connector
  • Air conditioning amplifier assembly
  • CAN communication system
WIRING DIAGRAM
CAUTION / NOTICE / HINT

HINT:

As DTC B1422/22 is also output when the compressor drive belt is damaged or loose, inspect the belt before performing troubleshooting.

PROCEDURE
  1. CHECK FOR DTC (CAN COMMUNICATION SYSTEM)

(a) Use the Techstream to check if the CAN communication system is functioning normally.

Result

Result

Proceed to

CAN DTC is not output

A

CAN DTC is output

B


B

GO TO CAN COMMUNICATION SYSTEM

A
  1. INSPECT COOLER COMPRESSOR ASSEMBLY (A/C LOCK SENSOR)

(a) Remove the cooler compressor assembly (A/C lock sensor) (See page ).

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

1 - 2

20 °C

160 to 320 Ω


NG

REPLACE COOLER COMPRESSOR ASSEMBLY (A/C LOCK SENSOR)

OK
  1. CHECK HARNESS AND CONNECTOR (AIR CONDITIONING AMPLIFIER - A/C LOCK SENSOR)

(a) Disconnect the F42 amplifier connector.

(b) Disconnect the B41 sensor connector.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

F42-8 (LOCK) - B41-1

Always

Below 1 Ω

F42-13 (SG-2) - B41-2

Always

Below 1 Ω

F42-8 (LOCK) - Body ground

Always

10 kΩ or higher

F42-13 (SG-2) - Body ground

Always

10 kΩ or higher

Result

Result

Proceed to

OK (When troubleshooting according to problem symptoms table)

A

OK (When troubleshooting according to the DTC)

B

NG

C


A

PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE


B

REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY


C

REPAIR OR REPLACE HARNESS OR CONNECTOR

Test yourself

A quick Toyota 4Runner quiz: every answer comes with an explanation and a link to the manual page.