AIR CONDITIONING SYSTEM, Diagnostic DTC:B1422/22

DTC Code DTC Name
B1422/22 Compressor Lock Sensor Circuit

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 compressor is locked, and turns the magnetic clutch off.

DTC Code DTC Detection Condition Trouble Area
B1422/22 An open or short in the compressor lock sensor circuit.

  • Cooler compressor assembly (A/C lock sensor)

  • Compressor drive belt

  • Harness or connector between cooler compressor assembly and air conditioning amplifier assembly

  • Air conditioning amplifier assembly

  • CAN communication line

WIRING DIAGRAM

A01EPXEE03

INSPECTION PROCEDURE

PROCEDURE


  1. CHECK CAN COMMUNICATION SYSTEM


    1. Use the intelligent tester to check if the CAN communication system is functioning normally.

      Result
      Result Proceed to
      CAN DTC is not output A
      CAN DTC is output (for LHD) B
      CAN DTC is output (for RHD) C

    B

    GO TO CAN COMMUNICATION SYSTEM Click here

    C

    GO TO CAN COMMUNICATION SYSTEM Click here

    A

  2. INSPECT AIR CONDITIONING AMPLIFIER ASSEMBLY


    1. A01ESF1E01

      Remove the air conditioning amplifier assembly with its connectors still connected Click here.

    2. Measure the waveform of the connector.

      Measurement Condition
      Item Content
      Terminal No. (Symbol) E35-28 (LOCK) - E35-29 (SG-5)
      Tool Setting 200 mV/DIV., 10 ms/DIV.
      Condition

      Engine running

      A/C switch on

      Blower switch lo
      OK
      Waveform is as shown in the illustration.

    NG

    INSPECT COOLER COMPRESSOR ASSEMBLY (A/C LOCK SENSOR) Click here

    OK

    REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY Click here

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


    1. A01ENUWE03

      Disconnect the C37 connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      C37-1 (SSR+) - C37-2 (SSR-) 20°C (68°F) 65 to 125 Ω

    NG

    REPLACE COOLER COMPRESSOR ASSEMBLY (A/C LOCK SENSOR) Click here

    OK

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


    1. A01EMV6E03

      Disconnect the E35 amplifier connector.

    2. Disconnect the C37 compressor connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      E35-28 (LOCK) - C37-1 (SSR+) Always Below 1 Ω
      E35-29 (SG-5) - C37-2 (SSR-)
      E35-28 (LOCK) - Body ground Always 10 kΩ or higher
      E35-29 (SG-5) - Body ground

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

    REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY Click here