Lexus IS250 IS220d GSE20 ALE20 - AIR CONDITIONING

DESCRIPTION

WIRING DIAGRAM

INSPECTION PROCEDURE

CHECK MULTIPLEX COMMUNICATION SYSTEM

CHECK CAN COMMUNICATION SYSTEM

INSPECT ECM

INSPECT A/C COMPRESSOR (LOCK SENSOR)

CHECK WIRE HARNESS (ECM - A/C COMPRESSOR)

DTC B1422/22 Compressor Lock Sensor Circuit

DESCRIPTION

This sensor sends 1 pulse per engine revolution to the ECM.


If the ratio between engine and compressor speed deviates 20% or more compared to normal operation, the ECM turns the cooler compressor off and the indicator blinks at approximately 1 second intervals.


The ECM informs the A/C amplifier of the operation condition of the cooler compressor through multiplex communication (CAN and BEAN).

DTC No.DTC Detection ConditionTrouble Area
B1422/22 Open or short in compressor lock sensor circuit
A/C compressor
A/C compressor drive belt
A/C compressor and magnetic clutch lock sensor
Harness and connector between ECM and A/C compressor
ECM
A/C amplifier

WIRING DIAGRAM

Dtc B1422/22 Compressor Lock Sensor Circuit. AIR CONDITIONING. Lexus IS250 IS220d GSE20 ALE20

INSPECTION PROCEDURE

1.CHECK MULTIPLEX COMMUNICATION SYSTEM

Use the intelligent tester to check if the Multiplex Communication System (MPX) is functioning normally.

  • Result:
  • ResultProceed to
    MPX DTC is not outputA
    MPX DTC is outputB
B
GO TO MULTIPLEX COMMUNICATION SYSTEM
A
2.CHECK CAN COMMUNICATION SYSTEM

Use the intelligent tester to check if the CAN Communication System is functioning normally.

  • Result:
  • ResultProceed to
    CAN DTC is not outputA
    CAN DTC is outputB
B
GO TO CAN COMMUNICATION SYSTEM
A
3.INSPECT ECM
Dtc B1422/22 Compressor Lock Sensor Circuit. AIR CONDITIONING. Lexus IS250 IS220d GSE20 ALE20

Remove the ECM with its connectors still connected.

Measure the waveform of the connector.

  • Standard:
  • Tester ConnectionConditionSpecified Condition
    E3-10 (LCKI) - Body groundEngine switch on (IG)
    AUTO switch ON
    A/C switch ON
    Magnetic clutch ON    		Pulse generation
ItemContents
Tool setting200 mV/DIV., 10 ms/DIV.
Vehicle conditionEngine switch on (IG)
AUTO switch ON
A/C switch ON
Magnetic clutch ON
  • Result:
  • ResultProceed to
    NGA
    OK (When troubleshooting according to the PROBLEM SYMPTOMS TABLE)B
    OK (When troubleshooting according to the DTC)C
B
PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE
C
REPLACE ECM
A
4.INSPECT A/C COMPRESSOR (LOCK SENSOR)
Dtc B1422/22 Compressor Lock Sensor Circuit. AIR CONDITIONING. Lexus IS250 IS220d GSE20 ALE20

Disconnect the A/C compressor connector.

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

  • Standard resistance:
  • Tester ConnectionSpecified Condition
    E8-2 (SSR+) - E8-5 (SSR-)160 to 320 Ω
NG
REPLACE A/C COMPRESSOR (LOCK SENSOR)
OK
5.CHECK WIRE HARNESS (ECM - A/C COMPRESSOR)
Dtc B1422/22 Compressor Lock Sensor Circuit. AIR CONDITIONING. Lexus IS250 IS220d GSE20 ALE20

Disconnect the A/C compressor connector.

Disconnect the ECM connector.

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

  • Standard resistance:
  • Tester ConnectionConditionSpecified Condition
    E3-10 (LCKI) - E8-2 (SSR+)AlwaysBelow 1 Ω
    E3-10 (LCKI) - Body groundAlways10 kΩ or higher
    E8-5 (SSR-) - Body groundAlwaysBelow 1 Ω
NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK
REPLACE ECM
LEXUS IS250, IS220d / GSE20 ALE20
AIR CONDITIONING
Lexus IS250 IS220d GSE20 ALE20
AIR CONDITIONING SYSTEM