Dtc B1422/22 Compressor Lock Sensor Circuit

Heater & Air Conditioning System. Lexus Gs430, Gs300. Uzs190 Grs190
Air Conditioning. Lexus Gs430, Gs300. Uzs190 Grs190

DESCRIPTION

WIRING DIAGRAM

INSPECTION PROCEDURE

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 Condition
Trouble Area
B1422/22
Open or short in compressor lock sensor circuit
  1. A/C compressor
  2. A/C compressor drive belt
  3. A/C compressor and magnetic clutch lock sensor
  4. Harness and connector between ECM and A/C compressor
  5. ECM
  6. A/C amplifier

WIRING DIAGRAM


Lexus Gs430, Gs300. Uzs190 Grs190.Air Conditioning.Air Conditioning System. Dtc B1422/22 Compressor Lock Sensor Circuit


INSPECTION PROCEDURE

1.INSPECT ECM
Lexus Gs430, Gs300. Uzs190 Grs190.Air Conditioning.Air Conditioning System. Dtc B1422/22 Compressor Lock Sensor Circuit

  1. Remove the ECM with its connectors still connected.

  1. Measure the waveform of the connector.

    Standard voltage:
    Tester Connection
    		Condition
    		Specified Condition
    E8-10 (LCKI) - Body ground
    		Engine switch on (IG)
    AUTO switch ON
    A/C switch ON
    Magnetic clutch ON
    		Pulse generation
Item
Contents
Tool setting
200 mV / DIV, 10 ms / DIV
Vehicle condition
Engine switch on (IG)
AUTO switch ON
A/C switch ON
Magnetic clutch ON

Result:
NG
A
OK (Checking from the PROBLEM SYMPTOMS TABLE)
B
OK (Checking from the DTC)
C


B
PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE

C
REPLACE ECM
A


2.INSPECT A/C COMPRESSOR (LOCK SENSOR)
Lexus Gs430, Gs300. Uzs190 Grs190.Air Conditioning.Air Conditioning System. Dtc B1422/22 Compressor Lock Sensor Circuit

  1. Disconnect the E46 A/C compressor connector.

  1. Measure the resistance of the sensor.

    Standard resistance:
    Tester Connection
    		Specified Condition
    2 (SSR+) - 5 (SSR-)
    		400 Ω


NG
REPLACE A/C COMPRESSOR (LOCK SENSOR)
OK


3.CHECK WIRE HARNESS (ECM - A/C COMPRESSOR)
Lexus Gs430, Gs300. Uzs190 Grs190.Air Conditioning.Air Conditioning System. Dtc B1422/22 Compressor Lock Sensor Circuit

  1. Disconnect the E46 A/C compressor connector.

  1. Disconnect the E8 ECM connector.

  1. Measure the resistance of the wire harness side connectors.

    Standard resistance:
    Tester Connection
    		Condition
    		Specified Condition
    E8-10 (LCKI) - E46-2 (SSR+)
    		Always
    		Below 1 Ω
    E46-5 (SSR-) - Body ground
    		Always
    		Below 1 Ω


NG
REPAIR OR REPLACE HARNESS AND CONNECTOR
OK

REPLACE ECM