Dtc B1244 Light Sensor Circuit Malfunction

Body Electrical. Lexus Gs430, Gs300. Uzs190 Grs190
Lighting. Lexus Gs430, Gs300. Uzs190 Grs190

DESCRIPTION

WIRING DIAGRAM

INSPECTION PROCEDURE

CHECK OPERATION (AUTOMATIC LIGHT CONTROL SENSOR)

CHECK WIRE HARNESS (MULTIPLEX NETWORK BODY ECU - AUTOMATIC LIGHT CONTROL SENSOR)

DTC B1244 Light Sensor Circuit Malfunction


DESCRIPTION

This DTC is output when a failure of the automatic light control sensor circuit is detected.

DTC No.
DTC Detection Condition
Trouble Area
B1244
  1. Malfunction of light sensor
  2. Open or short of light sensor circuit
  1. Automatic light control sensor
  2. Wire harness
  3. Multiplex network body ECU

WIRING DIAGRAM


Lexus Gs430, Gs300. Uzs190 Grs190.Lighting.Lighting System. Dtc B1244 Light Sensor Circuit Malfunction


INSPECTION PROCEDURE

1.CHECK OPERATION (AUTOMATIC LIGHT CONTROL SENSOR)

  1. Connect the intelligent tester to the DLC3.

  1. Turn the engine switch on (IG) and intelligent tester main switch ON.

  1. The value of the illumination rate should change in the following range when light contacts the light sensor or when the light sensor is covered.

    OK:
    0.008 to 0.022 seconds
    HINT:
    1. This is the time taken for the light sensor to generate one cycle of frequency according to the brightness.
    2. When not using intelligent tester.


NG
REPLACE AUTOMATIC LIGHT CONTROL SENSOR
OK


2.CHECK WIRE HARNESS (MULTIPLEX NETWORK BODY ECU - AUTOMATIC LIGHT CONTROL SENSOR)
Lexus Gs430, Gs300. Uzs190 Grs190.Lighting.Lighting System. Dtc B1244 Light Sensor Circuit Malfunction

  1. Disconnect the L67 multiplex network body ECU connector.

  1. Disconnect the M1 automatic light control sensor connector.

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

    Standard resistance:
    Tester Connection
    		Specified Condition
    L67-6 (CLTB) - M1-6 (CLTB)
    		Below 1 Ω
    L67-5 (CLTS) - M1-5 (CLTS)
    		Below 1 Ω
    L67-4 (CLTE) - M1-3 (CLTE)
    		Below 1 Ω


NG
REPAIR OR REPLACE HARNESS AND CONNECTOR
OK

REPLACE MULTIPLEX NETWORK BODY ECU