Dtc B1655/37 Driver Side Seat Belt Buckle Switch Circuit Malfunction

Restraints. Lexus Is250, Is220D. Gse20 Ale20
Supplemental Restraint System. Lexus Is250, Is220D. Gse20 Ale20

DESCRIPTION

WIRING DIAGRAM

INSPECTION PROCEDURE

CHECK DTC

CHECK CONNECTION OF CONNECTORS

CHECK FLOOR WIRE NO. 2 (OPEN)

CHECK FLOOR WIRE NO. 2 (SHORT)

CHECK FLOOR WIRE NO. 2 (SHORT TO B+)

CHECK FLOOR WIRE NO. 2 (SHORT TO GROUND)

CHECK FRONT SEAT INNER BELT ASSEMBLY (DRIVER SIDE)

REPLACE FRONT SEAT INNER BELT ASSEMBLY (DRIVER SIDE)

CHECK CENTER AIRBAG SENSOR ASSEMBLY

DTC B1655/37 Driver Side Seat Belt Buckle Switch Circuit Malfunction


DESCRIPTION

The driver side seat belt buckle switch circuit consists of the center airbag sensor assembly and the front seat inner belt assembly (driver side).
DTC B1655/37 is recorded when a malfunction is detected in the driver side seat belt buckle switch circuit.

DTC No.
DTC Detection Condition
Trouble Area
B1655/37
  1. The center airbag sensor assembly receives a line short circuit signal, an open circuit signal, a short circuit to ground signal or a short circuit to B+ signal in the driver side seat belt buckle switch circuit for 2 seconds.
  2. Front seat inner belt assembly LH malfunction
  3. Center airbag sensor assembly malfunction
  1. Floor wire No. 2
  2. Front seat inner belt assembly (Driver side seat belt buckle switch)
  3. Center airbag sensor assembly

WIRING DIAGRAM


Lexus Is250, Is220D. Gse20 Ale20.Supplemental Restraint System.Airbag System. Dtc B1655/37 Driver Side Seat Belt Buckle Switch Circuit Malfunction


INSPECTION PROCEDURE

1.CHECK DTC


    Lexus Is250, Is220D. Gse20 Ale20.Supplemental Restraint System.Airbag System. Dtc B1655/37 Driver Side Seat Belt Buckle Switch Circuit Malfunction

  1. Turn the engine switch on (IG), and wait for at least 60 seconds.

  1. Clear the DTCs stored in the memory (Click here).

  1. Turn the engine switch off.

  1. Turn the engine switch on (IG), and wait for at least 60 seconds.

  1. Check for DTCs (Click here).

    OK:
    DTC B1655/37 is not output.
    HINT:
    Codes other than DTC B1655/37 may be output at this time, but they are not related to this check.


NG
Go to step 2
OK

USE SIMULATION METHOD TO CHECK

2.CHECK CONNECTION OF CONNECTORS

  1. Turn the engine switch off.

  1. Disconnect the negative (-) terminal cable from the battery, and wait for at least 90 seconds.

  1. Check that the connectors are properly connected to the center airbag sensor assembly and the front seat inner belt assembly (driver side).

    OK:
    The connectors are properly connected.


NG
CONNECT CONNECTORS, THEN GO TO STEP 1
OK


3.CHECK FLOOR WIRE NO. 2 (OPEN)


    Lexus Is250, Is220D. Gse20 Ale20.Supplemental Restraint System.Airbag System. Dtc B1655/37 Driver Side Seat Belt Buckle Switch Circuit Malfunction

  1. Disconnect the connectors from the center airbag sensor assembly and the front seat inner belt assembly (driver side).

  1. Using a service wire, connect Q32-11 (DBE+) and Q32-12 (DBE-) of connector "B".

    NOTICE:
    Do not forcibly insert a service wire into the terminals of the connector when connecting.

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

    Standard resistance:
    LHD:
    Tester connection
    		Condition
    		Specified condition
    Q6-1 (LBE+) - Q6-3 (LBE-)
    		Always
    		Below 1 Ω
    RHD:
    Tester connection
    		Condition
    		Specified condition
    P4-1 (RBE+) - P4-3 (RBE-)
    		Always
    		Below 1 Ω


NG
REPAIR OR REPLACE FLOOR WIRE NO. 2
OK


4.CHECK FLOOR WIRE NO. 2 (SHORT)


    Lexus Is250, Is220D. Gse20 Ale20.Supplemental Restraint System.Airbag System. Dtc B1655/37 Driver Side Seat Belt Buckle Switch Circuit Malfunction

  1. Disconnect the service wire from connector "B".

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

    Standard resistance:
    LHD:
    Tester connection
    		Condition
    		Specified condition
    Q6-1 (LBE+) - Q6-3 (LBE-)
    		Always
    		1 MΩ or higher
    RHD:
    Tester connection
    		Condition
    		Specified condition
    P4-1 (RBE+) - P4-3 (RBE-)
    		Always
    		1 MΩ or higher


NG
REPAIR OR REPLACE FLOOR WIRE NO. 2
OK


5.CHECK FLOOR WIRE NO. 2 (SHORT TO B+)


    Lexus Is250, Is220D. Gse20 Ale20.Supplemental Restraint System.Airbag System. Dtc B1655/37 Driver Side Seat Belt Buckle Switch Circuit Malfunction

  1. Connect the negative (-) terminal cable to the battery, and wait for at least 2 seconds.

  1. Turn the engine switch on (IG).

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

    Standard voltage:
    LHD:
    Tester connection
    		Condition
    		Specified condition
    Q6-1 (LBE+) - Body ground
    		Engine switch on (IG)
    		Below 1 V
    Q6-3 (LBE-) - Body ground
    		Engine switch on (IG)
    		Below 1 V
    RHD:
    Tester connection
    		Condition
    		Specified condition
    P4-1 (RBE+) - Body ground
    		Engine switch on (IG)
    		Below 1 V
    P4-3 (RBE-) - Body ground
    		Engine switch on (IG)
    		Below 1 V


NG
REPAIR OR REPLACE FLOOR WIRE NO. 2
OK


6.CHECK FLOOR WIRE NO. 2 (SHORT TO GROUND)


    Lexus Is250, Is220D. Gse20 Ale20.Supplemental Restraint System.Airbag System. Dtc B1655/37 Driver Side Seat Belt Buckle Switch Circuit Malfunction

  1. Turn the engine switch off.

  1. Disconnect the negative (-) terminal cable from the battery, and wait for at least 90 seconds.

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

    Standard resistance:
    LHD:
    Tester connection
    		Condition
    		Specified condition
    Q6-1 (LBE+) - Body ground
    		Always
    		1 MΩ or higher
    Q6-3 (LBE-) - Body ground
    		Always
    		1 MΩ or higher
    RHD:
    Tester connection
    		Condition
    		Specified condition
    P4-1 (RBE+) - Body ground
    		Always
    		1 MΩ or higher
    P4-3 (RBE-) - Body ground
    		Always
    		1 MΩ or higher


NG
REPAIR OR REPLACE FLOOR WIRE NO. 2
OK


7.CHECK FRONT SEAT INNER BELT ASSEMBLY (DRIVER SIDE)


    Lexus Is250, Is220D. Gse20 Ale20.Supplemental Restraint System.Airbag System. Dtc B1655/37 Driver Side Seat Belt Buckle Switch Circuit Malfunction

  1. Connect the connector to the center airbag sensor assembly and the front seat inner belt assembly (driver side).

  1. Connect the negative (-) terminal cable to the battery, and wait for at least 2 seconds.

  1. Turn the engine switch on (IG), and wait for at least 60 seconds.

  1. Clear the DTCs stored in the memory (Click here).

  1. Turn the engine switch off.

  1. Turn the engine switch on (IG), and wait for at least 60 seconds.

  1. Check for DTCs (Click here).

    OK:
    DTC B1655/37 is not output.
    HINT:
    Codes other than DTC B1655/37 may be output at this time, but they are not related to this check.


NG
Go to step 8
OK

USE SIMULATION METHOD TO CHECK

8.REPLACE FRONT SEAT INNER BELT ASSEMBLY (DRIVER SIDE)

  1. Turn the engine switch off.

  1. Disconnect the negative (-) terminal cable from the battery, and wait for at least 90 seconds.

  1. Replace the front seat inner belt assembly (driver side) (Click here).

    HINT:
    Perform inspection using parts from a normal vehicle if possible.

NEXT


9.CHECK CENTER AIRBAG SENSOR ASSEMBLY


    Lexus Is250, Is220D. Gse20 Ale20.Supplemental Restraint System.Airbag System. Dtc B1655/37 Driver Side Seat Belt Buckle Switch Circuit Malfunction

  1. Connect the negative (-) terminal cable to the battery, and wait for at least 2 seconds.

  1. Turn the engine switch on (IG), and wait for at least 60 seconds.

  1. Clear the DTCs stored in the memory (Click here).

  1. Turn the engine switch off.

  1. Turn the engine switch on (IG), and wait for at least 60 seconds.

  1. Check for DTCs (Click here).

    OK:
    DTC B1655/37 is not output.
    HINT:
    Codes other than DTC B1655/37 may be output at this time, but they are not related to this check.


NG
REPLACE CENTER AIRBAG SENSOR ASSEMBLY
OK

END