Dtc B1653/35 Seat Position Airbag Sensor Circuit Malfunction

Vehicle Interior. Yaris. Ncp93, 131
Supplemental Restraint Systems. Yaris. Ncp93, 131

DESCRIPTION

WIRING DIAGRAM

INSPECTION PROCEDURE

CHECK CONNECTORS

CHECK SEAT POSITION AIRBAG SENSOR CIRCUIT (OPEN)

CHECK SEAT POSITION AIRBAG SENSOR CIRCUIT (SHORT)

CHECK SEAT POSITION AIRBAG SENSOR CIRCUIT (SHORT TO B+)

CHECK SEAT POSITION AIRBAG SENSOR CIRCUIT (SHORT TO GROUND)

CHECK SEAT POSITION AIRBAG SENSOR

REPLACE SEAT POSITION AIRBAG SENSOR

CHECK DTC

CHECK FLOOR WIRE (OPEN)

CHECK FLOOR WIRE (SHORT)

CHECK FLOOR WIRE (SHORT TO B+)

CHECK FLOOR WIRE (SHORT TO GROUND)

DTC B1653/35 Seat Position Airbag Sensor Circuit Malfunction


DESCRIPTION

The seat position airbag sensor circuit consists of the airbag sensor assembly, front seat inner belt assembly LH and seat position airbag sensor.
DTC B1653/35 is stored when a malfunction is detected in the seat position airbag sensor circuit.

DTC No.
DTC Detection Condition
Trouble Area
B1653/35
  1. The 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 seat position airbag sensor circuit.
  2. Front seat inner belt assembly LH malfunction
  3. Seat position airbag sensor malfunction
  4. Airbag sensor assembly malfunction
  1. Floor wire
  2. Front seat inner belt assembly LH
  3. Seat position airbag sensor
  4. Airbag sensor assembly

WIRING DIAGRAM


Yaris. Ncp93, 131.Supplemental Restraint Systems.Airbag System (For Sedan). Dtc B1653/35 Seat Position Airbag Sensor Circuit Malfunction


INSPECTION PROCEDURE

1.CHECK CONNECTORS

  1. Turn the ignition switch off.

  1. Disconnect the cable from the negative (-) battery terminal.

    CAUTION:
    Wait at least 90 seconds after disconnecting the cable from the negative (-) battery terminal to disable the SRS system.

  1. Check that the connectors are properly connected to the airbag sensor assembly, front seat inner belt assembly LH and seat position airbag sensor.

    OK:
    The connectors are properly connected.
    HINT:
    If the connectors are not connected securely, reconnect the connectors and proceed to the next inspection.

  1. Disconnect the connectors from the airbag sensor assembly, front seat inner belt assembly LH and seat position airbag sensor.

  1. Check that the terminals of the connectors are not damaged.

    OK:
    The terminals are not deformed or damaged.


NG
REPLACE WIRE HARNESS
OK


2.CHECK SEAT POSITION AIRBAG SENSOR CIRCUIT (OPEN)


  1. Connect the connectors to the front seat inner belt assembly LH and floor wire.


    Yaris. Ncp93, 131.Supplemental Restraint Systems.Airbag System (For Sedan). Dtc B1653/35 Seat Position Airbag Sensor Circuit Malfunction


Text in Illustration
*1
Seat Position Airbag Sensor
*2
Airbag Sensor Assembly
*3
Connector B
*4
Connector E
*5
Service Wire
-
-
*a
Front view of wire harness connector
(to Airbag Sensor Assembly)
*b
Front view of wire harness connector
(to Seat Position Airbag Sensor)

  1. Using the service wire, connect terminals 9 (LSP+) and 17 (LSP-) of connector B.

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

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

    Standard Resistance:
    Tester Connection
    		Condition
    		Specified Condition
    2 (LSP+) - 1 (LSP-)
    		Always
    		Below 1 Ω


NG
Go to step 9
OK


3.CHECK SEAT POSITION AIRBAG SENSOR CIRCUIT (SHORT)


    Yaris. Ncp93, 131.Supplemental Restraint Systems.Airbag System (For Sedan). Dtc B1653/35 Seat Position Airbag Sensor 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:
    Tester Connection
    		Condition
    		Specified Condition
    2 (LSP+) - 1 (LSP-)
    		Always
    		1 MΩ or higher
    Text in Illustration
    *1
    		Seat Position Airbag Sensor
    *2
    		Airbag Sensor Assembly
    *3
    		Connector E
    *a
    		Front view of wire harness connector
    (to Seat Position Airbag Sensor)


NG
Go to step 10
OK


4.CHECK SEAT POSITION AIRBAG SENSOR CIRCUIT (SHORT TO B+)


    Yaris. Ncp93, 131.Supplemental Restraint Systems.Airbag System (For Sedan). Dtc B1653/35 Seat Position Airbag Sensor Circuit Malfunction

  1. Connect the cable to the negative (-) battery terminal.

  1. Turn the ignition switch to ON.

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

    Standard Voltage:
    Tester Connection
    		Switch Condition
    		Specified Condition
    2 (LSP+) - Body ground
    		Ignition switch ON
    		Below 1 V
    1 (LSP-) - Body ground
    		Ignition switch ON
    		Below 1 V
    Text in Illustration
    *1
    		Seat Position Airbag Sensor
    *2
    		Airbag Sensor Assembly
    *3
    		Connector E
    *a
    		Front view of wire harness connector
    (to Seat Position Airbag Sensor)


NG
Go to step 11
OK


5.CHECK SEAT POSITION AIRBAG SENSOR CIRCUIT (SHORT TO GROUND)


    Yaris. Ncp93, 131.Supplemental Restraint Systems.Airbag System (For Sedan). Dtc B1653/35 Seat Position Airbag Sensor Circuit Malfunction

  1. Turn the ignition switch off.

  1. Disconnect the cable from the negative (-) battery terminal.

    CAUTION:
    Wait at least 90 seconds after disconnecting the cable from the negative (-) battery terminal to disable the SRS system.

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

    Standard Resistance:
    Tester Connection
    		Condition
    		Specified Condition
    2 (LSP+) - Body ground
    		Always
    		1 MΩ or higher
    1 (LSP-) - Body ground
    		Always
    		1 MΩ or higher
    Text in Illustration
    *1
    		Seat Position Airbag Sensor
    *2
    		Airbag Sensor Assembly
    *3
    		Connector E
    *a
    		Front view of wire harness connector
    (to Seat Position Airbag Sensor)


NG
Go to step 12
OK


6.CHECK SEAT POSITION AIRBAG SENSOR

  1. Connect the connectors to the airbag sensor assembly and seat position airbag sensor.

  1. Connect the cable to the negative (-) battery terminal.

  1. Turn the ignition switch to ON, and wait for at least 60 seconds.

  1. Clear the DTCs stored in memory (YARIS_NCP93 RM000000XFE0EEX.html).

  1. Turn the ignition switch off.

  1. Turn the ignition switch to ON, and wait for at least 60 seconds.

  1. Check for DTCs (YARIS_NCP93 RM000000XFE0EEX.html).

    OK:
    DTC B1653/35 is not output.
    HINT:
    Codes other than DTC B1653/35 may be output at this time, but they are not related to this check.


NG
Go to step 7
OK

USE SIMULATION METHOD TO CHECK (YARIS_NCP93 RM00000135202EX.html)

7.REPLACE SEAT POSITION AIRBAG SENSOR

  1. Turn the ignition switch off.

  1. Disconnect the cable from the negative (-) battery terminal.

    CAUTION:
    Wait at least 90 seconds after disconnecting the cable from the negative (-) battery terminal to disable the SRS system.

  1. Replace the seat position airbag sensor with a known good one (YARIS_NCP93 RM000000UWJ05HX.html).

    HINT:
    Perform the following inspection using known good parts from another vehicle if possible.

NEXT


8.CHECK DTC

  1. Connect the cable to the negative (-) battery terminal.

  1. Turn the ignition switch to ON, and wait for at least 60 seconds.

  1. Clear the DTCs stored in memory (YARIS_NCP93 RM000000XFE0EEX.html).

  1. Turn the ignition switch off.

  1. Turn the ignition switch to ON, and wait for at least 60 seconds.

  1. Check for DTCs (YARIS_NCP93 RM000000XFE0EEX.html).

    OK:
    DTC B1653/35 is not output.
    HINT:
    Codes other than DTC B1653/35 may be output at this time, but they are not related to this check.


NG
REPLACE AIRBAG SENSOR ASSEMBLY (YARIS_NCP93 RM000000V6U02AX.html)
OK

END (SEAT POSITION SENSOR WAS DEFECTIVE)

9.CHECK FLOOR WIRE (OPEN)


  1. Disconnect the floor wire from the front seat inner belt assembly LH.


    Yaris. Ncp93, 131.Supplemental Restraint Systems.Airbag System (For Sedan). Dtc B1653/35 Seat Position Airbag Sensor Circuit Malfunction


    Text in Illustration
    *1
    		Seat Position Airbag Sensor
    		*2
    		Airbag Sensor Assembly
    *3
    		Front Seat Inner Belt Assembly LH
    		*4
    		Floor Wire
    *5
    		Connector B
    		*6
    		Connector C
    *7
    		Service Wire
    		-
    		-
    *a
    		Front view of wire harness connector
    (to Airbag Sensor Assembly)
    		*b
    		Front view of wire harness connector
    (to Front Seat Inner Belt Assembly LH)
    HINT:
    The service wire has already been inserted into connector B.

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

    Standard Resistance:
    Tester Connection
    		Condition
    		Specified Condition
    J67-4 (LSP+) - J67-3 (LSP-)
    		Always
    		Below 1 Ω


NG
REPLACE FLOOR WIRE
OK

REPLACE FRONT SEAT INNER BELT ASSEMBLY LH (YARIS_NCP93 RM000000SY000SX.html)

10.CHECK FLOOR WIRE (SHORT)
Yaris. Ncp93, 131.Supplemental Restraint Systems.Airbag System (For Sedan). Dtc B1653/35 Seat Position Airbag Sensor Circuit Malfunction

  1. Disconnect the floor wire from the front seat inner belt assembly LH.

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

    Standard Resistance:
    Tester Connection
    		Condition
    		Specified Condition
    J67-4 (LSP+) - J67-3 (LSP-)
    		Always
    		1 MΩ or higher
    Text in Illustration
    *1
    		Seat Position Airbag Sensor
    *2
    		Airbag Sensor Assembly
    *3
    		Front Seat Inner Belt Assembly LH
    *4
    		Floor Wire
    *5
    		Connector C
    *a
    		Front view of wire harness connector
    (to Front Seat Inner Belt Assembly LH)


NG
REPLACE FLOOR WIRE
OK

REPLACE FRONT SEAT INNER BELT ASSEMBLY LH (YARIS_NCP93 RM000000SY000SX.html)

11.CHECK FLOOR WIRE (SHORT TO B+)


    Yaris. Ncp93, 131.Supplemental Restraint Systems.Airbag System (For Sedan). Dtc B1653/35 Seat Position Airbag Sensor Circuit Malfunction

  1. Turn the ignition switch off.

  1. Disconnect the cable from the negative (-) battery terminal.

    CAUTION:
    Wait at least 90 seconds after disconnecting the cable from the negative (-) battery terminal to disable the SRS system.

  1. Disconnect the floor wire from the front seat inner belt assembly LH.

  1. Connect the cable to the negative (-) battery terminal.

  1. Turn the ignition switch to ON.

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

    Standard Voltage:
    Tester Connection
    		Switch Condition
    		Specified Condition
    J67-4 (LSP+) - Body ground
    		Ignition switch ON
    		Below 1 V
    J67-3 (LSP-) - Body ground
    		Ignition switch ON
    		Below 1 V
    Text in Illustration
    *1
    		Seat Position Airbag Sensor
    *2
    		Airbag Sensor Assembly
    *3
    		Front Seat Inner Belt Assembly LH
    *4
    		Floor Wire
    *5
    		Connector C
    *a
    		Front view of wire harness connector
    (to Front Seat Inner Belt Assembly LH)


NG
REPLACE FLOOR WIRE
OK

REPLACE FRONT SEAT INNER BELT ASSEMBLY LH (YARIS_NCP93 RM000000SY000SX.html)

12.CHECK FLOOR WIRE (SHORT TO GROUND)


    Yaris. Ncp93, 131.Supplemental Restraint Systems.Airbag System (For Sedan). Dtc B1653/35 Seat Position Airbag Sensor Circuit Malfunction

  1. Disconnect the floor wire from the front seat inner belt assembly LH.

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

    Standard Resistance:
    Tester Connection
    		Condition
    		Specified Condition
    J67-4 (LSP+) - Body ground
    		Always
    		1 MΩ or higher
    J67-3 (LSP-) - Body ground
    		Always
    		1 MΩ or higher
    Text in Illustration
    *1
    		Seat Position Airbag Sensor
    *2
    		Airbag Sensor Assembly
    *3
    		Front Seat Inner Belt Assembly LH
    *4
    		Floor Wire
    *5
    		Connector C
    *a
    		Front view of wire harness connector
    (to Front Seat Inner Belt Assembly LH)


NG
REPLACE FLOOR WIRE
OK

REPLACE FRONT SEAT INNER BELT ASSEMBLY LH (YARIS_NCP93 RM000000SY000SX.html)