B1653

SUPPLEMENTAL RESTRAINT SYSTEM: AIRBAG SYSTEM: B1653/35: Seat Position Airbag Sensor Circuit Malfunction
B1653/35 - Seat Position Airbag Sensor Circuit Malfunction

DESCRIPTION

The seat position sensor circuit consists of the center airbag sensor assembly and the seat position sensor.

DTC B1653/35 is recorded when a malfunction is detected in the seat position sensor circuit.





WIRING DIAGRAM





INSPECTION PROCEDURE

NOTICE:
In order to prevent unexpected airbag deployment, disconnect the following connectors before inspecting parts such as wire harnesses, if the application of tester probes to the center airbag sensor assembly connector is necessary.

1. Turn the ignition switch off.

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

3. Disconnect the connector from the center airbag sensor assembly.

4. Disconnect the connectors from the steering pad.

5. Disconnect the connectors from the front passenger airbag assembly.

6. Disconnect the connector from the front seat outer belt assembly LH

7. Disconnect the connector from the front seat outer belt assembly RH.

8. Disconnect the connector from the front seat side airbag assembly LH.

9. Disconnect the connector from the front seat side airbag assembly RH.

10. Disconnect the connector from the curtain shield airbag assembly LH.

11. Disconnect the connector from the curtain shield airbag assembly RH.

PROCEDURE

1. CHECK CONNECTOR CONNECTION CONDITION

(a) Turn the ignition switch off.

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

(c) Check that the connectors are properly connected to the center airbag sensor assembly and the seat position airbag sensor.

OK:

The connectors are properly connected.

NG -- CONNECT CONNECTORS
OK -- Continue to next step.

2. CHECK CONNECTORS

(a) Disconnect the connectors from the center airbag sensor assembly and the seat position airbag sensor.

(b) Check that the connectors (on the center airbag sensor assembly side and seat position airbag sensor side) are not damaged.

OK:

The connectors are not deformed or damaged.

NG -- REPLACE HARNESS AND CONNECTOR
OK -- Continue to next step.

3. CHECK SEAT POSITION SENSOR CIRCUIT (CENTER AIRBAG SENSOR - SEAT POSITION AIRBAG SENSOR)





(a) Check for short to B+ in the circuit.

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

(2) Turn the ignition switch to ON.

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

Standard Voltage:





(4) Turn the ignition switch off.

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

(b) Check for open in the circuit.

(1) Disconnect the connectors from the center airbag sensor assembly and the seat position airbag sensor.

(2) Using a service wire, connect L1-9 (DSP+) and L1-17 (DSP-) of connector B.

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

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

Standard Resistance:





(c) Check for short in the circuit.

(1) Disconnect the service wire from connector B.

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

Standard Resistance:





(d) Check for short to ground in the circuit.

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

Standard Resistance:





NG -- CHECK NO. 2 FLOOR WIRE (CENTER AIRBAG SENSOR - FRONT SEAT INNER BELT LH)
OK -- Continue to next step.

4. CHECK SEAT POSITION AIRBAG SENSOR

(a) Connect the connectors to the center airbag sensor assembly and the seat position airbag sensor.





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

(c) Turn the ignition switch to ON, and wait for at least 60 seconds.

(d) Clear the DTCs stored in the memory Reading and Clearing Diagnostic Trouble Codes.

(e) Turn the ignition switch off.

(f) Turn the ignition switch to ON, and wait for at least 60 seconds.

(g) Check the DTCs Reading and Clearing Diagnostic Trouble Codes.

OK:

DTC B1653/35 is not output.

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

NG -- REPLACE SEAT POSITION AIRBAG SENSOR

OK -- USE SIMULATION METHOD TO CHECK Diagnosis System

5. REPLACE SEAT POSITION AIRBAG SENSOR

(a) Turn the ignition switch off.

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

(c) Replace the seat position airbag sensor Removal.

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

NEXT -- Continue to next step.

6. CHECK CENTER AIRBAG SENSOR ASSEMBLY

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





(b) Turn the ignition switch to ON, and wait for at least 60 seconds.

(c) Clear the DTCs stored in the memory Reading and Clearing Diagnostic Trouble Codes.

(d) Turn the ignition switch off.

(e) Turn the ignition switch to ON, and wait for at least 60 seconds.

(f) Check the DTCs Reading and Clearing Diagnostic Trouble Codes.

OK:

DTC B1653/35 is not output.

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

NG -- REPLACE CENTER AIRBAG SENSOR ASSEMBLY Removal

OK -- END

7. CHECK NO. 2 FLOOR WIRE (CENTER AIRBAG SENSOR - FRONT SEAT INNER BELT LH)





(a) Check for short to B+ in the circuit.

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

(2) Turn the ignition switch to ON.

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

Standard Voltage:





(4) Turn the ignition switch off.

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

(b) Check for open in the circuit.

(1) Disconnect the connectors from the front seat inner belt assembly (wire harness) and the No. 2 floor wire.

(2) Using a service wire, connect L1-9 (DSP+) and L1-17 (DSP-) of connector B.

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

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

Standard Resistance:





(c) Check for short in the circuit.

(1) Disconnect the service wire from connector B.

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

Standard Resistance:





(d) Check for short to ground in the circuit.

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

Standard Resistance:





NG -- REPLACE NO. 2 FLOOR WIRE

OK -- REPLACE FRONT SEAT INNER BELT ASSEMBLY LH Removal