B1656

SUPPLEMENTAL RESTRAINT SYSTEM: AIRBAG SYSTEM: B1656/38: Seat Belt Buckle Switch LH Circuit Malfunction
B1656/38 - Seat Belt Buckle Switch LH Circuit Malfunction

DESCRIPTION

The seat belt buckle switch LH circuit consists of the center airbag sensor and the front seat inner belt LH.

DTC B1656/38 is recorded when a malfunction is detected in the seat belt buckle switch LH circuit.





WIRING DIAGRAM





INSPECTION PROCEDURE

NOTICE:
After the engine switch is turned off, the HDD navigation system requires approximately 6 minutes to record various types of memory and settings. As a result, after turning the engine switch off, wait 6 minutes or more before disconnecting the cable from the negative (-) battery terminal.

PROCEDURE

1. CHECK FOR DTC





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

(b) Clear the DTCs Reading and Clearing Diagnostic Trouble Codes.

(c) Turn the engine switch off.

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

(e) Check for DTCs Reading and Clearing Diagnostic Trouble Codes.

OK:

DTC B1656/38 is not output.

HINT
Codes other than DTC B1656/38 may be output at this time, but they are not related to this check.

NG -- CHECK CONNECTION OF CONNECTORS

OK -- USE SIMULATION METHOD TO CHECK Diagnosis System

2. CHECK CONNECTION OF CONNECTORS

(a) Turn the engine 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 and front seat inner belt LH.

OK:

The connectors are properly connected.

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

3. CHECK CONNECTORS

(a) Disconnect the connectors from the center airbag sensor and the front seat inner belt LH.

(b) Check that the connectors (on the center airbag sensor side and front seat inner belt LH side) are not damaged.

OK:

The connectors are not deformed or damaged.

NG -- REPLACE NO. 2 FLOOR WIRE
OK -- Continue to next step.

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





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

(b) Turn the engine switch on (IG).

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

Standard voltage:





(d) Turn the engine switch off.

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

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

Standard resistance:





NG -- REPLACE NO. 2 FLOOR WIRE
OK -- Continue to next step.

5. CHECK FRONT SEAT INNER BELT LH





(a) Connect the connector to the center airbag sensor and the front seat inner belt LH.

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

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

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

(e) Turn the engine switch off.

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

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

OK:

DTC B1656/38 is not output.

HINT
Codes other than DTC B1656/38 may be output at this time, but they are not related to this check.

NG -- REPLACE FRONT SEAT INNER BELT LH

OK -- USE SIMULATION METHOD TO CHECK Diagnosis System

6. REPLACE FRONT SEAT INNER BELT LH

(a) Turn the engine switch off.

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

(c) Replace the front seat inner belt LH Components.

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

NEXT -- Continue to next step.

7. CHECK CENTER AIRBAG SENSOR





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

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

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

(d) Turn the engine switch off.

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

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

OK:

DTC B1656/38 is not output.

HINT
Codes other than DTC B1656/38 may be output at this time, but they are not related to this check.

NG -- REPLACE CENTER AIRBAG SENSOR ASSEMBLY Components

OK -- REPLACE SEAT INNER BELT ASSEMBLY LH Components