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:
* w/ Navigation System (for HDD):
After the power switch is turned OFF, the display and navigation module display (HDD navigation system) records various types of memory and settings. As a result, after turning the power switch OFF, be sure to wait for the time specified in the following table before disconnecting the cable from the negative (-) battery terminal.

Waiting Time before Disconnecting Cable from Negative (-) Battery Terminal:





* When disconnecting the cable, some systems need to be initialized after the cable is reconnected Repair Instruction - Initialization.

PROCEDURE

1. CHECK FOR DTC





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

(b) Clear the DTCs DTC Check / Clear.

(c) Turn the power switch OFF.

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

(e) Check for DTCs DTC Check / Clear.

OK:

DTC B1656 is not output.

HINT
Codes other than DTC B1656 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 power 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 power switch ON (IG).

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

Standard voltage:





(d) Turn the power 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 (SEAT BELT BUCKLE SWITCH)





(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 power switch ON (IG), and wait for at least 60 seconds.

(d) Clear the DTCs DTC Check / Clear.

(e) Turn the power switch OFF.

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

(g) Check for DTCs DTC Check / Clear.

OK:

DTC B1656 is not output.

HINT
Codes other than DTC B1656 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 power 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 Removal.

HINT
Perform the inspection using parts from a normally functioning 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 power switch ON (IG), and wait for at least 60 seconds.

(c) Clear the DTCs DTC Check / Clear.

(d) Turn the power switch OFF.

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

(f) Check for DTCs DTC Check / Clear.

OK:

DTC B1656 is not output.

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

NG -- REPLACE CENTER AIRBAG SENSOR ASSEMBLY Removal

OK -- REPLACE FRONT SEAT INNER BELT ASSEMBLY LH Removal