Toyota Tundra Service Manual: Seat Belt Buckle Switch (LH) (B1656)

DESCRIPTION

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

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

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

Warning Indicate

Test Mode / Check Mode

B1656

Seat Belt Buckle Switch (LH)

  • The airbag sensor assembly detects a line short, short to ground or B+, or an open in the seat belt buckle switch LH circuit.
  • Front seat inner belt assembly LH (seat belt buckle switch LH) malfunction
  • Airbag sensor assembly malfunction
  • Floor wire
  • Front seat inner belt assembly LH (seat belt buckle switch LH)
  • Airbag sensor assembly

Comes on

Not applicable

WIRING DIAGRAM

CAUTION / NOTICE / HINT

NOTICE:

  • After turning the ignition switch off, waiting time may be required before disconnecting the cable from the negative (-) battery terminal. Therefore, make sure to read the disconnecting the cable from the negative (-) battery terminal notices before proceeding with work.

    Click here

  • When disconnecting the cable from the negative (-) battery terminal while performing repairs, some systems need to be initialized after the cable is reconnected.

    Click here

PROCEDURE

1.

CHECK CONNECTION OF CONNECTORS

(a) Turn the ignition switch off.

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

(c) Check that the connectors are properly connected to the airbag sensor assembly and front seat inner belt assembly LH.

OK:

Connectors are properly connected.

NG

CONNECT CONNECTORS PROPERLY

OK

2.

CHECK CONNECTORS

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

*1

Front Seat Inner Belt Assembly LH

*2

Airbag Sensor Assembly

*3

Floor Wire

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

OK:

Connectors are not deformed or damaged.

NG

REPLACE FLOOR WIRE

OK

3.

CHECK FLOOR WIRE

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

*1

Front Seat Inner Belt Assembly LH

*2

Airbag Sensor Assembly

*3

Floor Wire

*4

Service Wire

*a

Front view of wire harness connector

(to Front Seat Inner Belt Assembly LH)

*b

Front view of wire harness connector

(to Airbag Sensor Assembly)

(b) Turn the ignition switch to ON.

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

Standard Voltage:

Tester Connection

Switch Condition

Specified Condition

P7-1 (LBE+) - Body ground

Ignition switch ON

Below 1 V

P7-2 (LBE-) - Body ground

Ignition switch ON

Below 1 V

(d) Turn the ignition switch off.

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

(f) Using a service wire, connect terminals 28 (LBE+) and 27 (LBE-) of connector B.

NOTICE:

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

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

P7-1 (LBE+) - P7-2 (LBE-)

Always

Below 1 Ω

(h) Disconnect the service wire from connector B.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

P7-1 (LBE+) - P7-2 (LBE-)

Always

1 MΩ or higher

P7-1 (LBE+) - Body ground

Always

1 MΩ or higher

P7-2 (LBE-) - Body ground

Always

1 MΩ or higher

NG

REPLACE FLOOR WIRE

OK

4.

CHECK DTC

(a) Connect the connectors to the airbag sensor assembly and front seat inner belt assembly LH.

*1

Front Seat Inner Belt Assembly LH

*2

Airbag Sensor Assembly

(b) Connect the cable to the negative (-) battery terminal, 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.

Click here

(e) Turn the ignition switch off.

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

(g) Check for DTCs.

Click here

Result

Proceed to

DTC B1656 is not output

A

DTC B1656 is output

B

HINT:

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

B

USE SIMULATION METHOD TO CHECK

A

5.

REPLACE FRONT SEAT INNER BELT ASSEMBLY LH

(a) Turn the ignition switch off.

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

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

for Center Seat Type:

Click here

except Center Seat:

Click here

HINT:

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

NEXT

6.

CHECK DTC

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

*1

Front Seat Inner Belt Assembly LH

*2

Airbag Sensor Assembly

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

(c) Clear the DTCs.

Click here

(d) Turn the ignition switch off.

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

(f) Check for DTCs.

Click here

Result

Proceed to

DTC B1656 is not output

A

DTC B1656 is output

B

HINT:

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

A

END (FRONT SEAT INNER BELT ASSEMBLY LH WAS DEFECTIVE)

B

REPLACE AIRBAG SENSOR ASSEMBLY

    Seat Position Airbag Sensor Circuit Malfunction (B1653)

    P Seat Airbag Active Mode Indicator (B1660)

    See More:

    Toyota Tundra Service Manual > Dynamic Radar Cruise Control System: Skid Control Buzzer Circuit (C1A4A)
    DESCRIPTION Based on dynamic radar cruise control system operation, the forward recognition camera provides warnings to the driver by sounding the skid control buzzer assembly. DTC C1A4A is stored when a malfunction is detected in the skid control buzzer assembly circuit. DTC No. Detection Item DTC ...

    Toyota Tundra Owners Manual

    Toyota Tundra Service Manual

    © 2024 Copyright www.ttundra.com
    0.0205