- The center 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 belt buckle switch LH circuit for 2 seconds.
- Front seat inner belt assembly LH malfunction
- Center airbag sensor assembly malfunction
| Last Modified: 04-05-2023 | 6.11:8.1.0 | Doc ID: RM100000000VJRB |
| Model Year Start: 2016 | Model: Sienna | Prod Date Range: [12/2015 - ] |
| Title: SUPPLEMENTAL RESTRAINT SYSTEMS: AIRBAG SYSTEM: B1656/38; Seat Belt Buckle Switch LH Circuit Malfunction; 2016 - 2020 MY Sienna [12/2015 - ] | ||
|
DTC |
B1656/38 |
Seat Belt Buckle Switch LH Circuit Malfunction |
DESCRIPTION
The seat belt buckle switch LH circuit consists of the center airbag sensor assembly and the front seat inner belt assembly LH.
DTC B1656/38 is recorded when a malfunction is detected in the seat belt buckle switch LH circuit.
|
DTC No. |
DTC Detection Condition |
Trouble Area |
|---|---|---|
|
B1656/38 |
When one of following conditions is met: |
|
WIRING DIAGRAM
PROCEDURE
|
1. |
CHECK CONNECTION OF CONNECTORS |
(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 front seat inner belt assembly LH.
OK:
The connectors are properly connected.
| NG |
|
CONNECT CONNECTORS PROPERLY |
|
|
2. |
CHECK CONNECTORS |
(a) Disconnect the connectors from the center airbag sensor assembly and the front seat inner belt assembly LH.
(b) Check that the connectors (on the center airbag sensor assembly side and front seat inner belt assembly LH side) are not damaged.
OK:
The connectors are not deformed or damaged.
| NG |
|
REPLACE FLOOR WIRE |
|
|
3. |
CHECK FLOOR WIRE (CENTER AIRBAG SENSOR ASSEMBLY - FRONT SEAT INNER BELT ASSEMBLY LH) |
Text in Illustration
|
*1 |
Front Seat Inner Belt Assembly LH |
*2 |
Center Airbag Sensor Assembly |
|
*3 |
Floor Wire |
*4 |
Connector C |
|
*5 |
Connector B |
*6 |
Service Wire |
|
*a |
Front view of wire harness connector (to Front Seat Inner Belt Assembly LH) |
*b |
Rear view of wire harness connector (to 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.
(c) Measure the voltage according to the value(s) in the table below.
Standard Voltage:
|
Tester Connection |
Switch Condition |
Specified Condition |
|---|---|---|
|
K24-2 (LBE+) - Body ground |
Ignition switch ON |
Below 1 V |
|
K24-1 (LBE-) - Body ground |
Ignition switch ON |
Below 1 V |
(d) Turn the ignition switch off.
(e) Disconnect the negative (-) terminal cable from the battery, and wait for at least 90 seconds.
(f) Using a service wire, connect terminals 10 (LBE+) and 18 (LBE-) of connector B.
NOTICE:
Do not forcibly insert a service wire into the terminals of the connector when connecting the wire.
(g) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
|
Tester Connection |
Condition |
Specified Condition |
|---|---|---|
|
K24-2 (LBE+) - K24-1 (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 |
|---|---|---|
|
K24-2 (LBE+) - K24-1 (LBE-) |
Always |
1 MΩ or higher |
|
K24-2 (LBE+) - Body ground |
Always |
1 MΩ or higher |
|
K24-1 (LBE-) - Body ground |
Always |
1 MΩ or higher |
| NG |
|
REPLACE FLOOR WIRE |
|
|
4. |
CHECK FRONT SEAT INNER BELT ASSEMBLY LH (DRIVER SIDE) |
(a) Connect the connector to the center airbag sensor assembly and the front seat inner belt assembly LH.
(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 (See page
![2016 - 2020 MY Sienna [12/2015 - ]; SUPPLEMENTAL RESTRAINT SYSTEMS: AIRBAG SYSTEM: DTC CHECK / CLEAR](/t3Portal/stylegraphics/info.gif)
).
(e) Turn the ignition switch off.
(f) Turn the ignition switch to ON, and wait for at least 60 seconds.
(g) Check for DTCs (See page
).
OK:
DTC B1656/38 is not output.
Text in Illustration
|
*1 |
Front Seat Inner Belt Assembly LH |
|
*2 |
Center Airbag Sensor Assembly |
HINT:
DTCs other than B1656/38 may be output at this time, but they are not related to this check.
| OK |
|
|
|
5. |
REPLACE FRONT SEAT INNER BELT ASSEMBLY LH |
(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 front seat inner belt assembly LH (See page
).
HINT:
Perform inspection using parts from a normal vehicle if possible.
|
|
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 (See page
).
(d) Turn the ignition switch off.
(e) Turn the ignition switch to ON, and wait for at least 60 seconds.
(f) Check for DTCs (See page
).
OK:
DTC B1656/38 is not output.
Text in Illustration
|
*1 |
Front Seat Inner Belt Assembly LH |
|
*2 |
Center Airbag Sensor Assembly |
HINT:
DTCs other than B1656/38 may be output at this time, but they are not related to this check.
| OK |
|
END |
| NG |
|
|
|