Toyota Sienna Service Manual: Seat Belt Buckle Switch LH Circuit Malfunction
DTC B0126/27 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 B0126/27 is recorded when a malfunction is detected in the seat belt buckle
switch LH circuit
WIRING DIAGRAM
INSPECTION PROCEDURE
1 CHECK DTC
- Turn the ignition switch to the ON position, and wait for at
least 60 seconds.
- Clear the DTCs stored in memory.
- Turn the ignition switch to the LOCK position.
- Turn the ignition switch to the ON position, and wait for at
least 60 seconds.
- Check the DTCs.
OK:
DTC B0126/27 is not output.
HINT:
Codes other than code B0126/27 may be output at this
time, but they are not related to this check.
USE SIMULATION METHOD TO CHECK
2 CHECK CONNECTION OF CONNECTORS
- Turn the ignition switch to the LOCK position.
- Disconnect the negative (-) terminal cable from the
battery, and wait for at least 90 seconds.
- Check that the connectors are properly connected to the
center airbag sensor assembly and the front seat inner
belt assembly LH.
OK:
The connectors are connected.
3 CHECK VEHICLE
- Check the front driver seat type.
Result
4 CHECK FLOOR WIRE (OPEN)
- Disconnect the connectors from the center airbag sensor
assembly and the front seat inner belt assembly LH.
- w/ Side airbag:
Using a service wire, connect A20-19 (LBE+) and A20-2
(LBE-) of connector "B".
NOTICE:
Do not forcibly insert a service wire into the
terminals of the connector when connecting.
- w/o Side airbag:
Using a service wire, connect A20-11 (LBE+) and A20-6
(LBE-) of connector "B".
NOTICE:
Do not forcibly insert a service wire into the
terminals of the connector when connecting.
- Measure the resistance according to the value(s) in the
table below.
Standard resistance
5 CHECK FLOOR WIRE (SHORT TO B+)
- Disconnect the service wire from connector "B".
- Connect the negative (-) terminal cable to the battery,
and wait for at least 2 seconds.
- Turn the ignition switch to the ON position.
- Measure the voltage according to the value(s) in the
table below.
Standard voltage
6 CHECK FLOOR WIRE (SHORT TO GROUND)
- Turn the ignition switch to the LOCK position.
- Disconnect the negative (-) terminal cable from the
battery, and wait for at least 90 seconds.
- Measure the resistance according to the value(s) in the
table below.
Standard resistance
7 CHECK FLOOR WIRE (SHORT)
- Measure the voltage according to the value(s) in the
table below.
Standard resistance
8 CHECK FRONT SEAT INNER BELT ASSEMBLY LH
- Connect the connectors to the front seat inner belt
assembly LH and the center airbag sensor assembly.
- Connect the negative (-) terminal cable to the battery,
and wait for at least 2 seconds.
- Turn the ignition switch to the ON position, and wait for at
least 60 seconds.
- Clear the DTCs stored in memory.
- Turn the ignition switch to the LOCK position.
- Turn the ignition switch to the ON position, and wait for at
least 60 seconds.
- Check the DTCs.
OK:
DTC B0126/27 is not output.
HINT:
Codes other than code B0126/27 may be output at this
time, but they are not related to this check.
USE SIMULATION METHOD TO CHECK
9 REPLACE FRONT SEAT INNER BELT ASSEMBLY LH
- Turn the ignition switch to the LOCK position.
- Disconnect the negative (-) terminal cable from the
battery, and wait for at least 90 seconds.
- Replace the front seat inner belt assembly LH.
HINT:
Perform the inspection using parts from a normal vehicle
if possible.
10 CHECK CENTER AIRBAG SENSOR ASSEMBLY
- Connect the negative (-) terminal cable to the battery,
and wait for at least 2 seconds.
- Turn the ignition switch to the ON position, and wait for at
least 60 seconds.
- Clear the DTCs stored in memory.
- Turn the ignition switch to the LOCK position.
- Turn the ignition switch to the ON position, and wait for at
least 60 seconds.
- Check the DTCs.
OK:
DTC B0126/27 is output.
HINT:
Codes other than code B0126/27 may be output at this
time, but they are not related to this check.
END
11 CHECK FLOOR WIRE (OPEN)
- Disconnect the connectors from the center airbag sensor
assembly and the front seat inner belt assembly LH.
- w/ Side airbag:
Using a service wire, connect A20-19 (LBE+) and A20-2
(LBE-) of connector "B".
NOTICE:
Do not forcibly insert a service wire into the
terminals of the connector when connecting.
- w/o Side airbag:
Using a service wire, connect A20-11 (LBE+) and A20-6
(LBE-) of connector "B".
NOTICE:
Do not forcibly insert a service wire into the
terminals of the connector when connecting.
- Measure the resistance according to the value(s) in the
table below.
Standard resistance
12 CHECK FLOOR WIRE (SHORT TO B+)
- Disconnect the service wire from connector "B".
- Connect the negative (-) terminal cable to the battery,
and wait for at least 2 seconds.
- Turn the ignition switch to the ON position.
- Measure the voltage according to the value(s) in the
table below.
Standard voltage
13 CHECK FLOOR WIRE (SHORT TO GROUND)
- Turn the ignition switch to the LOCK position.
- Disconnect the negative (-) terminal cable from the
battery, and wait for at least 90 seconds.
- Measure the resistance according to the value(s) in the
table below.
Standard resistance
14 CHECK FLOOR WIRE (SHORT)
- Measure the resistance according to the value(s) in the
table below.
Standard resistance
15 CHECK FRONT SEAT INNER BELT ASSEMBLY LH
- Connect the connectors to the front seat inner belt
assembly LH and the center airbag sensor assembly.
- Connect the negative (-) terminal cable to the battery,
and wait for at least 2 seconds.
- Turn the ignition switch to the ON position, and wait for at
least 60 seconds.
- Clear the DTCs stored in memory.
- Turn the ignition switch to the LOCK position.
- Turn the ignition switch to the ON position, and wait for at
least 60 seconds.
- Check the DTCs.
OK:
DTC B0126/27 is not output.
HINT:
Codes other than code B0126/27 may be output at this
time, but they are not related to this check.
USE SIMULATION METHOD TO CHECK
16 REPLACE FRONT SEAT INNER BELT ASSEMBLY LH
- Turn the ignition switch to the LOCK position.
- Disconnect the negative (-) terminal cable from the
battery, and wait for at least 90 seconds.
- Replace the front seat inner belt assembly LH.
HINT:
Perform the inspection using parts from a normal vehicle
if possible.
17 CHECK CENTER AIRBAG SENSOR ASSEMBLY
- Connect the negative (-) terminal cable to the battery,
and wait for at least 2 seconds.
- Turn the ignition switch to the ON position, and wait for at
least 60 seconds.
- Clear the DTCs stored in memory.
- Turn the ignition switch to the LOCK position.
- Turn the ignition switch to the ON position, and wait for at
least 60 seconds.
- Check the DTCs.
OK:
DTC B0126/27 is not output.
HINT:
Codes other than code B0126/27 may be output at this
time, but they are not related to this check.
END
DTC B0118/46 Short to B+ in Side Squib LH Circuit
DESCRIPTION
The side squib LH circuit consists of the center airbag sensor assembly and
the front seat side airbag
assembly LH (side squib LH).
...
DTC B0130/63 Short in Front Pretensioner Squib RH Circuit
DESCRIPTION
The front pretensioner squib RH circuit consists of the center airbag sensor
assembly and the front seat
outer belt assembly ...
Other materials:
Front Occupant Classification Sensor LH Collision
Detection
DTC B1785 Front Occupant Classification Sensor LH Collision
Detection
DESCRIPTION
DTC B1785 is output when the occupant classification ECU receives a collision
detection signal sent by
the front occupant classification sensor LH if an accident occurs.
DTC B1785 is also output when the front ...
Problem symptoms table
HINT:
Inspect the fuse and relay before confirming the suspected
areas in the table below.
Inspect each suspected area in numerical order for the
corresponding symptom.
If the malfunction still exists after checking and confirming
that all circuits and components are normal ...
SRS Warning Light Remains ON
DESCRIPTION
The SRS warning light is located on the combination meter assembly.
When the SRS is normal, the SRS warning light comes on for approximately 6
seconds after the ignition
switch is turned from the LOCK position to ON position, and then goes off
automatically.
If there is a mal ...