Toyota Sienna Service Manual: Center Airbag Sensor Assembly Malfunction
DTC B1100/31 Center Airbag Sensor Assembly Malfunction
DESCRIPTION
The center airbag sensor assembly consists of the center airbag sensor
assembly, safing sensor, drive
circuit, diagnosis circuit and ignition control, etc.
It receives signals from the airbag sensor, judges whether or not the SRS must
be activated, and detects
diagnosis system malfunction.
DTC B1100/31 is recorded when a malfunction is detected in the center airbag
sensor assembly circuit.

WIRING DIAGRAM

INSPECTION PROCEDURE
HINT:
When a trouble code is displayed simultaneously with B1100/31, repair the
malfunction indicated by this
code (except B1100/31) first.
1 CHECK FRONT AIRBAG SENSOR RH CIRCUIT (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.
- Disconnect the connectors from the front airbag sensor
RH and the center airbag sensor assembly.
- Measure the resistance according to the value(s) in the
table below.
Standard resistance

2 CHECK FRONT AIRBAG SENSOR RH CIRCUIT (SHORT TO 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

3 CHECK FRONT AIRBAG SENSOR RH CIRCUIT (SHORT)

- 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

4 CHECK FRONT AIRBAG SENSOR LH CIRCUIT (SHORT TO GROUND)

- Disconnect the connector from the front airbag sensor
LH.
- Measure the resistance according to the value(s) in the
table below.
Standard resistance

5 CHECK FRONT AIRBAG SENSOR LH CIRCUIT (SHORT TO 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 FRONT AIRBAG SENSOR LH CIRCUIT (SHORT)

- 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 CENTER AIRBAG SENSOR ASSEMBLY

- Connect the connectors to the center airbag sensor
assembly, front airbag sensors RH and LH.
- 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 B1100/31 is not output.
USE SIMULATION METHOD TO CHECK
8 CHECK ENGINE ROOM MAIN WIRE (SHORT TO GROUND)

- Disconnect the engine room main wire connector from
the instrument panel wire.
- Measure the resistance according to the value(s) in the
table below.
Standard resistance

REPAIR OR REPLACE INSTRUMENT PANEL WIRE
9 CHECK ENGINE ROOM MAIN WIRE (SHORT TO B+)

- Turn the ignition switch to the LOCK position.
- Disconnect the negative (-) terminal cable from the
battery, and wait for at least 90 seconds.
- Disconnect the engine room main wire connector from
the instrument panel wire.
- 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

REPAIR OR REPLACE INSTRUMENT PANEL WIRE
10 CHECK ENGINE ROOM MAIN WIRE (SHORT)

- Disconnect the engine room main wire connector from
the instrument panel wire.
- Measure the resistance according to the value(s) in the
table below.
Standard resistance

REPAIR OR REPLACE INSTRUMENT PANEL WIRE
11 CHECK ENGINE ROOM MAIN WIRE (SHORT TO GROUND)

- Disconnect the engine room main wire connector from
the instrument panel wire.
- Measure the resistance according to the value(s) in the
table below.
Standard resistance

REPAIR OR REPLACE INSTRUMENT PANEL WIRE
12 CHECK ENGINE ROOM MAIN WIRE (SHORT TO B+)

- Turn the ignition switch to the LOCK position.
- Disconnect the negative (-) terminal cable from the
battery, and wait for at least 90 seconds.
- Disconnect the engine room main wire connector from
the instrument panel wire.
- 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

REPAIR OR REPLACE INSTRUMENT PANEL WIRE
13 CHECK ENGINE ROOM MAIN WIRE (SHORT)

- Disconnect the engine room main wire connector from
the instrument panel wire.
- Measure the resistance according to the value(s) in the
table below.
Standard resistance

REPAIR OR REPLACE INSTRUMENT PANEL WIRE
DTC B0138/72 Short to B+ in Front Pretensioner Squib LH Circuit
DESCRIPTION
The front pretensioner squib LH circuit consists of the center airbag sensor
assembly and the front seat
outer belt ass ...
DTC B1135/24 Half Connection in Center Airbag Sensor
Assembly Connectors
DESCRIPTION
The center airbag sensor assembly connector has a mechanism that electrically
detects half connection.
The ...
Other materials:
Diagnostic trouble code chart
HINT:
If a trouble code is displayed during the DTC check,
inspect the circuit listed for that code. For details of the
code, refer to the "See page" in the DTC chart.
Inspect the fuse and relay before investigating the
suspected areas shown in the table below.
W ...
Seat Position Airbag Sensor Circuit Malfunction
DTC B1153/25 Seat Position Airbag Sensor Circuit Malfunction
DESCRIPTION
The seat position airbag sensor circuit consists of the center airbag sensor
assembly and the seat
position airbag sensor.
DTC B1153/25 is recorded when a malfunction is detected in the seat position
airbag sensor cir ...
Road test
1. PROBLEM SYMPTOM CONFIRMATION
(a) Based on the result of the customer problem
analysis, try to reproduce the symptoms. If the
problem is that the transaxle does not shift up, shift
down, or the shift point is too high or too low,
conduct the following road test referring to the
automatic shi ...