Toyota Sienna Service Manual: Passenger Airbag ON/OFF Indicator Circuit
Malfunction
DTC B1152/28 Passenger Airbag ON/OFF Indicator Circuit
Malfunction
DESCRIPTION

The passenger airbag ON/OFF indicator circuit consists of the center airbag
sensor assembly and
passenger airbag ON/OFF indicator.
This circuit indicates the operation condition of the front passenger airbag,
the front seat side airbag RH
and front seat belt pretensioner RH.
DTC B1152/28 is recorded when a malfunction is detected in the passenger airbag
ON/OFF indicator
circuit.
WIRING DIAGRAM

INSPECTION PROCEDURE
1 CHECK PASSENGER AIRBAG ON/OFF INDICATOR OPERATION
- Turn the ignition switch to the ON position.
- Check the passenger airbag ON/OFF indicator
operation.
HINT:
Refer to the normal condition of the passenger airbag
ON/OFF indicator

Result

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 air conditioning
control assembly.
OK:
The connectors are connected.
3 CHECK CONNECTORS
- Disconnect the connectors from the center airbag sensor
assembly and the air conditioning control assembly.
- Check that the connectors (on the center airbag sensor
assembly side and the air conditioning control assembly
side) are not damaged.
OK:
The connectors are not deformed or damaged.
4 CHECK PASSENGER AIRBAG ON/OFF INDICATOR

- Connect the connector to 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.
- Check the passenger airbag ON/OFF indicator
operation.
OK:
The passenger airbag ON/OFF indicator ("ON" and
"OFF") does not come on.
5 CHECK CENTER AIRBAG SENSOR ASSEMBLY

- Turn the ignition switch to the LOCK position.
- Disconnect the negative (-) terminal cable from the
battery, and wait for at least 90 seconds.
- Connect the connector to the air conditioning control
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 B1152/28 is not output.
HINT:
Codes other than code B1152/28 may be output at this
time, but they are not related to this check.
USE SIMULATION METHOD TO CHECK
6 CHECK INSTRUMENT PANEL WIRE (OPEN)

- 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 connector from the center airbag sensor
assembly.
- Using a service wire, connect A21-1 (P-AB) and A21-25
(PAON) 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.
Automatic air conditioning:
Standard resistance

Manual air conditioning:
Standard resistance

7 CHECK INSTRUMENT PANEL WIRE (SHORT)

- Disconnect the service wire from connector "B".
- Measure the resistance according to the value(s) in the
table below.
Automatic air conditioning:
Standard resistance

Manual air conditioning:
Standard resistance

8 CHECK INSTRUMENT PANEL WIRE (SHORT TO GROUND)

- Measure the resistance according to the value(s) in the
table below.
Automatic air conditioning:
Standard resistance

Manual air conditioning:
Standard resistance

9 CHECK INSTRUMENT PANEL WIRE (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.
Automatic air conditioning:
Standard voltage

Manual air conditioning:
Standard voltage

REPLACE AIR CONDITIONING CONTROL ASSEMBLY
10 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 air conditioning
control assembly.
OK:
The connectors are connected
11 CHECK CONNECTORS
- Disconnect the connectors from the center airbag sensor
assembly and the air conditioning control assembly.
- Check that the connectors (on the center airbag sensor
assembly side and the air conditioning control assembly
side) are not damaged.
OK:
The connectors are not deformed or damaged.
12 CHECK INSTRUMENT PANEL WIRE (OPEN)

- Using a service wire, connect A21-1 (ABON) and A21-25
(ABOF) of connector "B".
- Measure the resistance according to the value(s) in the
table below.
Automatic air conditioning:
Standard resistance

Manual air conditioning:
Standard resistance

13 CHECK INSTRUMENT PANEL WIRE (SHORT)

- Disconnect the service wire from connector "B".
- Measure the resistance according to the value(s) in the
table below.
Automatic air conditioning:
Standard resistance

Manual air conditioning:
Standard resistance

14 CHECK INSTRUMENT PANEL WIRE (SHORT TO GROUND)

- Measure the resistance according to the value(s) in the
table below.
Automatic air conditioning:
Standard resistance

Manual air conditioning:
Standard resistance

15 CHECK INSTRUMENT PANEL WIRE (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.
Automatic air conditioning:
Standard voltage

Manual air conditioning:
Standard voltage

16 CHECK WIRE HARNESS (POWER SOURCE)

- Turn the ignition switch to the LOCK position.
- Disconnect the negative (-) terminal cable from the
battery, and wait for at least 90 seconds.
- Connect the connector to the center airbag sensor
assembly.
- Turn the ignition switch to the ON position.
- Measure the voltage and resistance according to the
value(s) in the table below.
Automatic air conditioning:
Standard voltage

Manual air conditioning:
Standard voltage

17 CHECK PASSENGER AIRBAG ON/OFF INDICATOR

- Turn the ignition switch to the LOCK position.
- Disconnect the negative (-) terminal cable from the
battery, and wait for at least 90 seconds.
- Connect the connector to the air conditioning control
assembly.
- Disconnect the connector from 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.
- Check the passenger airbag ON/OFF indicator condition.
Result

18 CHECK CENTER AIRBAG SENSOR ASSEMBLY

- Turn the ignition switch to the LOCK position.
- Disconnect the negative (-) terminal cable from the
battery, and wait for at least 90 seconds.
- Connect the connector to 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 B1152/28 is not output.
HINT:
Codes other than code B1152/28 may be output at this
time, but they are not related to this check.
USE SIMULATION METHOD TO CHECK
DTC B1150/23 Occupant Classification System Malfunction
DESCRIPTION
The occupant classification system circuit consists of the center airbag
sensor assembly and the occupant
classification ECU.
...
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. ...
Other materials:
ABS Warning Light does not Come ON
WIRING DIAGRAM
Refer to ABS Warning Light Remains ON (See page BC-141).
INSPECTION PROCEDURE
1 CHECK ABS WARNING LIGHT
(a) Disconnect the skid control ECU connector.
(b) Turn the ignition switch to the ON position.
(c) Check that the ABS warning light comes on.
OK:
ABS warning light come ...
Disassembly
1. REMOVE RH SEAT REAR SEAT RECLINING COVER
Remove the 2 screws.
Remove the RH seat rear seat reclining cover by
pulling it out in the arrow mark direction shown in
the illustration.
2. REMOVE LH SEAT REAR SEAT RECLINING COVER
Remove the 2 screws.
R ...
ACC Power Source Circuit
DESCRIPTION
This circuit supplies power to the A/C amplifier and the illumination for the
clock.
WIRING DIAGRAM
INSPECTION PROCEDURE
1 INSPECT FUSE (ECU ACC)
(a) Remove the ECU ACC fuse from the engine room relay
block.
(b) Measure the resistance according to the value(s) in the
tab ...