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.
...
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DESCRIPTION
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(a) Release the 2 claw fittings and remove the air filter
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