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DTC    B1651/33    Manual Cut off Switch Trouble

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DESCRIPTION

The airbag cut off switch circuit consists of the center airbag sensor assembly and airbag cut off switch.
The front passenger airbag can be optionally deactivated via this circuit by turning the airbag cut off switch to the OFF position.
If the front passenger airbag is deactivated, the passenger airbag ON/OFF indicator ("OFF") comes on to inform the passengers.
DTC B1651/33 is stored when a malfunction is detected in the airbag cut off switch circuit.

DTC No.
DTC Detecting Condition
Trouble Area
B1651/33
  1. 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 airbag cut off switch circuit.
  2. Airbag cut off switch malfunction
  3. Center airbag sensor assembly malfunction
  1. Instrument panel wire
  2. Airbag cut off switch
  3. Center airbag sensor assembly

WIRING DIAGRAM


C145458E11


INSPECTION PROCEDURE

HINT:
Terminals L16-11 (MSW+) and L16-12 (MSW-) of the center airbag sensor assembly in this circuit have an activation prevention mechanism.
This mechanism can be used to check for an open circuit in the wire harness. In case of other checks (check for short, short to ground or short to B+), this mechanism should be released.

1.CHECK CONNECTORS

  1. Turn the power switch off.

  1. Disconnect the cable from the negative (-) battery terminal.

    CAUTION:
    Wait at least 90 seconds after disconnecting the cable from the negative (-) battery terminal to disable the SRS system.

  1. Check that the connectors are properly connected to the center airbag sensor assembly and airbag cut off switch.

    OK:
    The connectors are properly connected.

    HINT:
    If the connector is not connected securely, reconnect the connector and proceed to the next inspection.

  1. Disconnect the connectors from the center airbag sensor assembly and airbag cut off switch.

  1. Check that the terminals of the connectors are not damaged.

    OK:
    The terminals are not deformed or damaged.

  1. Check that the short spring for the instrument panel wire connector with the activation prevention mechanism is not deformed or damaged.

    OK:
    The short spring is not deformed or damaged.



NG
REPLACE INSTRUMENT PANEL WIRE
OK


2.CHECK INSTRUMENT PANEL WIRE (OPEN)


    C145461E07

  1. Measure the resistance according to the value(s) in the table below.

    Standard Resistance:
    Tester Connection
    		Condition
    		Specified Condition
    L117-2 (PMC+) - L117-1 (PMC-)
    		Always
    		Below 1 Ω

    Text in Illustration 
    *1
    		Airbag Cut Off Switch
    *2
    		Center Airbag Sensor Assembly
    *3
    		Instrument Panel Wire
    *4
    		Front view of wire harness connector
    (to Center Airbag Sensor Assembly)
    *5
    		Connector B
    *6
    		Front view of wire harness connector
    (to Airbag Cut Off Switch)
    *7
    		Connector C



NG
REPLACE INSTRUMENT PANEL WIRE
OK


3.CHECK INSTRUMENT PANEL WIRE (SHORT)


    C145464E06

  1. Release the activation prevention mechanism built into connector B (Click here).

  1. Measure the resistance according to the value(s) in the table below.

    Standard Resistance:
    Tester Connection
    		Condition
    		Specified Condition
    L117-2 (PMC+) - L117-1 (PMC-)
    		Always
    		1 MΩ or higher

    Text in Illustration 
    *1
    		Airbag Cut Off Switch
    *2
    		Center Airbag Sensor Assembly
    *3
    		Instrument Panel Wire
    *4
    		Front view of wire harness connector
    (to Airbag Cut Off Switch)
    *5
    		Connector C



NG
REPLACE INSTRUMENT PANEL WIRE
OK


4.CHECK INSTRUMENT PANEL WIRE (SHORT TO B+)


    C145464E06

  1. Connect the cable to the negative (-) battery terminal.

  1. Turn the power switch on (IG).

  1. Measure the voltage according to the value(s) in the table below.

    Standard Voltage:
    Tester Connection
    		Switch Condition
    		Specified Condition
    L117-2 (PMC+) - Body ground
    		Power switch on (IG)
    		Below 1 V
    L117-1 (PMC-) - Body ground
    		Power switch on (IG)
    		Below 1 V

    Text in Illustration 
    *1
    		Airbag Cut Off Switch
    *2
    		Center Airbag Sensor Assembly
    *3
    		Instrument Panel Wire
    *4
    		Front view of wire harness connector
    (to Airbag Cut Off Switch)
    *5
    		Connector C



NG
REPLACE INSTRUMENT PANEL WIRE
OK


5.CHECK INSTRUMENT PANEL WIRE (SHORT TO GROUND)


    C145464E06

  1. Turn the power switch off.

  1. Disconnect the cable from the negative (-) battery terminal.

    CAUTION:
    Wait at least 90 seconds after disconnecting the cable from the negative (-) battery terminal to disable the SRS system.

  1. Measure the resistance according to the value(s) in the table below.

    Standard Resistance:
    Tester Connection
    		Condition
    		Specified Condition
    L117-2 (PMC+) - Body ground
    		Always
    		1 MΩ or higher
    L117-1 (PMC-) - Body ground
    		Always
    		1 MΩ or higher

    Text in Illustration 
    *1
    		Airbag Cut Off Switch
    *2
    		Center Airbag Sensor Assembly
    *3
    		Instrument Panel Wire
    *4
    		Front view of wire harness connector
    (to Airbag Cut Off Switch)
    *5
    		Connector C



NG
REPLACE INSTRUMENT PANEL WIRE
OK


6.CHECK AIRBAG CUT OFF SWITCH


    C145459E08

  1. Measure the resistance according to the value(s) in the table below.

    Standard Resistance:
    Tester Connection
    		Switch Condition
    		Specified Condition
    L117-2 (PMC+) - L117-1 (PMC-)
    		Cut off switch in ON
    		360 to 440 Ω
    L117-2 (PMC+) - L117-1 (PMC-)
    		Cut off switch in OFF
    		90 to 110 Ω

    Text in Illustration 
    *1
    		Component without harness connected:
    (Airbag Cut Off Switch)



NG
REPLACE AIRBAG CUT OFF SWITCH (Click here)
OK


7.CHECK CENTER AIRBAG SENSOR ASSEMBLY


    C126705E01

  1. Restore the released activation prevention mechanism of connector B to the original condition.

  1. Connect the connectors to the center airbag sensor assembly and airbag cut off switch.

  1. Connect the cable to the negative (-) battery terminal.

  1. Turn the power switch on (IG), and wait for at least 60 seconds.

  1. Clear the DTCs stored in the memory (Click here).

  1. Turn the power switch off.

  1. Turn the power switch on (IG), and wait for at least 60 seconds.

  1. Check for DTCs (Click here).

    OK:
    DTC B1651/33 is not output.

    Text in Illustration 
    *1
    		Airbag Cut Off Switch
    *2
    		Center Airbag Sensor Assembly

    HINT:
    Codes other than DTC B1651/33 may be output at this time, but they are not related to this check.



NG
REPLACE CENTER AIRBAG SENSOR ASSEMBLY (Click here)
OK

USE SIMULATION METHOD TO CHECK (Click here)