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DTC    B1800/51    Short in Driver Side Squib Circuit

DTC    B1801/51    Open in Driver Side Squib Circuit

DTC    B1802/51    Short to GND in Driver Side Squib Circuit

DTC    B1803/51    Short to B+ in Driver Side Squib Circuit

for Preparation Click here


DESCRIPTION

  1. The driver side squib circuit consists of the center airbag sensor assembly, spiral cable and steering pad.
  2. The circuit instructs SRS to deploy when deployment conditions are met.
  3. These DTCs are stored when a malfunction is detected in the driver side squib circuit.

DTC No.
DTC Detection Condition
Trouble Area
B1800/51
  1. The center airbag sensor assembly receives a line short circuit signal in the driver side squib circuit during primary check.
  2. Driver side squib malfunction
  3. Spiral cable malfunction
  4. Center airbag sensor assembly malfunction
  1. Instrument panel wire
  2. Spiral cable
  3. Steering pad (Driver side squib)
  4. Center airbag sensor assembly
B1801/51
  1. The center airbag sensor assembly receives an open circuit signal in the driver side squib circuit.
  2. Driver side squib malfunction
  3. Spiral cable malfunction
  4. Center airbag sensor assembly malfunction
  1. Instrument panel wire
  2. Spiral cable
  3. Steering pad (Driver side squib)
  4. Center airbag sensor assembly
B1802/51
  1. The center airbag sensor assembly receives a short circuit to ground signal in the driver side squib circuit.
  2. Driver side squib malfunction
  3. Spiral cable malfunction
  4. Center airbag sensor assembly malfunction
  1. Instrument panel wire
  2. Spiral cable
  3. Steering pad (Driver side squib)
  4. Center airbag sensor assembly
B1803/51
  1. The center airbag sensor assembly receives a short circuit to B+ signal in the driver side squib circuit.
  2. Driver side squib malfunction
  3. Spiral cable malfunction
  4. Center airbag sensor assembly malfunction
  1. Instrument panel wire
  2. Spiral cable
  3. Steering pad (Driver side squib)
  4. Center airbag sensor assembly

WIRING DIAGRAM


C145466E34


INSPECTION PROCEDURE

HINT:
  1. Perform the simulation method by selecting check mode (Signal Check) using the intelligent tester (Click here).
  2. After selecting check mode (Signal Check), perform the simulation method by wiggling each connector of the airbag system or driving the vehicle on a city or rough road (Click here).

1.CHECK CONNECTORS


    C165138E03

  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 steering pad, spiral cable and center airbag sensor assembly.

    OK:
    The connectors are properly connected.

    HINT:
    If the connectors are not connected securely, reconnect the connectors and proceed to the next inspection.

  1. Disconnect the connectors from the steering pad, spiral cable and center airbag sensor assembly.

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

    OK:
    The terminals are not deformed or damaged.

  1. Check that the spiral cable connector (on the steering pad side) is not damaged.

    OK:
    The lock button is not disengaged, or the claw of the lock is not deformed or damaged.

  1. Check that the short springs for the instrument panel wire and spiral cable with the activation prevention mechanism are not deformed or damaged.

    OK:
    The short springs are not deformed or damaged.

    Text in Illustration 
    *1
    		Driver Side Squib
    *2
    		Spiral Cable
    *3
    		Center Airbag Sensor Assembly
    *4
    		Instrument Panel Wire



NG
REPLACE WIRE HARNESS
OK


2.CHECK STEERING PAD (DRIVER SIDE SQUIB)
C190149E10

  1. Connect the instrument panel wire to the center airbag sensor assembly and spiral cable.

  1. Connect SST (resistance 2.1 Ω) to connector E.

    CAUTION:
    Never connect the tester to the steering pad (driver side squib) for measurement, as this may lead to a serious injury due to airbag deployment.

    NOTICE:
    1. Do not forcibly insert SST into the terminals of the connector when connecting.
    2. Insert SST straight into the terminals of the connector.

SST
09843-18061  

  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 B1800, B1801, B1802, B1803 or 51 is not output.

    Text in Illustration 
    *1
    		Driver Side Squib
    *2
    		Spiral Cable
    *3
    		Center Airbag Sensor Assembly
    *4
    		Front view of wire harness connector
    (to Steering Pad)
    *5
    		Connector E

    HINT:
    Codes other than DTCs B1800, B1801, B1802, B1803 and 51 may be output at this time, but they are not related to this check.



NG
Go to step 3
OK

REPLACE STEERING PAD (Click here)  

3.CHECK DRIVER SIDE SQUIB CIRCUIT


    C157576E23

  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. Disconnect SST from connector E.

  1. Disconnect the instrument panel wire from the center airbag sensor assembly.

  1. Check for a short to B+ in the circuit.

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

    2. Turn the power switch on (IG).

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

      Standard Voltage:
      Tester Connection
      		Switch Condition
      		Specified Condition
      z8-2 (D+) - Body ground
      		Power switch on (IG)
      		Below 1 V
      z8-1 (D-) - Body ground
      		Power switch on (IG)
      		Below 1 V

  1. Check for an open in the circuit.

    1. Turn the power switch off.

    2. 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.

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

      Standard Resistance:
      Tester Connection
      		Condition
      		Specified Condition
      z8-2 (D+) - z8-1 (D-)
      		Always
      		Below 1 Ω

  1. Check for a short to ground in the circuit.

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

      Standard Resistance:
      Tester Connection
      		Condition
      		Specified Condition
      z8-2 (D+) - Body ground
      		Always
      		1 MΩ or higher
      z8-1 (D-) - Body ground
      		Always
      		1 MΩ or higher

  1. Check for a short in the circuit.

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

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

      Standard Resistance:
      Tester Connection
      		Condition
      		Specified Condition
      z8-2 (D+) - z8-1 (D-)
      		Always
      		1 MΩ or higher

      Text in Illustration 
      *1
      		Driver Side Squib
      *2
      		Spiral Cable
      *3
      		Center Airbag Sensor Assembly
      *4
      		Front view of wire harness connector
      (to Steering Pad)
      *5
      		Connector E



NG
Go to step 5
OK


4.CHECK CENTER AIRBAG SENSOR ASSEMBLY


    C170962E03

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

  1. Connect the connectors to the steering pad and center airbag sensor assembly.

  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 B1800, B1801, B1802, B1803 or 51 is not output.

    Text in Illustration 
    *1
    		Driver Side Squib
    *2
    		Spiral Cable
    *3
    		Center Airbag Sensor Assembly

    HINT:
    Codes other than DTCs B1800, B1801, B1802, B1803 and 51 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)  

5.CHECK INSTRUMENT PANEL WIRE


    C167900E22

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

  1. Disconnect the instrument panel wire from the spiral cable.

  1. Check for a short to B+ in the circuit.

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

    2. Turn the power switch on (IG).

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

      Standard Voltage:
      Tester Connection
      		Switch Condition
      		Specified Condition
      L53-1 (D+) - Body ground
      		Power switch on (IG)
      		Below 1 V
      L53-2 (D-) - Body ground
      		Power switch on (IG)
      		Below 1 V

  1. Check for an open in the circuit.

    1. Turn the power switch off.

    2. 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.

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

      Standard Resistance:
      Tester Connection
      		Condition
      		Specified Condition
      L53-1 (D+) - L53-2 (D-)
      		Always
      		Below 1 Ω

  1. Check for a short to ground in the circuit.

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

      Standard Resistance:
      Tester Connection
      		Condition
      		Specified Condition
      L53-1 (D+) - Body ground
      		Always
      		1 MΩ or higher
      L53-2 (D-) - Body ground
      		Always
      		1 MΩ or higher

  1. Check for a short in the circuit.

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

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

      Standard Resistance:
      Tester Connection
      		Condition
      		Specified Condition
      L53-1 (D+) - L53-2 (D-)
      		Always
      		1 MΩ or higher

      Text in Illustration 
      *1
      		Driver Side Squib
      *2
      		Spiral Cable
      *3
      		Center Airbag Sensor Assembly
      *4
      		Instrument Panel Wire
      *5
      		Front view of wire harness connector
      (to Spiral Cable)
      *6
      		Connector C



NG
REPLACE INSTRUMENT PANEL WIRE
OK


6.CHECK SPIRAL CABLE


    C157585E21

  1. Check for a short to B+ in the circuit.

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

    2. Turn the power switch on (IG).

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

      Standard Voltage:
      Tester Connection
      		Switch Condition
      		Specified Condition
      z8-2 (D+) - Body ground
      		Power switch on (IG)
      		Below 1 V
      z8-1 (D-) - Body ground
      		Power switch on (IG)
      		Below 1 V

  1. Check for an open in the circuit.

    1. Turn the power switch off.

    2. 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.

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

      Standard Resistance:
      Tester Connection
      		Condition
      		Specified Condition
      z8-2 (D+) - z8-1 (D-)
      		Always
      		Below 1 Ω

  1. Check for a short to ground in the circuit.

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

      Standard Resistance:
      Tester Connection
      		Condition
      		Specified Condition
      z8-2 (D+) - Body ground
      		Always
      		1 MΩ or higher
      z8-1 (D-) - Body ground
      		Always
      		1 MΩ or higher

  1. Check for a short in the circuit.

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

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

      Standard Resistance:
      Tester Connection
      		Condition
      		Specified Condition
      z8-2 (D+) - z8-1 (D-)
      		Always
      		1 MΩ or higher

      Text in Illustration 
      *1
      		Driver Side Squib
      *2
      		Spiral Cable
      *3
      		Center Airbag Sensor Assembly
      *4
      		Instrument Panel Wire
      *5
      		Front view of wire harness connector
      (to Steering Pad)
      *6
      		Connector E



NG
REPLACE SPIRAL CABLE (Click here)
OK

USE SIMULATION METHOD TO CHECK (Click here)