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Home >> Toyota >> 2012 >> Prius Four >> Repair and Diagnosis (Single Page) >> Restraints >> Restraints Control Systems >> Supplemental Restraint System (Except Plug-In) (Diagnostic Codes & Symptom Tests) >> Airbag System >> 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 >> Procedure
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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: Procedure

  1. CHECK CONNECTORS 
    1. Turn the power switch off.
      Fig 1: Identifying Driver Side Squib 2nd Step Circuit & Spiral Cable Connectors
      GTY216069Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Disconnect the cable from the negative (-) battery terminal.
      WARNING:

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

    3. 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.

    4. Disconnect the connectors from the steering pad, spiral cable and center airbag sensor assembly.
    5. Check that the terminals of the connectors are not damaged.

      OK

      The terminals are not deformed or damaged.

    6. 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.

    7. 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: Go to next step 

  2. CHECK STEERING PAD (DRIVER SIDE SQUIB) 
    1. Connect the instrument panel wire to the center airbag sensor assembly and spiral cable.
      Fig 2: Identifying z8 Connector Terminals
      GTY226513Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Connect SST (resistance 2.1 Ω) to connector E (orange connector).
      WARNING:

      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.

      NOTE:
      • Do not forcibly insert SST into the terminals of the connector when connecting.
      • Insert SST straight into the terminals of the connector.
      • SST: 09843-18061 
    3. Connect the cable to the negative (-) battery terminal.
    4. Turn the power switch on (IG), and wait for at least 60 seconds.
    5. Clear the DTCs stored in the memory. Refer to DTC CHECK / CLEAR .
    6. Turn the power switch off.
    7. Turn the power switch on (IG), and wait for at least 60 seconds.
    8. Check for DTCs. Refer to DTC CHECK / CLEAR .

      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
      *6 Color: Orange

      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 → See step   3 

    OK → See step   8 

  3. CHECK DRIVER SIDE SQUIB CIRCUIT 
    1. Turn the power switch off.
      Fig 3: Identifying z8 Connector Terminals
      GTY215463Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Disconnect the cable from the negative (-) battery terminal.
      WARNING:

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

    3. Disconnect SST from connector E.
    4. Disconnect the instrument panel wire from the center airbag sensor assembly.
    5. 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
    6. Check for an open in the circuit.
      1. Turn the power switch off.
      2. Disconnect the cable from the negative (-) battery terminal.
        WARNING:

        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
    7. 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
    8. Check for a short in the circuit.
      1. Release the activation prevention mechanism built into connector B. Refer to DIAGNOSIS SYSTEM .
      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
        *6 Color: Orange

    NG → See step   5 

    OK: Go to next step 

  4. CHECK CENTER AIRBAG SENSOR ASSEMBLY 
    1. Restore the released activation prevention mechanism of connector B to the original condition.
      Fig 4: Checking Center Airbag Sensor Assembly
      GTY244467Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Connect the connectors to the steering pad and center airbag sensor assembly.
    3. Connect the cable to the negative (-) battery terminal.
    4. Turn the power switch on (IG), and wait for at least 60 seconds.
    5. Clear the DTCs stored in the memory. Refer to DTC CHECK / CLEAR .
    6. Turn the power switch off.
    7. Turn the power switch on (IG), and wait for at least 60 seconds.
    8. Check for DTCs. Refer to DTC CHECK / CLEAR .

      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 → See step   9 

    OK → See step   10 

  5. CHECK INSTRUMENT PANEL WIRE 
    1. Restore the released activation prevention mechanism of connector B to the original condition.
      Fig 5: Identifying L53 Connector Terminal
      GTY212081Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Disconnect the instrument panel wire from the spiral cable.
    3. 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
    4. Check for an open in the circuit.
      1. Turn the power switch off.
      2. Disconnect the cable from the negative (-) battery terminal.
        WARNING:

        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
    5. 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
    6. Check for a short in the circuit.
      1. Release the activation prevention mechanism built into connector B. Refer to DIAGNOSIS SYSTEM .
      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: Go to next step 

  6. CHECK SPIRAL CABLE 
    1. Check for a short to B+ in the circuit.
      Fig 6: Identifying z8 Connector Terminals
      GTY230797Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      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
    2. Check for an open in the circuit.
      1. Turn the power switch off.
      2. Disconnect the cable from the negative (-) battery terminal.
        WARNING:

        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
    3. 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
    4. Check for a short in the circuit.
      1. Release the activation prevention mechanism built into connector D. Refer to DIAGNOSIS SYSTEM .
      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
        *7 Color: Orange

    NG → See step   7 

    OK → See step   10 

  7. REPLACE SPIRAL CABLE. Refer to  REMOVAL 
  8. REPLACE STEERING PAD. Refer to  REMOVAL 
  9. REPLACE CENTER AIRBAG SENSOR ASSEMBLY. Refer to  REMOVAL 
  10. USE SIMULATION METHOD TO CHECK. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING 
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