LEMON Manuals: Even more car manuals for everyone
Home >> Toyota >> 2008 >> FJ Cruiser RWD >> Repair and Diagnosis >> External Pages >> Different car >> Section 194 (Supplemental Restraint System) >> Occupant Classification System >> DTC B1790 Center Airbag Sensor Assembly Communication Circuit Malfunction >> Inspection Procedure

Inspection Procedure

WARNING: This page is about a different car, the 2008 Toyota Yaris. However, it is still accessible from the selected car via links, so may be relevant.

HINT:

  1. CHECK DTC 
    1. Turn the ignition switch to the on position.
    2. Clear the DTCs stored in the memory (See DTC CHECK/CLEAR  ).

      HINT:

      First clear DTCs stored in the occupant classification ECU and then in the center airbag sensor assembly.

    3. Turn the ignition switch to the lock position.
    4. Turn the ignition switch to the on position.
    5. Check the DTCs (See DTC CHECK/CLEAR  ).

      OK: DTC B1790 is not output. 

      HINT:

      Codes other than DTC B1790 may be output at this time, but they are not related to this check.

    OK: USE SIMULATION METHOD TO CHECK 

    NG: GO TO NEXT STEP 

  2. CHECK CONNECTION OF CONNECTORS 
    1. Turn the ignition switch to the lock position.
    2. Disconnect the negative (-) terminal cable from the battery and wait for at least 90 seconds.
    3. Check that the connectors are properly connected to the occupant classification ECU and the center airbag sensor assembly.

      OK: The connectors are properly connected. 

    NG: CONNECT CONNECTORS 

    OK: GO TO NEXT STEP 

  3. CHECK FLOOR WIRE (TO B+) 
    1. Disconnect the connectors from the occupant classification ECU and the center airbag sensor assembly.
    2. Connect the negative (-) terminal cable to the battery.
    3. Turn the ignition switch to the on position.
    4. Measure the voltage.

      Standard voltage 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester connection Condition Specified condition
      J24-8 (FSR+) - Body ground Ignition switch on Below 1 V
      J24-4 (FSR-) - Body ground Ignition switch on Below 1 V
    5. Fig 1: Checking Floor Wire (To B+)
      G04830194Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE FLOOR WIRE 

    OK: GO TO NEXT STEP 

  4. CHECK FLOOR WIRE (FOR OPEN) 
    1. Turn the ignition switch to the lock position.
    2. Disconnect the negative (-) terminal cable from the battery and wait for at least 90 seconds.
    3. Using a service wire, connect J9-12 (FSP+) and J9-13 (FSP-) of connector B.
      NOTE: Do not forcibly insert the service wire into the terminals of the connector when connecting.
    4. Measure the resistance.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester connection Condition Specified condition
      J24-8 (FSR+) -J24-4 (FSR-) Always Below 1 Ω
    5. Fig 2: Checking Floor Wire (For Open)
      G04830195Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE FLOOR WIRE 

    OK: GO TO NEXT STEP 

  5. CHECK FLOOR WIRE (FOR SHORT) 
    1. Disconnect the service wire from connector B.
    2. Measure the resistance.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester connection Condition Specified condition
      J24-8 (FSR+) -J24-4 (FSR-) Always 1 MΩ or higher
    3. Fig 3: Checking Floor Wire (To B+)
      G04830194Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE FLOOR WIRE 

    OK: GO TO NEXT STEP 

  6. CHECK FLOOR WIRE (TO GROUND) 
    1. Measure the resistance.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester connection Condition Specified condition
      J24-8 (FSR+) - Body ground Always 1 MΩ or higher
      J24-4 (FSR-) - Body ground Always 1 MΩ or higher
    2. Fig 4: Checking Floor Wire (To B+)
      G04830194Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE FLOOR WIRE 

    OK: GO TO NEXT STEP 

  7. CHECK DTC 
    1. Connect the connectors to the occupant classification ECU and the center airbag sensor assembly.
    2. Connect the negative (-) terminal cable to the battery.
    3. Turn the ignition switch to the on position.
    4. Clear the DTCs stored in the memory (See DTC CHECK/CLEAR  ).

      HINT:

      First clear DTCs stored in the occupant classification ECU and then in the center airbag sensor assembly.

    5. Turn the ignition switch to the lock position.
    6. Turn the ignition switch to the on position.
    7. Check the DTCs (See DTC CHECK/CLEAR  ).

      OK: DTC B1790 is not output. 

      HINT:

      Codes other than DTC B1790 may be output at this time, but they are not related to this check.

    OK: USE SIMULATION METHOD TO CHECK 

    NG: GO TO NEXT STEP 

  8. REPLACE OCCUPANT CLASSIFICATION ECU 
    1. Turn the ignition switch to the lock position.
    2. Disconnect the negative (-) terminal cable from the battery and wait for at least 90 seconds.
    3. Replace the occupant classification ECU (See ON-VEHICLE INSPECTION  ).

      HINT:

      Perform the inspection using parts from a normal vehicle if possible.

  9. PERFORM ZERO POINT CALIBRATION 
    1. Connect the negative (-) terminal cable to the battery.
    2. Connect the Techstream to the DLC3.
    3. Turn the ignition switch to the on position.
    4. Using the Techstream, perform the zero point calibration (See INITIALIZATION  ).

      OK: COMPLETED is displayed. 

  10. PERFORM SENSITIVITY CHECK 
    1. Using the Techstream, perform the sensitivity check (See INITIALIZATION  ).
      1. Confirm that nothing is placed on the passenger seat.
      2. Confirm that the beginning sensor reading is within the standard range.

        Standard range: -3.2 to 3.2 kg (-7 to 7 lb) 

      3. Place a 30 kg (66.14 lb) weight (e.g. a lead mass) onto the front passenger seat.
      4. Confirm that the sensitivity is within the standard range.

        Standard range: 27 to 33 kg (59.52 to 72.75 lb) 

        HINT:

        When performing the sensitivity check, use a solid metal weight (the check result may not be accurate if a liquid weight is used).

  11. CHECK DTC 
    1. Turn the ignition switch to the on position.
    2. Clear the DTCs stored in the memory (See DTC CHECK/CLEAR  ).

      HINT:

      First clear DTCs stored in the occupant classification ECU and then in the center airbag sensor assembly.

    3. Turn the ignition switch to the lock position.
    4. Turn the ignition switch to the on position.
    5. Check the DTCs (See DTC CHECK/CLEAR  ).

      OK: DTC B1790 is not output. 

      HINT:

      Codes other than DTC B1790 may be output at this time, but they are not related to this check.

    NG: REPLACE CENTER AIRBAG SENSOR ASSEMBLY 

    OK: END