Toyota RAV4 manuals

Toyota Sienna Service Manual: Rear Occupant Classification Sensor LH Collision Detection

DTC B1787 Rear Occupant Classification Sensor LH Collision Detection

DESCRIPTION

DTC B1787 is output when the occupant classification ECU receives a collision detection signal sent by the rear occupant classification sensor LH if an accident occurs.

DTC B1787 is also output when the front seat assembly RH is subjected to a strong impact, even if an actual accident does not occur.

However, when the occupant classification ECU outputs a collision detection signal, even if the vehicle is not in a collision, DTC B1787 can be cleared by "Zero point calibration" and "Sensitivity check".

Therefore, if DTC B1787 is output, first perform "Zero point calibration" and "Sensitivity check".

DTC No.

DTC Detecting Condition

Trouble Area

B1787

  • Front seat assembly RH malfunction
  • Occupant classification ECU malfunction
  • Rear occupant classification sensor LH detected a large load
  • Front seat assembly RH (Rear occupant classification sensor LH)
  •  Occupant classification ECU

INSPECTION PROCEDURE

1 PERFORM ZERO POINT CALIBRATION

  1. Connect the intelligent tester to the DLC3.
  2.  Turn the ignition switch to the ON position.
  3.  Using the intelligent tester, perform "Zero point calibration" (28).

OK: "COMPLETED" is displayed

2 PERFORM SENSITIVITY CHECK

  1. Using the intelligent tester, perform "Sensitivity check" (28).

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

3 CHECK DTC

  1. Turn the ignition switch to the ON position.
  2. Clear the DTCs stored in the memory 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 (35).

OK: DTC B1787 is not output. HINT: Codes other than DTC B1787 may be output at this time, but they are not related to this check.

4 REPLACE FRONT SEAT ASSEMBLY RH

  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 front seat assembly RH ( for flat type, SE-48 for manual seat, SE-58 for power seat).

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

5 PERFORM ZERO POINT CALIBRATION

  1. Connect the negative (-) terminal cable to the battery.
  2.  Connect the intelligent tester to the DLC3.
  3.  Turn the ignition switch to the ON position.
  4.  Using the intelligent tester, perform "Zero point calibration" (28).

OK: "COMPLETED" is displayed

6 PERFORM SENSITIVITY CHECK

  1. Using the intelligent tester, perform "Sensitivity check" (28).

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

7 CHECK DTC

  1. Turn the ignition switch to the ON position.
  2.  Clear the DTCs stored in the memory.

    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 (35).

OK: DTC B1787 is not output. HINT: Codes other than DTC B1787 may be output at this time, but they are not related to this check.

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

9 PERFORM ZERO POINT CALIBRATION

  1. Connect the negative (-) terminal cable to the battery.
  2. Connect the intelligent tester to the DLC3.
  3.  Turn the ignition switch to the ON position.
  4. Using the intelligent tester, perform "Zero point calibration" (28).

OK: "COMPLETED" is displayed

10 PERFORM SENSITIVITY CHECK

  1. Using the intelligent tester, perform "Sensitivity check" (28).

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

END

Front Occupant Classification Sensor RH Collision Detection
DTC B1786 Front Occupant Classification Sensor RH Collision Detection DESCRIPTION DTC B1786 is output when the occupant classification ECU receives a collision detection signal sent by the front ...

Rear Occupant Classification Sensor RH Collision Detection
DTC B1788 Rear Occupant Classification Sensor RH Collision Detection DESCRIPTION DTC B1788 is output when the occupant classification ECU receives a collision detection signal sent by the rear o ...

Other materials:

Transponder Chip Malfunction
DTC B2793 Transponder Chip Malfunction DESCRIPTION This DTC is output when a malfunction is found in the key during the key code registration or the key code is not registered normally. Replace the key when the key code registration is not performed normally and this DTC is detected. IN ...

Installation
HINT:  Use the same procedures for the RH side and LH side.  The procedures listed below are for the LH side. 1. INSTALL SIDE AIRBAG SENSOR LH Check that the ignition switch is off.  Check that the battery negative (-) terminal is disconnected. CAUTION: Afte ...

Turning the high beam on/off manually
Switching to low beam Pull the lever to the original position. Switching to high beam Turn the light switch to the position. The Automatic High Beam can be operated when The engine switch is in the “ON” position (vehicles without a smart key system) or IGNITION ON mode (vehicl ...

© 2011-2025 Copyright www.tsienna.net