Toyota RAV4 manuals

Toyota Sienna Service Manual: 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 occupant classification sensor RH if an accident occurs.

DTC B1788 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 B1788 can be cleared by "Zero point calibration" and "Sensitivity check".

Therefore, if DTC B1788 is output, first perform "Zero point calibration" and "Sensitivity check".

DTC No.

DTC Detection Condition

Trouble Area

B1788

  • Front seat assembly RH malfunction
  • Occupant classification ECU malfunction
  • Rear occupant classification sensor RH detected a large load
  • Front seat assembly RH (Rear occupant classification sensor RH)
  • 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 B1788 is not output. HINT: Codes other than DTC B1788 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 B1788 is not output. HINT: Codes other than DTC B1788 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 batter.
  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 "Zero point calibration" (28).

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

END

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 o ...

Center Airbag Sensor Assembly Communication Circuit Malfunction
DTC B1790 Center Airbag Sensor Assembly Communication Circuit Malfunction DESCRIPTION The center airbag sensor assembly communication circuit consists of the occupant classification ECU and the ...

Other materials:

Removal
HINT: Replace the RH side using the same procedures as for the LH side. 1. REMOVE FRONT WHEEL 2. REMOVE FRONT AXLE HUB LH NUT (See page DS- 5) 3. SEPARATE SPEED SENSOR FRONT LH (See page DS-5) 4. SEPARATE FRONT DISC BRAKE CALIPER ASSEMBLY LH (a) Remove the 2 bolts and separate the front ...

Manual Up / Down Function does not Operate on Rear LH Only
DESCRIPTION If the manual UP/DOWN function does not operate, the power window motor, the regulator switch or the wire harness may be malfunctioning. WIRING DIAGRAM INSPECTION PROCEDURE 1 CHECK WIRE HARNESS (POWER SOURCE) Disconnect the P38 regulator switch connector.  Turn ...

Installation
1. INSTALL CRANKSHAFT POSITION SENSOR  Apply a light coat of engine oil to the O-ring on the crankshaft position sensor.  Install the crankshaft position sensor with the bolt. Torque: 9.0 N*m (92 kgf*cm, 80 in.*lbf)  Connect the crankshaft position sensor connector. ...

В© 2011-2025 Copyright www.tsienna.net