B1786

SUPPLEMENTAL RESTRAINT SYSTEM: OCCUPANT CLASSIFICATION SYSTEM: B1786: Front Occupant Classification Sensor RH Collision Detection
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 occupant classification sensor RH when an accident occurs.

DTC B1786 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 B1786 can be cleared by performing the zero point calibration and sensitivity check.

Therefore, when DTC B1786 is output, first perform the zero point calibration and sensitivity check.





WIRING DIAGRAM





INSPECTION PROCEDURE

PROCEDURE

1. PERFORM ZERO POINT CALIBRATION

(a) Connect the Techstream to the DLC3.

(b) Turn the ignition switch to ON.

(c) Using the Techstream, perform the zero point calibration Programming and Relearning.

OK:

"Zero Point Calibration is complete." is displayed.

NG -- REPLACE FRONT SEAT ASSEMBLY RH
OK -- Continue to next step.

2. PERFORM SENSITIVITY CHECK

(a) Using the Techstream, perform the sensitivity check Programming and Relearning.

Standard value:

27 to 33 kg (59.52 to 72.75 lb)

NG -- REPLACE FRONT SEAT ASSEMBLY RH
OK -- Continue to next step.

3. CHECK FOR DTC

(a) Turn the ignition switch to ON.

(b) Clear the DTCs Reading and Clearing Diagnostic Trouble Codes.

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

(c) Turn the ignition switch off.

(d) Turn the ignition switch to ON.

(e) Check the DTCs Reading and Clearing Diagnostic Trouble Codes.

OK:

DTC B1786 is not output.

HINT
DTCs other than DTC B1786 may be output at this time, but they are not related to this check.

OK -- USE SIMULATION METHOD TO CHECK
NG -- Continue to next step.

4. REPLACE FRONT SEAT ASSEMBLY RH

(a) Turn the ignition switch off.

(b) Disconnect the cable from the negative (-) battery terminal, and wait for at least 90 seconds.

(c) Replace the front seat RH Components.

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

NEXT -- Continue to next step.

5. PERFORM ZERO POINT CALIBRATION

(a) Connect the cable to the negative (-) battery terminal, and wait for at least 2 seconds.

(b) Connect the Techstream to the DLC3.

(c) Turn the ignition switch to ON.

(d) Using the Techstream, perform the zero point calibration Programming and Relearning.

OK:

"Zero Point Calibration is complete." is displayed.

NG -- REPLACE OCCUPANT CLASSIFICATION ECU
OK -- Continue to next step.

6. PERFORM SENSITIVITY CHECK

(a) Using the Techstream, perform the sensitivity check Programming and Relearning.

Standard value:

27 to 33 kg (59.52 to 72.75 lb)

NG -- REPLACE OCCUPANT CLASSIFICATION ECU
OK -- Continue to next step.

7. CHECK FOR DTC

(a) Turn the ignition switch to ON.

(b) Clear the DTCs Reading and Clearing Diagnostic Trouble Codes.

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

(c) Turn the ignition switch off.

(d) Turn the ignition switch to ON.

(e) Check the DTCs Reading and Clearing Diagnostic Trouble Codes.

OK:

DTC B1786 is not output.

HINT
DTCs other than DTC B1786 may be output at this time, but they are not related to this check.

OK -- USE SIMULATION METHOD TO CHECK
NG -- Continue to next step.

8. REPLACE OCCUPANT CLASSIFICATION ECU

(a) Turn the ignition switch off.

(b) Disconnect the cable from the negative (-) battery terminal, and wait for at least 90 seconds.

(c) Replace the occupant classification ECU Components.

NEXT -- Continue to next step.

9. PERFORM ZERO POINT CALIBRATION

(a) Connect the cable to the negative (-) battery terminal, and wait for at least 2 seconds.

(b) Connect the Techstream to the DLC3.

(c) Turn the ignition switch to ON.

(d) Using the Techstream, perform the zero point calibration Programming and Relearning.

OK:

"Zero Point Calibration is complete." is displayed.

NEXT -- Continue to next step.

10. PERFORM SENSITIVITY CHECK

(a) Using the Techstream, perform the sensitivity check Programming and Relearning.

Standard value:

27 to 33 kg (59.52 to 72.75 lb)

NEXT -- END