- Occupant classification ECU receives collision detection signal, which is sent by front occupant classification sensor LH when accident occurs
- Front seat assembly RH is subjected to strong impact, even if actual accident has not occurred
| Last Modified: 04-05-2023 | 6.11:8.1.0 | Doc ID: RM100000000VJRW |
| Model Year Start: 2016 | Model: Sienna | Prod Date Range: [12/2015 - ] |
| Title: SUPPLEMENTAL RESTRAINT SYSTEMS: OCCUPANT CLASSIFICATION SYSTEM: B1785; Front Occupant Classification Sensor LH Collision Detection; 2016 - 2020 MY Sienna [12/2015 - ] | ||
|
DTC |
B1785 |
Front Occupant Classification Sensor LH Collision Detection |
DESCRIPTION
DTC B1785 is stored when the occupant classification ECU receives a collision detection signal, which is sent by the front occupant classification sensor LH when an accident occurs.
DTC B1785 is also stored when the front seat assembly RH is subjected to a strong impact, even if an actual accident has not occurred.
However, when the occupant classification ECU outputs a collision detection signal, even if the vehicle is not in a collision, DTC B1785 can be cleared by conducting the zero point calibration and sensitivity check.
Therefore, if DTC B1785 is stored, first perform the zero point calibration and sensitivity check.
|
DTC Code |
DTC Detection Condition |
Trouble Area |
|---|---|---|
|
B1785 |
Either of following conditions is met: |
Front seat cushion spring assembly RH (Front occupant classification sensor LH) |
HINT:
- When DTC B1650/32 is stored as a result of troubleshooting the airbag system, perform troubleshooting for DTC B1785 of the occupant classification system.
- Use the Techstream to check for DTCs of the occupant classification ECU, otherwise the DTCs cannot be read.
WIRING DIAGRAM
PROCEDURE
|
1. |
PERFORM ZERO POINT CALIBRATION |
(a) Connect the Techstream to the DLC3.
(b) Turn the ignition switch to ON, and wait for at least 60 seconds.
(c) Using the Techstream, perform the zero point calibration (See page
![2016 - 2020 MY Sienna [12/2015 - ]; SUPPLEMENTAL RESTRAINT SYSTEMS: OCCUPANT CLASSIFICATION SYSTEM: INITIALIZATION](/t3Portal/stylegraphics/info.gif)
).
| NG |
|
|
|
2. |
CHECK FOR DTC |
(a) Turn the ignition switch to ON, and wait for at least 60 seconds.
(b) Clear any DTCs stored in the memory (See page
).
HINT:
- First clear DTCs stored in the occupant classification ECU and then in the center airbag sensor assembly.
- Use the Techstream to clear the DTCs of the occupant classification ECU, otherwise the DTCs cannot be cleared.
(c) Turn the ignition switch off.
(d) Turn the ignition switch to ON, and wait for at least 60 seconds.
(e) Using the Techstream, check for DTCs of the occupant classification ECU (See page
).
OK:
DTC B1785 is not output.
HINT:
DTCs other than DTC B1785 may be output at this time, but they are not related to this check.
Result
|
Result |
Proceed to |
|---|---|
|
NG |
A |
|
OK |
B |
| B |
|
|
|
3. |
REPLACE FRONT SEAT CUSHION SPRING 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 cushion spring assembly RH.
-
for Manual seat (See page
).
-
for Power seat (See page
).
HINT:
Perform the inspection using parts from a normal vehicle when possible.
|
|
4. |
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, and wait for at least 60 seconds.
(d) Using the Techstream, perform the zero point calibration (See page
).
|
|
5. |
PERFORM SENSITIVITY CHECK |
(a) Using the Techstream, perform the sensitivity check (See page
).
Standard range:
27 to 33 kg (59.5 to 72.8 lb)
| NEXT |
|
END |
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