DESCRIPTION
DTC B1786 is set when the occupant detection ECU receives a collision detection signal, which is sent by the front occupant classification sensor RH when an accident occurs.
DTC B1786 is also set when the front seat with adjuster frame assembly RH is subjected to a strong impact, even if an actual accident has not occurred.
However, when the occupant detection ECU outputs a collision detection signal, even if the vehicle is not in a collision, DTC B1786 can be cleared by conducting the zero point calibration and sensitivity check.
Therefore, if DTC B1786 is set, first perform the zero point calibration and sensitivity check.
DTC No. |
DTC Detecting Conditions |
Trouble Areas |
---|---|---|
B1786 |
|
|
HINT:
WIRING DIAGRAM
(See page )
PROCEDURE
1. |
CHECK DTC |
(a) Turn the ignition switch to the ON position.
(b) Clear any DTCs stored in the airbag sensor assembly (See page
).
(c) Turn the ignition switch to the LOCK position.
(d) Turn the ignition switch to the ON position.
(e) Using the Techstream, check for DTCs of the occupant detection ECU (See page
).
OK:
DTC B1786 is not output.
HINT:
DTCs other than B1786 may be output at this time, but they are not related to this check.
OK | ![]() |
USE SIMULATION METHOD TO CHECK |
|
2. |
PERFORM ZERO POINT CALIBRATION |
(a) Connect the Techstream to the DLC3.
(b) Turn the ignition switch to the ON position.
(c) Using the Techstream, perform the zero point calibration (See page
).
OK:
"Zero Point Calibration is complete." is displayed on the Techstream.
NG | ![]() |
GO TO STEP 5 |
|
3. |
PERFORM SENSITIVITY CHECK |
(a) Using the Techstream, perform the sensitivity check (See page
).
Standard:
27 to 33 kg (59.52 to 72.75 lb)
NG | ![]() |
GO TO STEP 5 |
|
4. |
CHECK DTC |
(a) Turn the ignition switch to the ON position.
(b) Clear any DTCs stored in the airbag sensor assembly (See page
).
(c) Turn the ignition switch to the LOCK position.
(d) Turn the ignition switch to the ON position.
(e) Using the Techstream, check for DTCs of the occupant detection ECU (See page
).
OK:
DTC B1786 is not output.
HINT:
DTCs other than B1786 may be output at this time, but they are not related to this check.
NG | ![]() |
USE SIMULATION METHOD TO CHECK |
|
5. |
REPLACE FRONT SEAT WITH ADJUSTER FRAME ASSEMBLY RH |
(a) Turn the ignition switch to the LOCK position.
(b) Disconnect the negative (-) terminal cable from the battery, and wait for at least 90 seconds.
(c) Replace the front seat with adjuster frame assembly RH (See page
).
HINT:
Perform the inspection using parts from a normal vehicle when possible.
|
6. |
PERFORM ZERO POINT CALIBRATION |
(a) Connect the negative (-) terminal cable to the battery.
(b) Connect the Techstream to the DLC3.
(c) Turn the ignition switch to the ON position.
(d) Using the Techstream, perform the zero point calibration (See page
).
OK:
"Zero Point Calibration is complete." is displayed on the Techstream.
NG | ![]() |
GO TO STEP 9 |
|
7. |
PERFORM SENSITIVITY CHECK |
(a) Using the Techstream, perform the sensitivity check (See page
).
Standard:
27 to 33 kg (59.52 to 72.75 lb)
NG | ![]() |
GO TO STEP 9 |
|
8. |
CHECK DTC |
(a) Connect the connectors to the occupant detection ECU and the front occupant classification sensor RH.
(b) Connect the negative (-) terminal cable to the battery.
(c) Turn the ignition switch to the ON position.
(d) Clear any DTCs stored in the memory (See page
).
HINT:
(e) Turn the ignition switch to the LOCK position.
(f) Turn the ignition switch to the ON position.
(g) Using the Techstream, check for DTCs of the occupant detection ECU (See page
).
OK:
DTC B1786 is not output.
HINT:
DTCs other than B1786 may be output at this time, but they are not related to this check.
OK | ![]() |
USE SIMULATION METHOD TO CHECK |
|
9. |
REPLACE OCCUPANT DETECTION ECU |
(a) Turn the ignition switch to the LOCK position.
(b) Disconnect the negative (-) terminal cable from the battery, and wait for at least 90 seconds.
(c) Replace the occupant detection ECU (See page
).
|
10. |
PERFORM ZERO POINT CALIBRATION |
(a) Connect the negative (-) terminal cable to the battery.
(b) Connect the Techstream to the DLC3.
(c) Turn the ignition switch to the ON position.
(d) Using the Techstream, perform the zero point calibration (See page
).
OK:
"Zero Point Calibration is complete." is displayed on the Techstream.
|
11. |
PERFORM SENSITIVITY CHECK |
(a) Using the Techstream, perform the sensitivity check (See page
).
Standard :
27 to 33 kg (59.52 to 72.75 lb)
NEXT | ![]() |
USE SIMULATION METHOD TO CHECK |
System Diagram
SYSTEM DIAGRAM
Transmitting ECU (Transmitter)
Receiving ECU
Signal
Communication Method
4 wheel drive control ECU
Skid control ECU (Brake actuator assembly)
Rear differential lock status signal
H ...
Installation
INSTALLATION
PROCEDURE
1. INSTALL WINDSHIELD WIPER MOTOR ASSEMBLY
(a) Apply MP grease to the crank arm pivot of the windshield wiper motor
assembly.
Text in Illustration
*1
Crank Arm Pivot
...
Millimeter Wave Radar Sensor Communication Stop Mode
DESCRIPTION
Detection Item
Symptom
Trouble Area
Millimeter Wave Radar Sensor Communication Stop Mode
Either Condition is met:
Communication stop for "Front Radar" is indicated on the "Communication
Bus C ...