DESCRIPTION
The passenger side buckle switch circuit consists of the occupant classification ECU and the front seat inner belt assembly RH.
DTC B1771 is recorded when a malfunction is detected in the passenger side buckle switch circuit.
Troubleshoot DTC B1771 first if DTCs B1771 and B1795 are output simultaneously.
| DTC No. | DTC Detection Condition | Trouble Area |
|---|---|---|
| B1771 | The occupant classification ECU receives a line short circuit signal, an open circuit signal, a short circuit to ground signal or a short circuit to B+ signal in the passenger side buckle switch circuit for 2 seconds. Passenger side buckle switch malfunction Occupant classification ECU malfunction | Front seat inner belt assembly RH (Passenger side buckle switch) Occupant classification ECU Front seat wire RH |
HINT
When DTC B1650/32 is detected as a result of troubleshooting for the AIRBAG SYSTEM, check the DTCs stored in the occupant classification ECU. When DTC B1771 in output, perform troubleshooting for the DTC.
Scheme 336
The front occupant classification sensor LH circuit consists of the occupant classification ECU and the front occupant classification sensor LH.
DTC B1780 is recorded when a malfunction is detected in the front occupant classification sensor LH circuit.
| DTC No. | DTC Detection Condition | Trouble Area |
|---|---|---|
| B1780 | The occupant classification ECU receives a line short circuit signal, an open circuit signal, a short circuit to ground signal or a short circuit to B+ signal in the front occupant classification sensor LH circuit for 2 seconds. Front occupant classification sensor LH malfunction Occupant classification ECU malfunction | Front seat frame with adjuster assembly RH (Front occupant classification sensor LH) Occupant classification ECU Front seat wire RH |
HINT
When DTC B1650/32 is detected as a result of troubleshooting for the AIRBAG SYSTEM, check the DTCs stored in the occupant classification ECU. When DTC B1780 in output, perform troubleshooting for the DTC.
Scheme 337
The front occupant classification sensor RH circuit consists of the occupant classification ECU and the front occupant classification sensor RH.
DTC B1781 is recorded when a malfunction is detected in the front occupant classification sensor RH circuit.
| DTC No. | DTC Detection Condition | Trouble Area |
|---|---|---|
| B1781 | The occupant classification ECU receives a line short circuit signal, an open circuit signal, a short circuit to ground signal or a short circuit to B+ signal in the front occupant classification sensor RH circuit for 2 seconds. Front occupant classification sensor RH malfunction Occupant classification ECU malfunction | Front seat frame with adjuster assembly RH (Front occupant classification sensor RH) Occupant classification ECU Front seat wire RH |
HINT
When DTC B1650/32 is detected as a result of troubleshooting for the AIRBAG SYSTEM, check the DTCs stored in the occupant classification ECU. When DTC B1781 in output, perform troubleshooting for the DTC.
Scheme 338
The rear occupant classification sensor LH circuit consists of the occupant classification ECU and the rear occupant classification sensor LH.
DTC B1782 is recorded when a malfunction is detected in the rear occupant classification sensor LH circuit.
| DTC No. | DTC Detection Condition | Trouble Area |
|---|---|---|
| B1782 | The occupant classification ECU receives a line short circuit signal, an open circuit signal, a short circuit to ground signal or a short circuit to B+ signal in the rear occupant classification sensor LH circuit for 2 seconds. Rear occupant classification sensor LH malfunction Occupant classification ECU malfunction | Front seat frame with adjuster assembly RH (Rear occupant classification sensor LH) Front seat wire RH Occupant classification ECU |
HINT
When DTC B1650/32 is detected as a result of troubleshooting for the AIRBAG SYSTEM, check the DTCs stored in the occupant classification ECU. When DTC B1782 in output, perform troubleshooting for the DTC.
Scheme 339
The rear occupant classification sensor RH circuit consists of the occupant classification ECU and the rear occupant classification sensor RH.
DTC B1783 is recorded when a malfunction is detected in the rear occupant classification sensor RH circuit.
| DTC No. | DTC Detecting Condition | Trouble Area |
|---|---|---|
| B1783 | The occupant classification ECU receives a line short circuit signal, an open circuit signal, a short circuit to ground signal or a short circuit to B+ signal in the rear occupant classification sensor RH circuit for 2 seconds. Rear occupant classification sensor RH malfunction. Occupant classification ECU malfunction. | Front seat frame with adjuster assembly RH (Rear occupant classification sensor RH) Occupant classification ECU Front seat wire RH |
HINT
When DTC B1650/32 is detected as a result of troubleshooting for the AIRBAG SYSTEM, check the DTCs stored in the occupant classification ECU. When DTC B1783 in output, perform troubleshooting for the DTC.
Scheme 340
DTC B1785 is output when the occupant classification ECU receives a collision detection signal sent by the front occupant classification sensor LH if an accident occurs.
DTC B1785 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 B1785 can be cleared by "zero point calibration" and "sensitivity check".
Therefore, if DTC B1785 is output, first perform "zero point calibration" and "sensitivity check".
| DTC No. | DTC Detection Condition | Trouble Area |
|---|---|---|
| B1785 | Front seat assembly RH malfunction Occupant classification ECU malfunction Front occupant classification sensor LH sensed large load | Front seat frame with adjuster assembly RH (Front occupant classification sensor LH) Occupant classification ECU |
HINT
When DTC B1650/32 is detected as a result of troubleshooting for the AIRBAG SYSTEM, check the DTCs stored in the occupant classification ECU. When DTC B1785 is output, perform troubleshooting for the DTC.
DTC B1786 is output when the occupant classification ECU receives a collision detection signal sent by the front occupant classification sensor RH if 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 "zero point calibration" and "sensitivity check".
Therefore, if DTC B1786 is output, first perform "zero point calibration" and "sensitivity check".
| DTC No. | DTC Detection Condition | Trouble Area |
|---|---|---|
| B1786 | Front seat assembly RH malfunction Occupant classification ECU malfunction Front occupant classification sensor RH sensed large load | Front seat frame with adjuster assembly RH (Front occupant classification sensor RH) Occupant classification ECU |
HINT
When DTC B1650/32 is detected as a result of troubleshooting for the AIRBAG SYSTEM, check the DTCs stored in the occupant classification ECU. When DTC B1786 is output, perform troubleshooting for the DTC.
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 Detection Condition | Trouble Area |
|---|---|---|
| B1787 | Front seat assembly RH malfunction Occupant classification ECU malfunction Rear occupant classification sensor LH sensed large load | Front seat frame with adjuster assembly RH (Rear occupant classification sensor LH) Occupant classification ECU |
HINT
When DTC B1650/32 is detected as a result of troubleshooting for the AIRBAG SYSTEM, check the DTCs stored in the occupant classification ECU. When DTC B1787 is output, perform troubleshooting for the DTC.
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 sensed large load | Front seat frame with adjuster assembly RH (Rear occupant classification sensor RH) Occupant classification ECU |
HINT
When DTC B1650/32 is detected as a result of troubleshooting for the AIRBAG SYSTEM, check the DTCs stored in the occupant classification ECU. When DTC B1788 is output, perform troubleshooting for the DTC.
The center airbag sensor assembly communication circuit consists of the occupant classification ECU and the center airbag sensor assembly.
DTC B1790 is recorded when a malfunction is detected in the center airbag sensor assembly communication circuit.
| DTC No. | DTC Detection Condition | Trouble Area |
|---|---|---|
| B1790 | The occupant classification ECU receives a line short circuit signal, an open circuit signal, a short circuit to ground signal or a short circuit to B+ signal in the center airbag sensor assembly communication circuit for 2 seconds. Center airbag sensor assembly malfunction Occupant classification ECU malfunction | Occupant classification ECU Center airbag sensor assembly Floor wire Front seat wire RH |
HINT
When DTC B1650/32 is detected as a result of troubleshooting for the AIRBAG SYSTEM, check the DTCs stored in the occupant classification ECU. When DTC B1790 is output, perform troubleshooting for the DTC.
Scheme 341
The occupant classification sensor power supply circuit consists of the occupant classification ECU and the occupant classification sensors.
DTC B1793 is recorded when a malfunction is detected in the occupant classification sensor power supply circuit.
| DTC No. | DTC Detection Condition | Trouble Area |
|---|---|---|
| B1793 | The occupant classification ECU receives a line short circuit signal, an open circuit signal, a short circuit to ground signal or a short circuit to B+ signal in the occupant classification sensor power supply circuit for 2 seconds. Occupant classification ECU malfunction | Front seat frame with adjuster assembly RH (Occupant classification sensors) Occupant classification ECU Front seat wire RH |
HINT
When DTC B1650/32 is detected as a result of troubleshooting for the AIRBAG SYSTEM, check the DTCs stored in the occupant classification ECU. When DTC B1793 is output, perform troubleshooting for the DTC.
Scheme 342
This circuit consists of the occupant classification ECU and the power source circuit (battery, fuse, and wire harness).
DTC B1794 is recorded when a malfunction is detected in the occupant classification ECU or the power source circuit.
HINT
If DTC B1794 is output after turning the ignition switch from off to on (IG) to off 50 times in a row when a malfunction occurs in the power circuit for the occupant classification system.
This DTC is output if a malfunction is detected even after being cleared unless the normal system code is input.
| DTC No. | DTC Detection Condition | Trouble Area |
|---|---|---|
| B1794 | The ignition switch is turned from off to on (IG), hold for 10 seconds or more, and turned off again 50 times in a row when a malfunction occurs in the power circuit for the occupant classification system. Occupant classification ECU malfunction | Battery ECU-B fuse Wire harness Occupant classification ECU |
When DTC B1650/32 is detected as a result of troubleshooting for the AIRBAG SYSTEM, check the DTCs stored in the occupant classification ECU. When DTC B1794 is output, perform troubleshooting for the DTC.
Scheme 343
Scheme 344
- CHECK BATTERY Measure the voltage of the battery. Standard voltage 11 to 14 V NG --> REPLACE BATTERY OK: Go to next step
- CHECK FUSE Measure the resistance of the ECU-B No. 1 fuse. Standard resistance Below 1 ohms NG --> REPLACE FUSE OK: Go to next step
- CHECK WIRE HARNESS (SOURCE VOLTAGE) Turn the ignition switch off. Disconnect the negative (-) terminal cable from the battery. Disconnect the connector from the occupant classification ECU. Connect the negative (-) terminal cable to the battery. Turn the ignition switch on (IG). Measure the voltage according to the value(s) in the table below. Standard voltage Tester Connection Switch Condition Specified Condition a3-1 (+B) - Body ground Always 11 to 14 V a3-7 (IG) - Body ground Ignition switch on (IG) 11 to 14 V Turn the ignition switch off. Measure the resistance according to the value(s) in the table below. Standard resistance Tester Connection Switch Condition Specified Condition a3-3 (GND) - Body ground Always Below 1 ohms NG --> REPLACE WIRE HARNESS OK: Go to next step
- CHECK DTC Turn the ignition switch off. Disconnect the negative (-) terminal cable from the battery. Connect the connector to the occupant classification ECU. Connect Techstream to the DLC3. Connect the negative (-) terminal cable to the battery. Turn the ignition switch on (IG). Clear the DTCs stored in the occupant classification ECU, refer to «DTC CHECK / CLEAR»(ref-422305-S07935282912011092600000). Clear the DTCs stored in the center airbag sensor assembly, refer to «DTC CHECK / CLEAR»(ref-422538-S33719463572011092600000). Turn the ignition switch off. Turn the ignition switch on (IG), and wait for at least 10 seconds. Check for DTCs, refer to «DTC CHECK / CLEAR»(ref-422305-S07935282912011092600000). OK DTC B1794 is not output. HINT: Codes other than DTC B1794 may be output at this time, but they are not related to this check. NG --> See step 5 OK --> See step 8
- REPLACE OCCUPANT CLASSIFICATION ECU Turn the ignition switch off. Disconnect the negative (-) terminal cable from the battery. Replace the occupant classification ECU, refer to «REMOVAL»(ref-422291-S35323662942011092600000). NEXT: Go to next step
- PERFORM ZERO POINT CALIBRATION Connect the negative (-) terminal cable to the battery. Connect Techstream to the DLC3. Turn the ignition switch on (IG). Using Techstream, perform "zero point calibration", refer to «INITIALIZATION»(ref-422305-S17263488592011092600000). OK "Zero Point Calibration is complete." is displayed. NEXT: Go to next step
- PERFORM SENSITIVITY CHECK Using Techstream, perform "sensitivity check", refer to «INITIALIZATION»(ref-422305-S17263488592011092600000). Standard 27 to 33 kg (59.52 to 72.75 lb) NEXT --> END
- USE SIMULATION METHOD TO CHECK. Refer to «DIAGNOSIS SYSTEM»(ref-422305-S41984707352011092600000)
DTC B1795 is recorded when a malfunction is detected in the occupant classification ECU.
Troubleshoot DTC B1771 first if DTCs B1771 and B1795 are output simultaneously.
| DTC No. | DTC Detection Condition | Trouble Area |
|---|---|---|
| B1795 | Front seat inner belt assembly RH malfunction Occupant classification ECU malfunction | Front seat inner belt assembly RH Occupant classification ECU |
HINT
When DTC B1650/32 is detected as a result of troubleshooting for the AIRBAG SYSTEM, check the DTCs stored in the occupant classification ECU. When DTC B1795 is output, perform troubleshooting for the DTC.
In sleep mode, the occupant classification ECU reads the condition of each sensor while the ignition switch is off.
In this mode, if occupant classification ECU detects an internal malfunction, DTC B1796 is output.
| DTC No. | DTC Detection Condition | Trouble Area |
|---|---|---|
| B1796 | Occupant classification ECU malfunction | Occupant classification ECU |
HINT
When DTC B1650/32 is detected as a result of troubleshooting for the AIRBAG SYSTEM, check the DTCs stored in the occupant classification ECU. When DTC B1796 is output, perform troubleshooting for the DTC.
The occupant classification system detects the front passenger seat condition. It then informs the front passenger airbag, front seat side airbag RH and front seat belt pretensioner RH condition (activated/not activated) with the passenger airbag ON/OFF indicator.
HINT
Approximately 6 seconds after the ignition switch is turned on (IG), the passenger airbag ON/OFF indicator will be ON/OFF depending on the conditions listed below.
| Front Passenger Seat Condition | Passenger Airbag ON/OFF Indicator | SRS Warning Light | |
|---|---|---|---|
| ON Indicator | OFF Indicator | ||
| Vacant | OFF | OFF | OFF |
| Adult is seated. | ON | OFF | OFF |
| Child is seated. | OFF | ON | OFF |
| Child restraint system is set. | OFF | ON | OFF |
| Occupant classification system failure | OFF | ON | ON |