DESCRIPTION
WIRING DIAGRAM
INSPECTION PROCEDURE
CHECK DTC OUTPUT (CAN COMMUNICATION SYSTEM)
CHECK DTC OUTPUT (SUPPLEMENTAL RESTRAINT SYSTEM)
READ VALUE OF INTELLIGENT TESTER
CHECK HARNESS AND CONNECTOR (SEAT BELT CONTROL ECU - FRONT SEAT BELT ASSEMBLY)
CHECK HARNESS AND CONNECTOR (SEAT BELT CONTROL ECU - FRONT SEAT INNER BELT ASSEMBLY)
CHECK HARNESS AND CONNECTOR (SEAT BELT CONTROL ECU - FRONT SEAT INNER BELT ASSEMBLY)
CHECK HARNESS AND CONNECTOR (SEAT BELT CONTROL ECU - FRONT SEAT INNER BELT ASSEMBLY)
CHECK DTC OUTPUT (PRE-CRASH SAFETY SYSTEM)
REPLACE FRONT SEAT INNER BELT ASSEMBLY (PASSENGER SIDE)
CHECK DTC OUTPUT (PRE-CRASH SAFETY SYSTEM)
DTC B2063 Buckle Switch Malfunction
DESCRIPTION
This circuit consists of the front seat inner belt assembly (driver side), front seat inner belt assembly passenger side), center airbag sensor assembly and seat belt control ECU.
When the driver side seat belt is fastened to the front seat inner belt assembly (driver side), the center airbag sensor assembly detects malfunctions in the circuit.
When the passenger side seat belt is fastened to the front seat inner belt assembly (passenger side), the seat belt control ECU detects malfunctions in the circuit.
The center airbag sensor assembly sends information about the seat belt fastened/unfastened condition and circuit malfunctions through CAN communication to the seat belt control ECU.
The seat belt control ECU uses information from the center airbag sensor assembly to control the pre-crash safety system.
| DTC No. | DTC Detection Condition | Trouble Area |
| B2063 | Open, short, +B short or body ground short between terminals of center airbag sensor assembly and front seat inner belt assembly LH
Open, short, +B short or body ground short between terminals of seat belt control ECU and front seat inner belt assembly RH
| Front seat inner belt assembly RH
Front seat inner belt assembly LH
Center airbag sensor assembly
Seat belt control ECU
|
WIRING DIAGRAM
INSPECTION PROCEDURE
- When the seat belt control ECU is replaced with a new one, INITIALIZATION must be performed .
| 1.CHECK DTC OUTPUT (CAN COMMUNICATION SYSTEM) |
Check that DTC U0151 is not output.
- OK:
- DTC U0151 is not output.
| | GO TO CAN COMMUNICATION SYSTEM |
|
|
| 2.CHECK DTC OUTPUT (SUPPLEMENTAL RESTRAINT SYSTEM) |
Check that DTC B1655 is not output.
- OK:
- DTC B1655 is not output.
| | GO TO SUPPLEMENTAL RESTRAINT SYSTEM |
|
|
| 3.READ VALUE OF INTELLIGENT TESTER |
Connect the intelligent tester to the DLC3.
Turn the engine switch on (IG) and the turn the intelligent tester main switch on.
Select P Bk SW in the Data List and read the value displayed on the intelligent tester.
| Item | Measurement Item/Range (Display) | Normal Condition | Diagnostic Note |
| P Bk SW | Buckle switch status of passenger's seat/
UNSET: Passenger side seat belt is unfastened
SET: Passenger side seat belt is fastened
NG: Indeterminate date | UNSET / SET | - |
- OK:
- SET (Passenger side seat belt is fastened) appears on the tester.
| | REPLACE SEAT BELT CONTROL ECU |
|
|
| 4.CHECK HARNESS AND CONNECTOR (SEAT BELT CONTROL ECU - FRONT SEAT BELT ASSEMBLY) |
Disconnect the negative (-) battery terminal and wait at least 90 seconds.
- Make sure that the engine switch is off before disconnecting the cable.
Disconnect the P4 (LHD) or O6 (RHD) belt and O38 ECU connectors.
Using a service wire, connect terminals PBK+ and PBK- of connector P4.
Measure the resistance according to the value(s) in the table below.
- Standard resistance:
| Tester Connection | Condition | Specified Condition |
| O38-14 (PBK+) - O38-12 (PBK-) | Always | Below 1 Ω |
| | REPAIR OR REPLACE HARNESS OR CONNECTOR |
|
|
| 5.CHECK HARNESS AND CONNECTOR (SEAT BELT CONTROL ECU - FRONT SEAT INNER BELT ASSEMBLY) |
Measure the resistance according to the value(s) in the table below.
- Standard resistance:
| Tester Connection | Condition | Specified Condition |
| O38-14 (PBK+) - Body ground | Always | 1kΩ or higher |
| O38-12 (PBK-) - Body ground | Always | 1kΩ or higher |
| | REPAIR OR REPLACE HARNESS OR CONNECTOR |
|
|
| 6.CHECK HARNESS AND CONNECTOR (SEAT BELT CONTROL ECU - FRONT SEAT INNER BELT ASSEMBLY) |
Measure the resistance according to the value(s) in the table below.
- Standard resistance:
| Tester Connection | Condition | Specified Condition |
| O38-14 (PBK+) - O38-12 (PBK-) | Always | 1 kΩ or higher |
| | REPAIR OR REPLACE HARNESS OR CONNECTOR |
|
|
| 7.CHECK HARNESS AND CONNECTOR (SEAT BELT CONTROL ECU - FRONT SEAT INNER BELT ASSEMBLY) |
Connect the negative (-) battery terminal, and turn the engine switch on (IG).
Measure the voltage according to the value(s) in the table below.
- Standard voltage:
| Tester Connection | Condition | Specified Condition |
| O38-14 (PBK+) - Body ground | Always | Below 1 V |
| O38-12 (PBK-) - Body ground | Always | Below 1 V |
| | REPAIR OR REPLACE HARNESS OR CONNECTOR |
|
|
| 8.CHECK DTC OUTPUT (PRE-CRASH SAFETY SYSTEM) |
Disconnect the negative (-) battery terminal and wait at least 90 seconds.
Connect the connectors from the seat belt control ECU and front seat inner belt assembly (passenger side).
Connect the cable to the negative (-) battery terminal and turn the engine switch on (IG). Then wait 60 seconds.
Recheck for DTC.
- OK:
- DTC B2063 is not output.
| | USE SIMULATION METHOD TO CHECK |
|
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| 9.REPLACE FRONT SEAT INNER BELT ASSEMBLY (PASSENGER SIDE) |
Disconnect the negative (-) battery terminal and wait at least 90 seconds.
Replace the front seat inner belt assembly of passenger side .
| 10.CHECK DTC OUTPUT (PRE-CRASH SAFETY SYSTEM) |
Connect the negative (-) battery terminal and turn the engine switch on (IG). Then wait 60 seconds.
Recheck for DTC.
- OK:
- DTC B2063 is not output.
| | REPLACE SEAT BELT CONTROL ECU |
|
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LEXUS IS250, IS220d / GSE20 ALE20
