B1771
SUPPLEMENTAL RESTRAINT SYSTEM: OCCUPANT CLASSIFICATION SYSTEM: B1771: Passenger Side Buckle Switch Circuit Malfunction
B1771 - Passenger Side Buckle Switch Circuit Malfunction
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.
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.
WIRING DIAGRAM
INSPECTION PROCEDURE
HINT
- If troubleshooting (wire harness inspection) is difficult to perform, remove the front passenger seat installation bolts to see under the seat cushion.
- In the above case, hold the seat so that it does not fall down. Hold the seat only as necessary because holding the seat for a long period of time may cause seat rail deformation.
PROCEDURE
1. CHECK CONNECTORS
(a) Turn the ignition switch off.
(b) Disconnect the negative (-) terminal cable from the battery.
(c) Check that the connectors are properly connected to the occupant classification ECU and the front seat inner belt assembly RH.
OK:
The connectors are properly connected.
HINT
If the connectors are not connected securely, reconnect the connectors and proceed to the next inspection.
(d) Disconnect the connectors from the occupant classification ECU and the front seat inner belt assembly RH.
(e) Check that the terminals of connectors are not damaged.
OK:
The terminals are not deformed or damaged.
NG -- REPLACE FRONT SEAT WIRE RH
OK -- Continue to next step.
2. CHECK FRONT SEAT WIRE RH (SHORT TO B+)
(a) Connect the negative (-) terminal cable to the battery.
(b) Turn the ignition switch on (IG).
(c) Measure the voltage according to the value(s) in the table below.
Standard voltage:
NG -- REPLACE FRONT SEAT WIRE RH
OK -- Continue to next step.
3. CHECK FRONT SEAT WIRE RH (OPEN)
(a) Turn the ignition switch off.
(b) Disconnect the negative (-) terminal cable from the battery.
(c) Using SST, connect terminals 2 and 1 of connector C.
NOTICE:
Do not forcibly insert SST into the terminals of the connector when connecting.
SST : 09843-18040
(d) Measure the resistance according to the value(s) in the table below.
Standard resistance:
NG -- REPLACE FRONT SEAT WIRE RH
OK -- Continue to next step.
4. CHECK FRONT SEAT WIRE RH (SHORT)
(a) Disconnect SST from connector C.
(b) Measure the resistance according to the value(s) in the table below.
Standard resistance:
NG -- REPLACE FRONT SEAT WIRE RH
OK -- Continue to next step.
5. CHECK FRONT SEAT WIRE RH (SHORT TO GROUND)
(a) Measure the resistance according to the value(s) in the table below.
Standard resistance:
NG -- REPLACE FRONT SEAT WIRE RH
OK -- Continue to next step.
6. CHECK DTC
(a) Connect the connectors to the occupant classification ECU and the front seat inner belt assembly RH.
(b) Connect the negative (-) terminal cable to the battery.
(c) Turn the ignition switch on (IG).
(d) Clear the DTCs stored in the occupant classification ECU Reading and Clearing Diagnostic Trouble Codes.
(e) Clear the DTCs stored in the center airbag sensor assembly DTC Check / Clear.
(f) Turn the ignition switch off.
(g) Turn the ignition switch on (IG).
(h) Check for DTCs Reading and Clearing Diagnostic Trouble Codes.
OK:
DTC B1771 is not output.
HINT
Codes other than DTC B1771 may be output at this time, but they are not related to this check.
NG -- REPLACE FRONT SEAT INNER BELT ASSEMBLY RH
OK -- USE SIMULATION METHOD TO CHECK Diagnosis System
7. REPLACE FRONT SEAT INNER BELT ASSEMBLY RH
(a) Turn the ignition switch off.
(b) Disconnect the negative (-) terminal cable from the battery.
(c) Replace the front seat inner belt assembly RH Removal.
HINT
Perform the inspection using parts from a normal vehicle if possible.
(d) Connect the negative (-) terminal cable to the battery.
(e) Turn the ignition switch on (IG).
(f) Clear the DTCs stored in the occupant classification ECU Reading and Clearing Diagnostic Trouble Codes.
(g) Clear the DTCs stored in the center airbag sensor assembly DTC Check / Clear.
(h) Turn the ignition switch off.
(i) Turn the ignition switch on (IG).
(j) Check for DTCs Reading and Clearing Diagnostic Trouble Codes.
OK:
DTC B1771 is not output.
HINT
Codes other than DTC B1771 may be output at this time, but they are not related to this check.
NG -- REPLACE OCCUPANT CLASSIFICATION ECU
OK -- END
8. REPLACE OCCUPANT CLASSIFICATION ECU
(a) Turn the ignition switch off.
(b) Disconnect the negative (-) terminal cable from the battery.
(c) Replace the occupant classification ECU Removal.
NEXT -- Continue to next step.
9. PERFORM ZERO POINT CALIBRATION
(a) Connect the negative (-) terminal cable to the battery.
(b) Connect Techstream to the DLC3.
(c) Turn the ignition switch on (IG).
(d) Using Techstream, perform "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 Techstream, perform "sensitivity check" Programming and Relearning.
Standard:
27 to 33 kg (59.52 to 72.75 lb)
NEXT -- END