DTC B1771: Passenger Side Buckle Switch Circuit Malfunction: Procedure

1. Turn the engine switch on (IG), and wait for at least 60 seconds.
2. Clear the DTCs. Refer to DTC CHECK / CLEAR [12/2011 - ] .

   HINT: 

   First clear the DTCs stored in the occupant detection ECU, and then clear the DTCs stored in the center airbag sensor.

3. Turn the engine switch off.
4. Turn the engine switch on (IG), and wait for at least 60 seconds.
5. Check for DTCs. Refer to DTC CHECK / CLEAR [12/2011 - ] .

   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 → See step   2 

OK → See step   11 

1. Turn the engine switch off.
2. Disconnect the cable from the negative (-) battery terminal, and wait for at least 90 seconds.
3. Check that the connectors are properly connected to the occupant detection ECU.

   OK

   Connectors are properly connected.

NG → CONNECT CONNECTOR 

OK: Go to next step 

1. Disconnect the connectors from the occupant detection ECU.

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2. Check that the connectors are not damaged.

   OK

   Connectors are not deformed or damaged.

   TEXT IN ILLUSTRATION
   
   

   *1	Front Seat Inner Belt Assembly RH
   *2	Occupant Detection ECU

NG → See step   10 

OK: Go to next step 

1. Connect the connectors to the occupant detection ECU and front seat inner belt RH.
2. Connect the cable to the negative (-) battery terminal, and wait for at least 2 seconds.
3. Turn the engine switch on (IG), and wait for at least 60 seconds.
4. Clear the DTCs. Refer to DTC CHECK / CLEAR [12/2011 - ] .

   HINT: 

   First clear the DTCs stored in the occupant detection ECU, and then clear the DTCs stored in the center airbag sensor.

5. Turn the engine switch off.
6. Turn the engine switch on (IG), and wait for at least 60 seconds.
7. Check for DTCs. Refer to DTC CHECK / CLEAR [12/2011 - ] .

   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 → See step   5 

OK → See step   9 

1. Turn the engine switch off.
2. Disconnect the cable from the negative (-) battery terminal, and wait for at least 90 seconds.
3. Replace the front seat inner belt RH. Refer to REMOVAL [12/2011 - ] .

   HINT: 

   Perform the inspection using parts from a normal vehicle when possible.

4. Connect the cable to the negative (-) battery terminal, and wait for at least 2 seconds.
5. Turn the engine switch on (IG), and wait for at least 60 seconds.
6. Clear the DTCs. Refer to DTC CHECK / CLEAR [12/2011 - ] .

   HINT: 

   First clear the DTCs stored in the occupant detection ECU, and then clear the DTCs stored in the center airbag sensor.

7. Turn the engine switch off.
8. Turn the engine switch on (IG), and wait for at least 60 seconds.
9. Check for DTCs. Refer to DTC CHECK / CLEAR [12/2011 - ] .

   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 → See step   6 

OK → END (FRONT SEAT INNER BELT ASSEMBLY RH WAS DEFECTIVE) 

1. Turn the engine switch off.
2. Disconnect the cable from the negative (-) battery terminal, and wait for at least 90 seconds.
3. Replace the occupant detection ECU. Refer to DTC CHECK / CLEAR [12/2011 - ] .

   HINT: 

   Perform the inspection using parts from a normal vehicle when possible.

4. Connect the cable to the negative (-) battery terminal, and wait for at least 2 seconds.
5. Turn the engine switch on (IG), and wait for at least 60 seconds.
6. Clear the DTCs. Refer to DTC CHECK / CLEAR [12/2011 - ] .

   HINT: 

   If the DTCs are not cleared at this time, past DTCs will remain.

NEXT: Go to next step 

1. Perform the zero point calibration. Refer to INITIALIZATION [12/2011 - ] .

   OK

   "Zero Point Calibration is complete." is displayed.

NEXT: Go to next step 

1. Perform the sensitivity check. Refer to INITIALIZATION [12/2011 - ] .

   Standard

   27 to 33 kg (59.5 to 72.8 lb)

NEXT → END (OCCUPANT DETECTION ECU WAS DEFECTIVE)