DTC B1794: Open in Occupant Classification ECU Battery Positive Line: Procedure

1. Measure the voltage of the auxiliary battery.

   Standard Voltage

   11 to 14 V

NG → See step   7 

OK: Go to next step 

1. Turn the power switch off.
   Fig 1: Identifying W3 Wire Harness (Source Voltage) Connector Terminals

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Disconnect the cable from the negative (-) battery terminal.
3. Disconnect the connector from the occupant classification ECU.
4. Connect the cable to the negative (-) battery terminal.
5. Turn the power switch on (IG).
6. Measure the voltage according to the value(s) in the table below.

   Standard Voltage

   Tester Connection	Condition	Specified Condition
   W3-1 (+B) - Body ground	Always	11 to 14 V

7. Turn the power switch off.
8. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   W3-3 (GND) - Body ground	Always	Below 1 Ω

   TEXT IN ILLUSTRATION
   
   

   *1	Front view of wire harness connector (to Occupant Classification ECU)

NG → REPLACE WIRE HARNESS 

OK: Go to next step 

1. Turn the power switch off.
2. Disconnect the cable from the negative (-) battery terminal.
3. Connect the connector to the occupant classification ECU.
4. Connect the Techstream to the DLC3.
5. Connect the cable to the negative (-) battery terminal.
6. Turn the power switch on (IG).
7. Clear the DTCs stored in the occupant classification ECU. Refer toDTC CHECK / CLEAR .
8. Clear the DTCs stored in the center airbag sensor assembly. Refer toDTC CHECK / CLEAR .
9. Turn the power switch off.
10. Turn the power switch on (IG), and wait for at least 10 seconds.
11. Using the Techstream, check for DTCs of the occupant classification ECU. Refer toDTC CHECK / CLEAR .

    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   4 

OK → See step   8 

1. Turn the power switch off.
2. Disconnect the cable from the negative (-) battery terminal.
3. Replace the occupant classification ECU. Refer toREMOVAL .

NEXT: Go to next step 

1. Connect the cable to the negative (-) battery terminal.
2. Connect the Techstream to the DLC3.
3. Turn the power switch on (IG).
4. Using the Techstream, perform Zero Point Calibration. Refer toINITIALIZATION .

   OK

   "Zero Point Calibration is complete." is displayed.

NEXT: Go to next step 

1. Using the Techstream, perform Sensitivity Check. Refer toINITIALIZATION .

   Standard

   27 to 33 kg (59.5 to 72.8 lb)

NEXT → END