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 to DTC CHECK / CLEAR .
8. Clear the DTCs stored in the center airbag sensor assembly. Refer to DTC CHECK / CLEAR .
9. Turn the power switch off.
10. Turn the power switch on (IG), and wait for at least 10 seconds.
11. Check for DTCs. Refer to DTC 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 to REMOVAL .

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 to INITIALIZATION .

   OK

   "Zero Point Calibration is complete." is displayed.

NEXT: Go to next step 

1. Using the Techstream, perform Sensitivity Check. Refer to INITIALIZATION .

   Standard

   27 to 33 kg (59.5 to 72.8 lb)

NEXT → END