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 W4 Connector Terminals

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Disconnect the cable from the negative (-) auxiliary battery terminal.
3. Disconnect the connector from the occupant detection ECU.
4. Connect the cable to the negative (-) auxiliary 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	Switch Condition	Specified Condition
   W4-1 (+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
   W4-3 (GND) - Body ground	Always	Below 1 Ω

   TEXT IN ILLUSTRATION
   
   

   *a	Front view of wire harness connector (to Occupant Detection ECU)

NG → REPLACE WIRE HARNESS 

OK: Go to next step 

1. Turn the power switch off.
2. Disconnect the cable from the negative (-) auxiliary battery terminal.
3. Connect the connector to the occupant detection ECU.
4. Connect the cable to the negative (-) auxiliary battery terminal.
5. Turn the power switch on (IG).
6. Clear the DTCs stored in the occupant detection ECU. Refer to DTC CHECK / CLEAR .
7. Clear the DTCs stored in the airbag sensor assembly. Refer to DTC CHECK / CLEAR .
8. Turn the power switch off.
9. Turn the power switch on (IG), and wait for at least 10 seconds.
10. 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 (-) auxiliary battery terminal.
3. Replace the occupant detection ECU. Refer to REMOVAL .

NEXT: Go to next step 

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

NEXT: Go to next step 

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

NEXT → END