DTC B1870/66: Short in Driver Side Front Seat Cushion Squib Circuit; DTC B1871/66: Open in Driver Side Front Seat Cushion Squib Circuit; DTC B1872/66: Short to GND in Driver Side Front Seat Cushion Squib Circuit; DTC B1873/66: Short to B+ in Driver Side Front Seat Cushion Squib Circuit: Procedure

1. Turn the ignition switch off.
2. Disconnect the cable from the negative (-) battery terminal, and wait for at least 90 seconds.
3. Check that the connector is properly connected to the SRS seat cushion airbag assembly LH.

   OK

   The connector is properly connected.

   HINT: 

   If the connector is not connected securely, reconnect the connector and proceed to the next inspection.

4. Disconnect the connector from the SRS seat cushion airbag assembly LH.
5. Check that the terminal of the connector is not damaged.

   OK

   The terminal is not deformed or damaged.

NG → REPLACE FLOOR WIRE 

OK: Go to next step 

• SST: 09843-18061 

Fig 1: Checking SRS Seat Cushion Airbag Assembly LH (Seat Cushion Squib LH)

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

1. Connect SST (resistance: 2.1 Ω) to connector C.
   WARNING:

   Never connect the tester to the SRS seat cushion airbag assembly LH (seat cushion squib LH) for measurement, as this may lead to a serious injury due to airbag deployment.

   NOTE:

   • Do not forcibly insert SST into the terminals of the connector when connecting SST.
   • Insert SST straight into the terminals of the connector.
2. Connect the cable to the negative battery terminal, and wait for at least 2 seconds.
3. Turn the ignition switch to ON, and wait for at least 60 seconds.
4. Clear the DTCs stored in the memory. Refer to DTC CHECK / CLEAR .
5. Turn the ignition switch off.
6. Turn the ignition switch to ON, and wait for at least 60 seconds.
7. Check for DTCs. Refer to DTC CHECK / CLEAR .

   OK

   DTC B1870, B1871, B1872, B1873 or 66 is not output.

   TEXT IN ILLUSTRATION
   
   

   *1	Seat Cushion Squib LH
   *2	Center Airbag Sensor Assembly
   *3	Connector C
   *a	Front view of wire harness connector (to Seat Cushion Squib LH)

   HINT: 

   DTCs other than B1870, B1871, B1872, B1873 and 66 may be output at this time, but they are not related to this check.

NG → See step   3 

OK → See step   6 

1. Turn the ignition switch off.
2. Disconnect the cable from the negative (-) battery terminal, and wait for at least 90 seconds.
3. Disconnect SST from connector C.
4. Check that the connector is properly connected to the center airbag sensor assembly.

   OK

   The connector is properly connected.

5. Disconnect the connector from the center airbag sensor assembly.
6. Check that the terminal of the connector is not damaged.

   OK

   The terminal is not deformed or damaged.

7. Check that the short spring for the floor wire connector with the activation prevention mechanism is not deformed or damaged.

   OK

   The short spring is not deformed or damaged.

NG → REPLACE FLOOR WIRE 

OK: Go to next step 

Fig 2: Checking Floor Wire (Seat Cushion Squib - Center Airbag Sensor Assembly)

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

1. Connect the cable to the negative battery terminal, and wait for at least 2 seconds.
2. Turn the ignition switch to ON.
3. Measure the voltage according to the value(s) in the table below.

   Standard Voltage

   Tester Connection	Switch Condition	Specified Condition
   G20-1 (FCD-) - Body ground	Ignition switch ON	Below 1 V
   G20-2 (FCD+) - Body ground	Ignition switch ON	Below 1 V

   TEXT IN ILLUSTRATION
   
   

   *1	Seat Cushion Squib LH
   *2	Floor Wire
   *3	Center Airbag Sensor Assembly
   *4	Connector C
   *a	Front view of wire harness connector (to Seat Cushion Squib LH)

4. Turn the ignition switch off.
5. Disconnect the cable from the negative (-) battery terminal, and wait for at least 90 seconds.
6. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   G20-1 (FCD-) - G20-2 (FCD+)	Always	Below 1 Ω

7. Release the activation prevention mechanism built into connector B. Refer to DIAGNOSIS SYSTEM .
8. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   G20-1 (FCD-) - G20-2 (FCD+)	Always	1 MΩ or higher
   G20-1 (FCD-) - Body ground	Always	1 MΩ or higher
   G20-2 (FCD+) - Body ground	Always	1 MΩ or higher

9. Restore the released activation prevention mechanism of connector B to the original condition.

NG → REPLACE FLOOR WIRE 

OK: Go to next step 

1. Connect the connectors to the SRS seat cushion airbag assembly LH and the center airbag sensor assembly.
2. Connect the cable to the negative battery terminal, and wait for at least 2 seconds.
3. Turn the ignition switch to ON, and wait for at least 60 seconds.
4. Clear the DTCs stored in the memory. Refer to DTC CHECK / CLEAR .
5. Turn the ignition switch off.
6. Turn the ignition switch to ON, and wait for at least 60 seconds.
7. Check for DTCs. Refer to DTC CHECK / CLEAR .

   OK

   DTC B1870, B1871, B1872, B1873 or 66 is not output.

   HINT: 

   DTCs other than B1870, B1871, B1872, B1873 and 66 may be output at this time, but they are not related to this check.

NG → See step   7 

OK → See step   8