DTC B15C4-64: Airbag Signal Signal Plausibility Failure [10/2019 - 10/2022]: Procedure

1. Turn the ignition switch off.
2. Connect the Techstream to the DLC3.
3. Turn the ignition switch to ON and wait for 10 seconds or more.
4. Turn the Techstream on.
5. Clear the DTCs.

   Refer to DTC CHECK / CLEAR [11/2018 - 08/2020] , or refer to DTC CHECK / CLEAR [08/2020 - ]

6. Check for DTCs and check that no DTCs are output.

   OK

   No DTCs are output.

   Result

   Proceed to
   OK
   NG

Result: 

NG 

GO TO AIRBAG SYSTEM. Refer to  DIAGNOSTIC TROUBLE CODE CHART [02/2019 - 08/2020]  , or refer to  DIAGNOSTIC TROUBLE CODE CHART [08/2020 - ] 

Result: 

OK 

See step  2

1. Turn the ignition switch off.
2. Connect the Techstream to the DLC3.
3. Turn the ignition switch to ON and wait for 10 seconds or more.
4. Turn the Techstream on.
5. Clear the DTCs.

   Refer to DTC CHECK / CLEAR [10/2019 - 10/2022]

   Body Electrical > Telematics > Clear DTCs 

6. Check for DTCs and check that no DTCs are output.

   Refer to DTC CHECK / CLEAR [10/2019 - 10/2022]

   Body Electrical > Telematics > Trouble Codes 

   OK

   No DTCs are output.

   Result

   Proceed to
   OK
   NG

Result: 

OK 

USE SIMULATION METHOD TO CHECK. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [11/2018 - ] 

Result: 

NG 

See step  3

1. Remove the DCM (telephone transceiver assembly) but do not disconnect the connectors.

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   *a	Component with harness connected (DCM [Telephone Transceiver Assembly])

   Refer to REMOVAL [10/2019 - 10/2022]

2. Check the input waveform.
   1. Check the signal waveform according to the condition(s) in the table below. (Check the waveform from the back of the wire harness connector of the DCM (telephone transceiver assembly) while the airbag ECU assembly connectors are connected.)

      Reference Waveform

      Item	Condition
      Tester connection	G131-13 (GSW) - Body ground
      Tool setting	5.0 V/DIV., 20 ms/DIV.
      Vehicle condition	Ignition switch ON

      OK

      The waveform is similar to that shown in the illustration.

   Result

   Proceed to
   OK
   NG

Result: 

NG 

See step  5

Result: 

OK 

See step  4

1. Replace the DCM (telephone transceiver assembly) with a new one.

   Refer to REMOVAL [10/2019 - 10/2022]

   NOTE:

   • The ignition switch must be off.
   • Do not exchange the DCM (telephone transceiver assembly) with one from another vehicle.

   Result

   Proceed to
   NEXT

Result: 

NEXT 

PERFORM DCM ACTIVATION. Refer to  DCM ACTIVATION [10/2019 - 10/2022] 

1. Disconnect the G131 DCM (telephone transceiver assembly) connector.
2. Disconnect the G70 airbag ECU assembly connector.
3. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   G131-13 (GSW) - G70-23 (GSW3)	Always	Below 1 Ω
   G131-13 (GSW) - Body ground	Always	10 kΩ or higher

   Result

   Proceed to
   OK
   NG

Result: 

OK 

REPLACE AIRBAG ECU ASSEMBLY. Refer to  REMOVAL [10/2019 - 08/2020]  , or refer to  REMOVAL [08/2020 - 12/2021]  , or refer to  REMOVAL [12/2021 - 10/2022] 

Result: 

NG 

REPLACE HARNESS OR CONNECTOR