DTC B15C4: Airbag Signal Malfunction/Not Input: Procedure

1. Turn the engine switch off.
2. Connect the Techstream to the DLC3.
3. Turn the engine switch on (IG) and wait for 10 seconds.
4. Turn the Techstream on.
5. Check the DTC of "Airbag System". Refer to DTC CHECK / CLEAR .

   Result

   Result	Proceed to
   DTC is not output	A
   DTC is output	B

B → See step   9 

A: Go to next step 

1. Remove the DCM (Telematics Transceiver) but do not disconnect the connectors. Refer to REMOVAL .
   Fig 1: Inspecting I135 DCM (Telematics Transceiver) Connector Terminals With Waveform

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Measure the voltage according to the value(s) in the table below.

   Standard Voltage

   Tester Connection	Switch Condition	Specified Condition
   I135-24 (GSW) - Body ground	Engine switch on (IG)	6.5 to 8.5 V

   TEXT IN ILLUSTRATION
   
   

   *a	Component with harness connected (DCM (Telematics Transceiver))

   REFERENCE WAVEFORM
   
   

   Item	Condition
   Tester connection	I135-24 (GSW) - Body ground
   Tool setting	5.0 V/DIV., 20 ms/DIV.
   Vehicle condition	Engine switch on (IG)

   Result

   Result	Proceed to
   8.5 V or higher	A
   Below 6.5 V	B
   6.5 to 8.5 V	C

B → See step   4 

C → See step   5 

A: Go to next step 

1. Remove the airbag sensor assembly but do not disconnect the connectors. Refer to REMOVAL .
2. w/ Airbag Sensor Assembly (for Built-in Type Yaw Rate Sensor)
   1. Measure the voltage according to the value(s) in the table below.
      Fig 2: Checking I47 Connector Terminals w/ Airbag Sensor Assembly (For Built-In Type Yaw Rate Sensor) With Waveform

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard Voltage

      Tester Connection	Switch Condition	Specified Condition
      I47-24 (GSW3) - Body ground	Engine switch on (IG)	8.5 V or higher

      TEXT IN ILLUSTRATION
      
      

      *a	Component with harness connected (Airbag Sensor Assembly)

      REFERENCE WAVEFORM
      
      

      Item	Condition
      Tester connection	I47-24 (GSW3) - Body ground
      Tool setting	5.0 V/DIV., 20 ms/DIV.
      Vehicle condition	Engine switch on (IG)

3. w/ Airbag Sensor Assembly (for Separate Type Yaw Rate Sensor)
   1. Measure the voltage according to the value(s) in the table below.
      Fig 3: Checking I47 Connector Terminals w/ Airbag Sensor Assembly (For Separate Type Yaw Rate Sensor) With Waveform

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard Voltage

      Tester Connection	Switch Condition	Specified Condition
      I47-24 (GSW3) - Body ground	Engine switch on (IG)	8.5 V or higher

      TEXT IN ILLUSTRATION
      
      

      *a	Component with harness connected (Airbag Sensor Assembly)

      REFERENCE WAVEFORM
      
      

      Item	Condition
      Tester connection	I47-24 (GSW3) - Body ground
      Tool setting	5.0 V/DIV., 20 ms/DIV.
      Vehicle condition	Engine switch on (IG)

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK → See step   7 

1. Disconnect the I135 DCM (Telematics Transceiver) connector.
2. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   I135-24 (GSW) - Body ground	Always	10 kΩ or higher

NG → See step   6 

OK: Go to next step 

1. Replace the DCM (Telematics Transceiver). Refer to REMOVAL .
   NOTE:

   • The engine switch must be off.
   • Do not swap the DCM (Telematics Transceiver) with one from another vehicle.

NEXT → See step   8 

1. Disconnect the I135 DCM (Telematics Transceiver) connector.
2. Disconnect the I47 airbag sensor assembly connector.
3. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   I135-24 (GSW) - I47-24 (GSW3)	Always	Below 1 Ω
   I135-24 (GSW) - Body ground	Always	10 kΩ or higher

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK → See step   7