DTC B0021-1A: Decreased Resistance in the Left Side Curtain Airbag First Inflator (2018-19)
Special Tools Required:
SRS Short Canceller 070AZ-SAA0100
NOTE:
Before doing this troubleshooting procedure:
- Find out if the vehicle was in a collision. If so, verify that all the required components were replaced with new components of the correct part number, and that they were properly installed - Refer to: SRS Component Replacement/Inspection After Deployment .
- Review SRS Precautions and Procedures .
- Review General Troubleshooting Information
- Review information pertaining to 12 Volt Battery Terminal Disconnection and Reconnection
| DTC Description | DTC |
|---|---|
| B0021-1A Decreased resistance in the left side curtain airbag first inflator |
DTC (SRS)
- Problem verification
-1. Clear the DTCs with the HDS.
- 2. Turn the vehicle to the ON mode, then wait for 10 seconds.
- 3. Check for DTCs with the HDS.
DTC Description DTC B0021-1A Decreased resistance in the left side curtain airbag first inflator Is DTC B0021-1A indicated?
YES
The failure is duplicated. Go to step 2.
NO
Intermittent failure, the system is OK at this time. Go to Troubleshooting Intermittent Failures. If another DTC is indicated, troubleshoot the DTC.
- Left side curtain airbag inflator check
-1. Turn the vehicle to the OFF (LOCK) mode.
- 2. Disconnect the negative cable from the 12 volt battery, then wait at least 3 minutes.
- 3. Remove the headliner.
- 4. Disconnect the following connector.
Left side curtain airbag inflator 2P connector (on the right side wire harness) - 5. Reconnect the negative cable to the 12 volt battery.
- 6. Clear the DTCs with the HDS.
- 7. Turn the vehicle to the ON mode, then wait for 10 seconds.
- 8. Check for DTCs with the HDS.
DTC Description DTC B0021-1A Decreased resistance in the left side curtain airbag first inflator Is DTC B0021-1A indicated?
YES
Go to step 3.
NO
Faulty left side curtain airbag inflator; replace the left side curtain airbag , then clear the DTC.
- Shorted wire check (LCA1+ line to LCA1- line)
-1. Turn the vehicle to the OFF (LOCK) mode.
- 2. Disconnect the negative cable from the 12 volt battery, then wait at least 3 minutes.
- 3. Disconnect the following connector.
SRS unit connector B (39P) - 4. Connect the SRS short canceller to SRS unit connector B (39P) terminals No. 9 and No. 10.
- 5. Measure the resistance between test points 1 and 2.
Test condition Vehicle OFF (LOCK) mode Left side curtain airbag inflator 2P connector (on the right side wire harness): disconnected SRS unit connector B (39P): disconnected SRS unit connector B (39P) No. 9 and No. 10: connected to SRS short canceller Test point 1 SRS unit connector B (39P) No. 9 - Refer to: SRS Unit Connector for Inputs and Outputs Test point 2 SRS unit connector B (39P) No. 10 - Refer to: SRS Unit Connector for Inputs and Outputs Is there an open circuit, or at least 1 MΩ?
YES
The LCA1+ and LCA1- wires are OK. Check for any authorized service information related to the DTCs or symptoms you are troubleshooting or replace the SRS unit - Refer to: SRS Unit Removal and Installation .
NO
Short to another wire in the right side wire harness; replace the right side wire harness, then clear the DTC.