DTC U3000-49
DTC U3000-49 : Internal Failure of the SRS Unit
- Before doing this troubleshooting procedure, review SRS Precautions and Procedures , General Troubleshooting Information , and Battery Terminal Disconnection and Reconnection - Refer to: Battery Terminal Disconnection and Reconnection .
| DTC Description | DTC |
|---|---|
| U3000-49 Internal failure of the SRS unit |
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 U3000-49 Internal failure of the SRS unit Is DTC U3000-49 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.
- Shorted wire check (SWSP line to power)
-1. Turn the vehicle to the OFF (LOCK) mode.
- 2. Disconnect the negative cable from the battery, then wait at least 3 minutes.
- 3. Disconnect the following connectors.
SRS unit connector B (39P) Front passenger's weight sensor (front inner side) 3P connector (on the front passenger's seat wire harness) Front passenger's weight sensor (rear inner side) 3P connector (on the front passenger's seat wire harness) Front passenger's weight sensor (front outer side) 3P connector (on the front passenger's seat wire harness) Front passenger's weight sensor (rear outer side) 3P connector (on the front passenger's seat wire harness) - 4. Reconnect the negative cable to the battery.
- 5. Turn the vehicle to the ON mode.
- 6. Measure the voltage between test points 1 and 2.
Test condition Vehicle ON mode SRS unit connector B (39P): disconnected Front passenger's weight sensor (front inner side) 3P connector (on the front passenger's seat wire harness): disconnected Front passenger's weight sensor (rear inner side) 3P connector (on the front passenger's seat wire harness): disconnected Front passenger's weight sensor (front outer side) 3P connector (on the front passenger's seat wire harness): disconnected Front passenger's weight sensor (rear outer side) 3P connector (on the front passenger's seat wire harness): disconnected Test point 1 SRS unit connector B (39P) No. 26 - Refer to: SRS Unit Connector for Inputs and Outputs (2017 2018 2019 2020) Test point 2 Body ground Is there 0.2 V or less?
YES
The SWSP wire is not shorted to power. Go to step 3.
NO
Short to power in the floor wire harness or the front passenger's seat wire harness; replace the faulty harness, then clear the DTC.
- Shorted wire check (SWSP line)
-1. Turn the vehicle to the OFF (LOCK) mode.
- 2. Disconnect the negative cable from the battery, then wait at least 3 minutes.
- 3. Measure the resistance between test points 1 and 2.
Test condition Vehicle OFF (LOCK) mode SRS unit connector B (39P): disconnected Front passenger's weight sensor (front inner side) 3P connector (on the front passenger's seat wire harness): disconnected Front passenger's weight sensor (rear inner side) 3P connector (on the front passenger's seat wire harness): disconnected Front passenger's weight sensor (front outer side) 3P connector (on the front passenger's seat wire harness): disconnected Front passenger's weight sensor (rear outer side) 3P connector (on the front passenger's seat wire harness): disconnected Test point 1 SRS unit connector B (39P) No. 26 - Refer to: SRS Unit Connector for Inputs and Outputs (2017 2018 2019 2020), Test point 2 Body ground Is there an open circuit, or at least 1 MΩ?
YES
The SWSP wire is not shorted. Go to step 4.
NO
Short to ground in the floor wire harness or the front passenger's seat wire harness; replace the faulty harness, then clear the DTC.
- Shorted wire check (SWSP line to SWSG line)
-1. Measure the resistance between test points 1 and 2.
Test condition Vehicle OFF (LOCK) mode SRS unit connector B (39P): disconnected Front passenger's weight sensor (front inner side) 3P connector (on the front passenger's seat wire harness): disconnected Front passenger's weight sensor (rear inner side) 3P connector (on the front passenger's seat wire harness): disconnected Front passenger's weight sensor (front outer side) 3P connector (on the front passenger's seat wire harness): disconnected Front passenger's weight sensor (rear outer side) 3P connector (on the front passenger's seat wire harness): disconnected Test point 1 SRS unit connector B (39P) No. 26 - Refer to: SRS Unit Connector for Inputs and Outputs (2017 2018 2019 2020) Test point 2 SRS unit connector B (39P) No. 28 - Refer to: SRS Unit Connector for Inputs and Outputs (2017 2018 2019 2020), Is there an open circuit, or at least 1 MΩ?
YES
Go to step 5.
NO
Short to another wire in the floor wire harness or the front passenger's seat wire harness; replace the faulty harness, then clear the DTC.
- Front passenger's weight sensor check
-1. Substitute a known-good front passenger's weight sensors as an assembly.
- 2. Reconnect the following connectors.
SRS unit connector B (39P) Front passenger's weight sensor (front inner side) 3P connector (on the front passenger's seat wire harness) Front passenger's weight sensor (rear inner side) 3P connector (on the front passenger's seat wire harness) Front passenger's weight sensor (front outer side) 3P connector (on the front passenger's seat wire harness) Front passenger's weight sensor (rear outer side) 3P connector (on the front passenger's seat wire harness) - 3. Reconnect the negative cable to the 12 volt battery.
- 4. Clear the DTCs with the HDS.
- 5. Turn the vehicle to the ON mode, then wait for 10 seconds.
- 6. Check for DTCs with the HDS.
DTC Description DTC U3000-49 Internal failure of the SRS unit Is DTC U3000-49 indicated?
YES
The front passenger's weight sensor is OK. Faulty SRS unit or poor connection at SRS unit connector B (39P) and the SRS unit. Check the connection; if the connection is 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 (2017 2018 2019 2020), .
NO
Faulty front passenger's weight sensor. Replace the front passenger's weight sensors as an assembly - Refer to: Front Passenger's Weight Sensor Removal and Installation (2017 2018 2019 2020), .