DTC 21-31

DTC 21-31: Short to Another Wire or Decreased Resistance in Driver's Seat Belt Tensioner

Special Tools Required
- SRS inflator simulator 07SAZ-TB4011A
- SRS simulator lead F 07XAZ- SZ30100

1. Erase the DTC memory.
2. Turn the ignition switch ON (II), and check that the SRS indicator comes on for about 6 seconds and then goes off.

Does the SRS indicator stay on, and is DTC 21-31 indicated?

YES - Go to step 3.

NO - Intermittent failure, system is OK at this time. Go to Troubleshooting Intermittent Failures. Initial Inspection and Diagnostic Overview If another DTC is indicated, go to the DTC Troubleshooting Index. Diagnostic Trouble Code Descriptions

3. Turn the ignition switch OFF. Disconnect the negative cable from the battery, and wait for 3 minutes.




4. Disconnect the left side wire harness 4P connector (A) from the driver's seat belt tensioner.
5. Connect the SRS inflator simulator (2 Ohms connectors) and simulator lead F to the left side wire harness.
6. Reconnect the negative cable to the battery.
7. Erase the DTC memory.
8. Read the DTC.

Is DTC 21-31 indicated?

YES - Go to step 9.

NO - Short in the driver's seat belt tensioner; replace the driver's seat belt

9. Turn the ignition switch OFF. Disconnect the negative cable from the battery, and wait for 3 minutes.
10. Disconnect the front passenger's seat belt tensioner connector).
11. Disconnect SRS unit connector B (28P) from the SRS unit.
12. Disconnect the simulator lead from the left side wire harness.




13. Check resistance between the No. 1 and the No. 2 terminals of SRS unit connector B (28P). There should be an open circuit or at least 1 KOhm.

Is the resistance as specified?

YES - Faulty SRS unit or poor connection at SRS unit connector B (28P) and the SRS unit. Check the connection; if the connection is OK, replace the SRS unit.

NO - Go to step 14.




14. Disconnect right side wire harness 16P connector C604 (A) from left side wire harness connector C604 (B).




15. Check resistance between the No. 3 [No. 4] and No. 4 [No. 5] terminals of the right side wire harness 16P connector C604. There should be an open circuit or at least 1 KOhm.
[] :'06 Model

Is the resistance as specified?

YES - Short in the left side wire harness; replace the left side wire harness

NO - Short in the right side wire harness; replace the right side wire harness.