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DTC 21-3x

DTC 21-3x (21-30 to 21-39, 21-3A to 21-3F): Short to Another Wire or Decreased Resistance in Driver's Seat Belt Tensioner

Special Tools Required
- SRS inflator simulator 07SAZ-T84011A
- SRS simulator lead C 07TAZ-SZ5011A

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 21-3x indicated?

YES - Go to step 3.

NO - Intermittent failure, system is OK at this time. Go to Troubleshooting Intermittent Failures. If another DTC is indicated, go to the DTC troubleshooting index.

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




4. Disconnect the driver's seat belt tensioner 2P connector from the SRS left side subharness (A).
5. Connect the SRS inflator simulator (2 Ohm connectors) and the simulator lead to the SRS left side subharness.
6. Reconnect the battery negative cable.
7. Erase the DTC memory.
8. Check for a DTC.

Is DTC 21-3x 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 battery negative cable, and wait for 3 minutes.




10. Disconnect the front passenger's seat belt tensioner connector (A).
11. Disconnect SRS unit connector B (28P) from the SRS unit.
12. Disconnect the special tool from the SRS left side subharness 2P connector.




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

Is the resistance as specified?

YES - Fault SRS unit; replace the SRS unit.

NO - Go to step 14.




14. Disconnect SRS left side subharness 28P connector C803 (A) from the SRS main subharness connector C803 (B).




15. Check resistance between the No.1 and No.2 terminals of the SRS left side subharness 28P connector C803. There should be an open circuit, or at least 1 MOhm.

Is the resistance as specified?

YES - Short in the SRS main subharness; replace the SRS main subharness.

NO - Short in the SRS left side subharness; replace the SRS left side subharness.