DTC 21-81

DTC 21-81: Short to Power 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 21-81 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 P 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 21-81 indicated?

YES - Go to step 9.

NO - Short to power 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. Reconnect the negative cable to the battery.
14. Turn the ignition switch ON (II).




15. Check for voltage between the No. 1 terminal of SRS unit connector B (28P) and body ground, and between the No. 2 terminal and body ground. There should be 0.5 V or less.

Is the voltage 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 16.




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




17. Check for voltage between the No. 3 [No. 4] terminal of the right side wire harness 16P connector C604 and body ground, and between the No. 4 [No. 5] terminal and body ground. There should be 0.5 V or less.
[]: 06 Model

Is the voltage as specified?

YES - Short to power in the left side wire harness; replace the left side wire harness.

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