71-21

SRS DTC Troubleshooting: 71-21

DTC 71-21:

Short in the Driver's Seat Position Sensor

NOTE: Before doing this troubleshooting procedure, review SRS Precautions and Procedures Service and Repair, General Troubleshooting Information Reading and Clearing Diagnostic Trouble Codes.

1. Raise the driver's seat all the way up.

2. Clear the DTCs with the HDS.

3. Turn the ignition switch to ON (II), then wait for 10 seconds.

4. Check for DTCs with the HDS.

Is DTC 71-21 indicated?

YES -

Go to step 5.

NO -

Intermittent failure, the system is OK at this time. Go to Troubleshooting Intermittent Failures. If another DTC is indicated, troubleshoot the DTC. �

5. Turn the ignition switch to LOCK (0).

6. Remove the upper rail inner cover.

7. Disconnect the driver's seat wire harness 2P connector (A) from the driver's seat position sensor (B).





8. Clear the DTCs with the HDS.

9. Turn the ignition switch to ON (II), then wait for 10 seconds.

10. Check for DTCs with the HDS.

Is DTC 71-21 indicated?

YES -

Go to step 11.

NO -

Faulty driver's seat position sensor; replace the driver's seat position sensor Service and Repair, then clear the DTC.�

11. Turn the ignition switch to LOCK (0).

12. Disconnect the negative cable from the battery, then wait at least 3 minutes.

13. Disconnect SRS unit connector B (28P) from the SRS unit.

14. Measure the resistance between SRS unit connector B (28P) terminals No. 5 and No. 6. There should be an open circuit or at least 1 MOhms.





Is the resistance as specified?

YES -

Go to step 15.

NO -

Short to another wire in the SRS wire harness or the driver's seat wire harness; replace the faulty harness, then clear the DTC.�

15. Measure the resistance between body ground and SRS unit connector B (28P) terminals No. 5 and No. 6 individually. There should be an open circuit or at least 1 MOhms.





Is the resistance as specified?

YES -

Faulty driver's seat position sensor or the SRS unit; replace the driver's seat position sensor Service and Repair, then clear the DTC, and retest. If the DTC is still present, replace the SRS unit SRS Unit Replacement.�

NO -

Short to ground in the SRS wire harness or the drivers seat wire harness; replace the faulty harness, then clear the DTC.�