71-21

SRS DTC Troubleshooting: 71-21

DTC 71-21: Short in the Driver's Seat Position Sensor

NOTE:

- Use the HDS to confirm the driver's seat position before proceeding with troubleshooting. Driver's Seat Position Sensor Operation Check

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

1. Clear the DTC memory. Reading and Clearing Diagnostic Trouble Codes

2. Turn the ignition switch to 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 71-21 indicated?
YES - Go to step 3.

NO - Intermittent failure, the system is OK at this time. Go to Troubleshooting Intermittent Failures. Reading and Clearing Diagnostic Trouble Codes If another DTC is indicated, troubleshoot the DTC.


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

4. Remove the rear inner cover. Front Seat Frame Removal/Installation

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

6. Reconnect the negative cable to the battery.

7. Clear the DTC memory.

8. Read the DTC. Reading and Clearing Diagnostic Trouble Codes

Is DTC 71-21 indicated?
YES - Go to step 9.

NO - Faulty driver's seat position sensor; replace the driver's seat position sensor, Service and Repair then clear the DTC.






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

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

11. Disconnect SRS unit connector B (28P) from the SRS unit. Service and Repair

12. 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 13.

NO - Short in the right side wire harness or left side wire harness; replace the faulty harness, then clear the DTC.






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

Is the resistance as specified?
YES - Faulty driver's seat position sensor or SRS unit; replace the driver's seat position sensor, Service and Repair then clear the DTC. If the problem is still present, replace the SRS unit. SRS Unit Replacement

NO - Short in the driver's seat wire harness, the right side wire harness, or the left side wire harness; replace the faulty harness, then clear the DTC.