71-21

SRS DTC Troubleshooting: 71-21

DTC 71-21: Short in 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 and General Troubleshooting Information. Initial Inspection and Diagnostic Overview

- Before this troubleshooting, review Battery Terminal Disconnection and Reconnection. Procedures

1. Clear the DTC memory. Initial Inspection and Diagnostic Overview

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. Initial Inspection and Diagnostic Overview If another DTC is indicated, troubleshoot the DTC.


3. Turn the ignition switch to LOCK (0). Disconnect the negative cable from the battery, then wait at least 3 minutes.

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

5. Reconnect the negative cable to the battery.

6. Clear the DTC memory.

7. Read the DTC. Initial Inspection and Diagnostic Overview

Is DTC 71-21 indicated?
YES - Go to step 8.

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






8. Turn the ignition switch to LOCK (0). Disconnect the negative cable from the battery, then wait at least 3 minutes.

9. Disconnect both seat belt tensioner 4P connectors. Service and Repair

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

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

Is the resistance as specified?
YES - Go to step 12.

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






12. Measure the resistance between the No. 5 terminal of SRS unit connector B (28P) and body ground, and between the No. 6 terminal 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 If the problem is still present, replace the SRS unit. SRS Unit Replacement

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