21-2x
SRS DTC Troubleshooting: 21-1x, 21-2x (x can be 0 thru 9 or A thru F)
DTC 21-1x ("x" can be 0 thru 9 or A thru F): Open in Driver's Seat Belt Tensioner
DTC 21-2x ("x" can be 0 thru 9 or A thru F): Increased Resistance in Driver's Seat Belt Tensioner
Special Tools Required
- SRS inflator simulator 07SAZ-TB4011A
- SRS simulator lead F 07XAZ-SZ30100
NOTE:
- 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 21-1x or 21-2x 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 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 F to the left side wire harness.
6. Reconnect the negative cable to the battery.
7. Clear the DTC memory.
8. Read the DTC. Initial Inspection and Diagnostic Overview
Is DTC 21-1x or 21-2x indicated?
YES - Go to step 9.
NO - Open or increased resistance in the driver's seat belt tensioner; replace the driver's seat belt. Front Seat Belt Replacement
9. Turn the ignition switch to LOCK (0). Disconnect the negative cable from the battery, then wait at least 3 minutes.
10. Disconnect the front passenger's seat belt tensioner connector. Service and Repair
11. Disconnect SRS unit connector B (28P) from the SRS unit. Service and Repair
12. Measure the resistance between the No. 1 and the No. 2 terminals of SRS unit connector B (28P). There should be 2.0-3.0 Ohms.
Is the resistance 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.. SRS Unit Replacement
NO - Go to step 13.
13. Disconnect right side wire harness 16P connector C604 (A) from left side wire harness connector C604 (B).
14. Measure the resistance between the No. 4 and No. 5 terminals of the left side wire harness 16P connector C604. There should be 2.0-3.0 Ohms.
Is the resistance as specified?
YES - Open or increased resistance in the right side wire harness; replace the right side wire harness.
NO - Open or increased resistance in the left side wire harness; replace the left side wire harness.