DTC Troubleshooting: 21-1x, 21-2x

DTC 21-1x (21-10 to 21-19, 21-1A to 21-1F): 
  
DTC 21-2x (21-20 to 21-29, 21-2A to 21-2F): 
  


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 21-1x or 21-2x indicated?


YES - Go to 3.


NO - Intermittent failure, system is OK at this time. Go to Troubleshooting Intermittent Failures. If another DTC is indicated, go to the DTC troubleshooting index for troubleshooting details.


3.Turn the ignition switch OFF. Disconnect the battery negative cable, and wait for 3 minutes.

4.Disconnect the left side seat belt tensioner 4P connector (A) from the floor wire harness.

5.Connect the SRS inflator simulator (2 W connectors) and the simulator lead to the floor wire harness.

6.Reconnect the battery negative cable.

7.Erase the DTC memory.

8.Read the DTC.

Is DTC 21-1x or 21-2x indicated?


YES - Go to 9.


NO - Open or increased resistance in the left side seat belt tensioner; replace the left side seat belt.n


9.Turn the ignition switch OFF. Disconnect the battery negative cable, and wait for 3 minutes.

10.Disconnect the right side seat belt tensioner 4P connector (A).

11.Disconnect SRS unit connector B (28P) from the SRS unit. Do not disconnect the special tool from floor wire harness.

12.Check resistance between the No. 1 terminal and the No. 2 terminal of SRS unit connector B (28P). There should be 2.0-3.0 W.

Is the resistance as specified?


YES - Faulty SRS unit or poor contact at SRS unit connector B (28P) and the SRS unit. Check the connection; if the connection is OK, replace the SRS unit.n


NO - Open or increased resistance in the floor wire harness; replace the floor wire harness.n