Diagnostic Procedure
- Remove ECU-B fuse and check continuity across fuse blades. ECU-B fuse is located in junction block at left kick panel. If fuse is faulty, replace fuse. Go to step 4. If fuse is okay, reinstall fuse and go to next step.
- Disable air bag system. See DISABLING SYSTEM under DISABLING & ACTIVATING AIR BAG SYSTEM. Reconnect negative battery cable. Turn ignition switch to ACC or ON position. Measure voltage between ground and harness side of air bag sensor assembly connector terminal No. 5 (circuit LA, Black-Yellow wire). See Fig 1. If 10-14 volts is not present, repair AIR BAG warning light bulb or circuit. See WIRING DIAGRAMS . If 10-14 volts is present, go to next step.
- Turn ignition switch to LOCK position. Disconnect negative battery cable. Reconnect air bag sensor assembly connector. Reconnect negative battery cable and wait at least 2 seconds. Turn ignition switch to ACC or ON position. If AIR BAG warning light operation is okay, system operation is normal. If AIR BAG warning light does not come on, check for poor connection at air bag sensor assembly connector terminal No. 5 (Black-Yellow wire). If connection is okay, replace air bag sensor assembly.
- Recheck ECU-B fuse. If fuse is blown, check harness between SRS fuse and AIR BAG warning light. If fuse is okay, check for intermittent fault. See AIR BAG WARNING LIGHT INTERMITTENT .
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