Possible Causes
WARNING: This page is about a different car, the 2004 Mazda 3. However, it is still accessible from the selected car via links, so may be relevant.
Left seat belt buckle switch malfunction can be caused by poor connection between left seat belt buckle switch and SAS control module, open or short circuit in wiring harness between left seat belt buckle switch and SAS control module, left seat belt buckle switch malfunction or SAS control module malfunction.
- Inspect left seat belt buckle switch circuit
Using scan tool, inspect PID/DATA monitor DR-BUKL. See PID/DATA MONITOR & RECORD under DIAGNOSTICS. If PID readings are normal, replace SAS control module. See SAS CONTROL MODULE under REMOVAL & INSTALLATION. If readings are not normal, go to next step. - Inspect wiring harness between left seat belt buckle switch & ground
Turn ignition to LOCK position. Disable air bag system. See DISABLING SYSTEM under DISABLING & ACTIVATING AIR BAG SYSTEM. Disconnect left seat belt buckle switch connector. Measure between ground and left seat belt buckle switch connector terminal "B" for short to power or open. See Fig 1 . If short to power or open is detected, replace wiring harness. If wiring harness is okay, go to next step. - Inspect wiring harness between left seat belt buckle switch & SAS control module
Disconnect right and left front seat connectors. Disconnect right and left curtain air bag module connectors. Access SAS control module and disconnect connectors. See SAS CONTROL MODULE under REMOVAL & INSTALLATION. Measure for short to ground, short to power or open circuit between SAS control module connector No. 2, terminal No. 2W and left seat belt buckle switch connector terminal "A". See Figure & Fig 1 . If short to ground, short to power or open circuit is detected, replace wiring harness. If short to ground, short to power or open circuit is not detected, replace SAS control module.