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 pretensioner malfunction can be caused by open or short circuit in wiring harness between left seat belt pretensioner and SAS control module, left seat belt pretensioner malfunction or SAS control module malfunction.
- Inspect left seat belt pretensioner
Using scan tool, inspect resistance for PID/DATA monitor DR-PTENS. See PID/DATA MONITOR & RECORD under DIAGNOSTICS. If resistance is 1.5-3.1 ohms, replace SAS control module. See SAS CONTROL MODULE under REMOVAL & INSTALLATION. If resistance is 1.5-3.1 ohms and performing past malfunction diagnosis, test is complete. If resistance is not 1.5-3.1 ohms, go to next step. - Inspect left seat belt pretensioner connector
Turn ignition switch to LOCK position. Disable air bag system. See DISABLING SYSTEM under DISABLING & ACTIVATING AIR BAG SYSTEM. Access left seat belt pretensioner connector. See SEAT BELT BUCKLE PRETENSIONER & SWITCH ASSEMBLY under REMOVAL & INSTALLATION. Disconnect and inspect left seat belt pretensioner connector. If left seat belt pretensioner connector is damaged, replace wiring harness. If left seat belt pretensioner connector is not damaged, go to next step. - Isolate malfunction
Connect leads of 2 ohm resistor across terminals of left seat belt pretensioner 2-pin connector. Connect negative battery cable. Turn ignition switch to ON position. Retrieve Diagnostic Trouble Codes (DTCs). See RETRIEVING DIAGNOSTIC TROUBLE CODES (DTCS) under DIAGNOSTICS. If DTCs B1054, B1877, B1878, B1879 and/or B1885 are retrieved, replace air bag system wiring harness and go to next step. If DTCs B1054, B1877, B1878, B1879 and/or B1885 are not retrieved, replace right seat belt pretensioner. - Inspect SAS control module
Turn ignition switch to LOCK position. Disable air bag system. Connect left seat belt pretensioner connector. Connect negative battery cable. Retrieve DTCs. If DTCs B1054, B1877, B1878, B1879 and/or B1885 are retrieved, replace SAS control module. If DTCs B1054, B1877, B1878, B1879 and/or B1885 are not retrieved, test is complete.