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Home >> Mazda >> 1996 >> B3000 Base, Standard >> Repair and Diagnosis >> External Pages >> Different car >> Section 249 (Air Bag Restraint System) >> Diagnostic Tests >> Code 53 - Diagnostic Monitor Internal Fault >> Possible Causes
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Possible Causes

WARNING: This page is about a different car, the 1995 Ford Pickup, 1995 Ford F-Super Duty, 1995 Ford Cab & Chassis, and 1995 Ford Bronco. However, it is still accessible from the selected car via links, so may be relevant.

Internal diagnostic monitor self-test failure.

  1. Verify Condition  - Turn ignition on. Check for fault codes. If Code 53 is flashing, go to step 2). If Code 53 is not flashing, check connectors, wiring and crimps for an intermittent problem. DO NOT  proceed with diagnostic test unless code is flashing. Doing so will result in needless replacement of system components.
  2. Deactivate System  - Deactivate air bag system. See COMPLETE SYSTEM DEACTIVATION  under DISABLING & ACTIVATING AIR BAG SYSTEM. Disconnect air bag diagnostic monitor. Remove plastic locking wedge from Gray diagnostic monitor connector. With DVOM set on highest ohms scale, measure resistance between diagnostic monitor connector terminal No. 3 and terminals No. 2, 6, 17, and 18. If all measurements reveal open circuits, replace diagnostic monitor. If any measurement reveals continuity to ground, go to step 3).
  3. Isolate Faulty Impact Sensor  - See WIRING DIAGRAMS  to determine which front impact sensor had low resistance to ground in step 2). Disconnect impact sensor. Measure resistance across sensor contacts. If resistance is not infinite, replace sensor. If resistance is infinite, locate and repair short to ground in low resistance circuit.