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Home >> Ford >> 1993 >> Probe Base, Standard >> Repair and Diagnosis >> External Pages >> Different car >> Section 11 (Air Bag Restraint System) >> Diagnostic Tests >> Code 45, Front Impact Sensor Not Mounted To Vehicle Properly >> Possible Causes
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Possible Causes

WARNING: This page is about a different car, the 1993 Mercury Sable, 1993 Lincoln Continental, and 1993 Ford Taurus. However, it is still accessible from the selected car via links, so may be relevant.

Code 45 will set if there is a poor connection due to loose mounting, dirt or corrosion at left front impact sensor (center front sensor on Sable and Taurus) mounting surface. Code 45 will also set if there is an open or damaged wire between terminal No. 21 of diagnostic monitor connector and front impact sensor. An open or loose wire inside of left front impact sensor (center front sensor on Sable and Taurus) will also cause Code 45 to set.

  1. Verify Condition  - Turn ignition on. Check for fault codes. If Code 45 is flashing, go to step 2). If Code 45 is not flashing, check connectors, wiring, splices and crimps for an intermittent problem. DO NOT  proceed with diagnostic test until code is flashing. Failure to do so will result in needless replacement of diagnostic monitor.
  2. Deactivate System  - Deactivate air bag system. See COMPLETE SYSTEM DEACTIVATION  under DISABLING & ACTIVATING AIR BAG SYSTEM. Leave positive battery cable disconnected. Disconnect diagnostic monitor. On Continental, diagnostic monitor is behind knee bolster, left of steering column. On Sable and Taurus, diagnostic monitor is behind glove box. Set ohmmeter to AUTO or 200-ohm scale. Measure resistance between diagnostic monitor connector terminals No. 21 (Purple/Light Blue wire) and No. 3 (Black wire). If resistance is more than 2 ohms, go to step 3). If resistance is less than 2 ohms, replace diagnostic monitor.
  3. Check Front Impact Sensor Ground  - Disconnect left front impact sensor (center front sensor on Sable and Taurus). Measure resistance between Purple/Light Blue wire in sensor connector and ground. If resistance is less than 2 ohms, inspect circuit between terminal No. 21 and sensor. Also, check all terminal crimps and splices. Repair as necessary. If resistance is more than 2 ohms, remove sensor. Clean sensor mounting surfaces. Reinstall sensor. Go to step 4).
  4. Measure Resistance Of Sensor Ground  - Measure resistance between Purple/Light Blue wire in impact sensor connector and ground. If resistance is less than 2 ohms, circuit is okay. Cleaning sensor mounting surfaces in step 3) corrected problem. If resistance is more than 2 ohms, replace left front impact sensor (center front sensor on Sable and Taurus).
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