Possible Causes

Code 45 will set if there is a poor connection due to loose mounting, dirt or corrosion at center impact sensor 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 impact sensor 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. Diagnostic monitor is located on left side of steering column under instrument panel. Set ohmmeter to AUTO or 200-ohm scale. Measure resistance between terminals No. 21 (Brown/White wire) and No. 3 (Black/Green wire) of diagnostic monitor connector. If resistance is more than 2 ohms, go to step 3). If resistance is less than 2 ohms, replace diagnostic monitor.
3. CHECK CENTER IMPACT SENSOR GROUND  - Disconnect center impact sensor. Measure resistance between ground and Brown/White wire of center impact sensor connector. If resistance is less than 2 ohms, locate and repair open in Brown/White wire between terminal No. 21 and sensor. 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 ground and Brown/White wire of center impact sensor connector. 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 center impact sensor.