Key-In Ignition Switch
DIAGNOSIS AND TESTING Key-In Ignition SwitchWARNING: ON VEHICLES EQUIPPED WITH AIRBAGS, REFER TO RESTRAINT SYSTEMS BEFORE ATTEMPTING ANY STEERING WHEEL, STEERING COLUMN, OR INSTRUMENT PANEL COMPONENT DIAGNOSIS OR SERVICE. FAILURE TO TAKE THE PROPER PRECAUTIONS COULD RESULT IN ACCIDENTAL AIRBAG DEPLOYMENT AND POSSIBLE PERSONAL INJURY.
1. Disconnect and isolate the battery negative cable. Disconnect the instrument panel wire harness connector from the key-in ignition switch connector receptacle on the ignition switch. Check for continuity between the key-in ignition switch sense and ground terminals of the key-in ignition switch connector receptacle. There should be continuity with the key inserted in the ignition lock cylinder, and no continuity with the key removed from the ignition lock cylinder. If OK, go to Step 2. If not OK, replace the faulty ignition switch unit.
2. Check for continuity between the ground circuit cavity of the instrument panel wire harness connector for the key-in ignition switch and a good ground. There should be continuity. If OK, go to Step 3. If not OK, repair the open ground circuit to ground as required.
3. Disconnect the gray 26-way instrument panel wire harness connector from the Body Control Module (BCM) connector receptacle. Check for continuity between the key-in ignition switch sense circuit cavity of the instrument panel wire harness connector for the key-in ignition switch and a good ground. There should be no continuity. If OK, go to Step 4. If not OK, repair the shorted key-in ignition switch sense circuit as required.
4. Check for continuity between the key-in ignition switch sense circuit cavities of the instrument panel wire harness connector for the key-in ignition switch and the gray 26-way instrument panel wire harness connector for the BCM. There should be continuity. If OK, use a DRB scan tool and the proper Diagnostic Procedures to test the BCM. If not OK, repair the open key-in ignition switch sense circuit as required.