Test E: AUTOLAMPS Inoperative
WARNING: This page is about a different car, the 1997 Lincoln Continental. However, it is still accessible from the selected car via links, so may be relevant.
- Test Autolamp Function - Set autolamp switch to AUTOLAMP position. Cover light sensor amplifier (located on top of dash) to simulate darkness. Turn ignition switch to RUN position. If headlights and autolamp indicator turn on, system is functioning normally at this time. If headlights and autolamp indicator do not turn on, check fuse No. 5 (10-amp). Fuse should have power when ignition switch is in RUN or START position. If fuse is okay, go to next step.
- Test Autolamp Sensor - Using scan tool, request PID/DATA MONITOR AND RECORD. Request PID status for LIGHTSN. If PID status indicates light sensor amplifier is ON, go to next step. If PID status indicates light sensor amplifier is OFF, go to step 6).
- Test Autolamp Switch Delay Increase Operation - Turn ignition switch to RUN position. Momentarily tap autolamp time delay increase switch. If message center displays delay time, go to next step. If message center does not display delay time, replace LCM and retest system.
- Check Autolamp Switch Time Increase - Tap autolamp increase switch. If message center display shows an autolamp delay time of 10 seconds to 3 minutes, go to next step. If message center display does not show an autolamp delay time of 10 seconds to 3 minutes, tap switch until autolamp delay time displayed is the desired time. Retest system. Note that autolamp delay time is a memory function and will change with memory recall.
- Test Ignition Switch - Using scan tool, request PID status for ignition switch IGN_LCM. If PID status indicates RUN, replace LCM and retest system. If PID status does not indicate RUN, repair run/start signal circuit No. 640 (Red/Yellow wire) to LCM. Retest system.
- Test Autolamp Sensor Input - Disconnect light sensor amplifier. Turn ignition switch to RUN position. Measure voltage between ground and terminal No. 1 (Red/Yellow wire) at light sensor amplifier wiring harness connector. See Fig 1 . connector pin No. 1 (circuit No. 640, Red/Yellow wire). If battery voltage is present, go to next step. If battery voltage is not present, repair circuit No. 640 (Red/Yellow wire) from fuse to light sensor amplifier.
- Check Resistance From LCM To Light Sensor Amplifier - Disconnect LCM C208 connector. See Figure . Measure resistance of White/Purple wire between terminal No. 10 at LCM C208 wiring harness connector and light sensor amplifier connector. If resistance is 5 ohms or less, replace light sensor amplifier and retest system. If resistance is more than 5 ohms, repair open circuit No. 218 (White/Purple wire) and retest system.