I have a 1978 Lincoln Town Car I recently purchased that has a 2 part problem with the Automatic Headlight Dimmer/Delay system. The first is the autolamp feature, when turned on, regardless of the position of the switch for the delay, the headlights never turn on, but the parking lights and instrument panel do, but turn off instantly, no delay, when the ignition switch is turned off. The second is with the automatic dimmer, when it detects oncoming light it will put the lights in low beam but does not return the high beams back most of the time. What do you think?
Greetings Dave –
Congratulations on your recent Lincoln purchase. The popular Autolamp and Automatic Dimmer options are a real nice luxury option to have but of course can be a real pain when they fail. The diagnostic procedures are very well presented in the Factory Shop Manual and would be a great item for you to have now and in the future. Without being there on site to actually diagnose the system for you I can only at this time offer you some of the problems that we have encountered with them here at Lincoln Land.
If the parking lamps and instrument lamps are turned on Automatically as you describe but the Headlamps are not, this is usually caused by a bad connection or contact located inside the Amplifier module. Of course any wiring involved in that circuit can also be suspect. This is the reason that a proper wiring diagram as shown in the manual is a real plus in order for you to troubleshoot and pinpoint your problem.
The Automatic Headlamp Dimmer system is notorious for developing failed Amplifier Sensor units that are located behind the left headlamp assembly. This unit is completely sealed and not repairable. Again the tests for this option are well shown in the manual.
I do hope that the above helps and if you do require any manuals, parts or further information. please do not hesitate to contact us at any time.