I've filed thru the forum and have not found much about anyone repairing their Guidematic system. This is something that is low on my to-do list as the dim/brights work just fine on my 64 Fltwd, but is something I would like to make functional in the future. 

Has anyone endeavored on this? Is it difficult? Impossible? How "gimmicky" is it when functioning properly? Unfortunately, I do not have a time machine to see how these functioned from the factory. 


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The 1964 Guide-Matich headlight control systems ins covered in the 1964 Cadillac shop Manual on pages 12-85 to 12-92. My 64 Coupe de Villes came with this feature, was disconnected at some point and is one option I will probably never try to get back working or would install on another car. I am told, and believe with the many lights we have on the road and everywhere now in city and suburban driving, the headlights would be constantly going back and forth from low beam to hi beam to low beam. If in a rural area I could see this as a much more useful feature. Perhaps others that have this feature working can chime in and let us know there experience.

Personally, after owning a 64 with a working Sentinel headlight control on another driver car for a few years way back, that would be the headlight control system I would like to add to my 64. On at dusk, off at dawn, and a delayed shut-off as you exit the car. That is also a feature that I remembers impressing people the most as I would exit my car at night (or more often my early morning commutes to the parking deck at work), when people would remind me that I had left the headlights on and would say, give it a few seconds.  You can adjust the delay time, and found this to be a nice feature exiting in dark area.
Just my 2 cents. Check out the Shop Manual for details on both systems.

I wondered about how it would react with as much light on the roads we have today as you mentioned. 

I have driven a modern Cadillac with the auto headlamps and quite enjoyed their functionality. I’m guessing they have greatly improved that tech as streetlight and other ambient light sources seemed to have no affect on whether they were on or off. This is a big contributor to if I would invest time and resources into repairing the system as I do live in a fairly rural area, but do encounter my fair share of street lights. 

Thanks again for the excellent report!




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