I was checking out this website, which is about the restoration of a GM Futureliner the other day: http://www.futurliner.com/ Eventually, I got to the Autronic Eye section: http://www.futurliner.com/autronic.htm I'd run across this before, as they were actually working on this restoration (which completed in 2006), and pocket this information, as well as John Oldenburg's name for later use. Hell, I've even included his info in my "Finding Cadillac Parts" thread: http://www.jalopyjournal.com/forum/showthread.php?t=298882 John Oldenburg Rebuilder of Autronic Eye systems http://home.comcast.net/~oldsfan/MySite/oldenburg.html 263 North Rocky Hill Rd Galena, IL 61036 815-777-2937 Anyway, John has some really good information he shared on the Futureliner site. I figured I'd pass it on, just as I found it here: http://www.futurliner.com/autronic.htm The picture above consists of all of the components associated with the AUTRONIC EYE that will be re-installed on the Futurliner. John Oldenburg has donated his services, components and instructions for installation. John Oldenburg has been restoring Autronic Eyes for over 20 years. He sent us some information prior to shipping the package: "I ran a final test with one tester that I use to test all the units of those years, I have 21 of the testers, but I use only one for the final test to make sure all units leave with the same calibration settings. After I installed the wiring harness, it changed the setting and was slow to dim. I discovered that with the long wiring, there was a voltage leak that was coming back to the amp as a signal that it was dark and locking the high beams on. I removed the wiring and used shielding on the wire all the way to the ends. Normally, in a car, the wiring is only 3-4 foot long and would not matter, but this harness for the Futurliner is 26+ foot long. I have sent additional terminals if you need them. In the center of the coil of wire is the actual unit that will be installed on the dash. The Autronic Eye was an automatic headlight dimming system that dimmed the Futurliner headlights when traffic approached. From what we've picked up from the Paraders that drove the Futurliners, the units weren't very practical and seemed to dim the lights for everything except oncoming cars. Every streetlight activated it, and so you go down the street with your lights flashing up and down. Out in the country, reflection from highway signs set it off and oncoming cars often don't activate it soon enough and they flash their high beams at you before it dims for them. If you happen to be on a curve at the time, the sensor is looking out in space and never does see the oncoming cars." COMMENTS ON THE AUTRONIC EYE FROM John Oldenburg I remember the first time I saw a phototube, or as many people call the "eye" It was perched on the dash of a 1962 Oldsmobile StarFire, it looked like something from outer space, I let my curiosity get the best of me, I knew I wouldn't be satisfied until I knew everything about this option. Over the years I have restored and repaired hundreds of Autronic eye and Guide-matic systems for all divisions of General Motors, and Ford Lincoln. The first of automatic headlight dimming systems were called Autronic eyes. They were first offered in 1952 for Oldsmobile and Cadillac. All other divisions started 1953. They kept his name until 1959. 1960, and up the name was changed Guide-matic but it served the same purpose, to automatically switch the head lamps between upper and lower beams in response to light from an approaching car. Lincoln started purchasing Autronic eye's in 1957, Ford and Mercury and 1964, before this they had a high failure rate until they started purchasing units from Delco. The typical system consistent of four individual units, the photo, amplifier, power relay, and a special foot dimmer switch, or a auxiliary override footswitch. In 1955 Oldsmobile offered the first on/off switch integrated into the headlight light switch, this was the only division to offer this until 1962 when Cadillac and Buick had a off switch built into the phototube. Many people asked me how to identify a Guide-matic system or an Autronic eye for there car, I think we have all been to swap meets and seen parts or complete units that a vender is trying to sell. But was not sure what it was off of, if you ask the vender, he may ask what car you have first, before he tells you the car you have, or we have all heard "they are all the same in those years" this is not true! Some of the first clues are the shape of the phototube lens. The square clear lens was used in 1952-54 (mid year) but Chevy retained the square lens until mid 1955. But this was only to use up old inventory. Chevy only, used 6-volt Autronic eye systems on 12-volt cars with a special 12 to 6volt reducing resister. This was a poor idea, as it was a larger load on the charging system. But it was cheap! The round clear lens was first used in 1954 and lasted through 1958 on Cadillac and Oldsmobile. Buick, Chevy Pontiac retained the round lens through 1959. The 1959 Cadillac and Oldsmobile unit was a one-year only unit, and a breakthrough in technology as this was the first of the low voltage units. The phototube was supplied with just 2.25 volts. This phototube was still large but the lens was oval and clear and there was a knob on the back to adjust the sensitively while driving. There was one exception a 1959 dealer installed unit that was a high voltage DC unit. The amplifier was mounted behind the kick panel (all amp's were here in 1959 through 1962 in Cadillac, all others 1958 through 1962) this phototube had a knob on the back of the eye as well and a clear round lens. There was a large (black box) or the amplifier under the hood of the car,. If it had one adjustment knob under it, it was used for 1954 and earlier, 1955 and earlier for Chevy. This was a high voltage DC unit. If it had two knobs, this was a high voltage AC unit and was used in 1955-58. This means the phototube was supplied with up to 1000 volts to operate the system. 1958 was the last of the large amplifier under the hood for Cadillac and Oldsmobile. In 1955-58 Oldsmobile used a rubber isolation system on the amplifier to reduce shock or harmonic vibration. This had 2 separate metal legs and 4 large rubber isolators. The 1960 phototube was another breakthrough, This was the first year of the small phototube. it had a amber color lens to make the system less sensitive to fog or snow. The earlier ones had this as well but was inside the phototube housing. In the Cadillac division only, the phototube was removed from the dash in 1964 (unless it was a dealer installed unit or a professional car) and installed behind the fender or grill. These units are unserviceable and should be replaced if not working. The first and only year to sport a "safety salute" was 1960, this was a two-step relay. When the headlamps were switched to low beams the upper beams would remain on at a reduced candle power for one to two seconds to indicate the car was equipped with a Guide-matic system. This was a great idea, but poor design and thus had a very high failure rate. There was several attempts to salvage this part of the system by the GM tech dept. but by February of this year GM sent notification to all dealers to disconnect this parts of the Guide-matic system if there were problems. The phototube mounting changed almost every year with the new contours of each dash. You have to make sure you have the correct one for your car. On a Cadillac it is easy to make sure you are mounting the phototube in the correct location, as the holes are there for you, in the steel dash anyway. Just take a awl and poke a hole through from the under side. For other divisions you must have a template, mark and drill a hole from the top. The next clue to check the serial number printed on a paper sticker on the amplifier. If the amplifier was mounted under the hood of the car for a long time the tag maybe deteriorated and fell off. The phototube had a metal tag in the years 1952 through 59 and a paper tag between the phototube and mounting in 1960 through 66. The serial number consists of nine digits. The first digit indicated the division this unit was sent to. The second and third digits indicated what year the unit when into. The remaining 6 digits indicated the serial number starting with number one. If you run across a very high number starting with the 100,000 range, this means there may have been a minor mid year production change. Here is a breakdown of the model and serial numbers as they apply to the various car lines; 156 000001 Chevrolet 256 000001 Pontiac 356 000001 Oldsmobile 456 000001 Buick 556 000001 Cadillac 857 000001 Lincoln. An "A" will follow the serial number 1964 and up 864 000001-B Mercury 864 000001-C Ford 756 000001 Warrant Replacement. The number 7 was GMC truck division and no automatic headlight dimming system were ever used in trucks *There is a exception to this coding, in 1952 this system of numbers was not used yet, but it still had a serial number with all 9 digits. After properly identifying and making sure the Autronic eye is complete, It is time to start restoring the unit, The bad wiring should be replaced with new. Next make sure all connectors are clean and free of corrosion (all electrical connectors on the car should be cleaned, at these were made of brass and on a 40 plus year old car they will tarnish making poor connection). The amplifier housing cover 1952-1958 should be glass blasted, primed then painted gloss black, the phototube and mounting should be dissembled, and glass blasted, primed and painted the color of your dash. If this unit was originally purchased over the counter at the dealer the phototube was painted Cumulus gray or dark gray, 1960 units and later, the housing was sent in primer, either red or dark gray. All vacuum tubes should be replaced or tested to make sure they are in top working condition. The vibrator in the amplifier (1952-1958) should be replaced with a solid-state replacement vibrator, which will last for many, many years. Today driving standards have changed considerable from yesteryear. In 1956 it was dark out there! Today we have halogen headlights, reflective signs, and reflective paint on the highways, so, if we would use the factory sensitivity adjustments, your upper headlamps would seldom turn on. Though many hours of testing of my own cars, I've recalibrated most of my factory testers, most all dealers had one or more of these. Once the unit is running I have always let it run for several hours, if not days, to see if it is going to fail. In my option if the unit is going to fail it will do so in the first 24 hrs of operation. Another option that was available on Cadillac and Buick was the "twilight sentinel" this was first used in 1960. I am often asked if this option was part of the guide-matic system, It is not. It is a completely separate unit from the Guide-matic. This is a electronic device which automatically turn the headlights on and off. The operation of the lights is determined by the amount of daylight available for safe driving. The twilight sentinel used the same numbering system as the Autronic eyes, but the number always started with the letter "L".