1950s 59 no headlights/taillights

[Cadillac Jack 82]

Okay so I have turn signals and brake lights...but when I pull the switch out I have no headlights, taillights, or dash lights.  Bad headlight switch?  Fuses look fine.

[Dave Shepherd]

Not so fast, check for power into the switch first.

[Cadillac Jack 82]

I now have dash lights but nothing on the front or back.

[V63]

Headlight switch is protected with a thermal bi metal breaker, could be corroded contacts. Check your head light ground leads. Dipper switch can be problematic too.

[Cadillac Jack 82]

Grounds are clean and connected.  Guessing the relay is the issue.  Btw where tf is the autronic eye box on the 59?  Also wanna check that.

[Eric DeVirgilis CLC# 8621]

Keep in mind the Autronic Eye controller uses vacuum tubes and needs a while to warm up before the system will work, especially when it hadn't been used for some time. On a '59 I had, it took nearly half an hour. 

[Gabe Davis]

Btw where tf is the autronic eye box on the 59?  Also wanna check that.

It's behind the kick panel in the drivers side. The piece with the vent grille comes out and it's wedged in there. The door sill has two silver plugs pressed in. That's how you can adjust the pots of the unit. The three screws holding it in are also in the door sill.

[Cadillac Jack 82]

Makes sense why the kick panel is out of place.  I'll take a look at it tomorrow.  Thank you.

[Cadillac Jack 82]

Update-  I managed to get everything working but the headlights.  Turns out a connector was unplugged and after I reconnected it I now have taillights, parking lights, courtesy light, and fog lights.  The connector appears to be missing a wire however which I assume connects to the autronic eye.  Would this cause the headlights not to work?

[Gabe Davis]

The connector appears to be missing a wire however which I assume connects to the autronic eye.  Would this cause the headlights not to work?

If I remember correctly, the Autronic Eye can be completely unplugged from the system and the lights will behave as you would expect. There are two connections that go to the control box for the Autronic Eye. One is from the photo tube light sensor and the other goes to the foot switch for high-low.

The 1959 version of the eye was one year only and was different from previous years. It uses a low voltage for the photo tube. The schematics that are in the 1959 shop manual are not correct and show a high voltage version.

Be sure to take a look at the foot switch too. I took mine out and flushed it with a lot of contact cleaner and deoxit spray. I didn't open it up but was able to get the spray in the gap around the plunger. The switch actually has a momentary position when pressed lightly to override the eye and then the other two positions when pressed harder on and off. It controls the power relay that actually switches the headlights.

The power relay is under the hood on the wheel well by the washer jar. I'd check there too and make sure there is power when the headlight switch is on.

The light switch - make sure you have power on the head light connection when switched to on.



The wiring diagram shows a jumper on cars without fog lights. Does your car actually have them? Could this be the missing wire you describe?

[Cadillac Jack 82]

Thank you.  I'd like to try some night cruising soon as the weather is finally getting nicer here in AZ.

[Gabe Davis]

Here is the Autronic Eye wiring diagram from the shop manual. Again, the circuitry shown inside of the control box is incorrect but the rest of the diagram is right.

Looking at the power relay, I'd check to see if you have power on the Light Blue wire coming from the headlight switch going in to the relay when the switch is on. If you have no power there then it is the switch or wire between the switch and power relay.

[Cadillac Jack 82]

Perfect hopefully I can get them working on Saturday.

[Cadillac Jack 82]

Okay I'm going nuts.  Everything's connected and nothing looks burnt or broken.  All the lights work except the headlights.  Any ideas?  I'm going nuts trying to figure this out.

[Gabe Davis]

Did you put a multimeter set to DC volts between a good ground and the 16ga light blue wire on the three pin connector at the power relay? That will tell you if your headlight switch is sending power to the relay which then goes to the lamps.

That's where I'd start given the info you have shared so far. Depending on the results you know whether to work backward to the headlight switch or forward toward the lamps.