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Trying to track down an elusive wiring issue in my 1939 Six. When I depress the floor board dimmer switch, lights go out and car draw serious current as it pegs the ammeter and the thermal bi-metal strip on the headlight switch gets extremely hot.

Does anybody know the pinout / wiring of that 5 pole dimmer switch? Short of that, I'll pull wires one-by-one and track down this short. Schematic shows 5 wires but not what kind of switch this is

Also, the third position of the headlight switch doesn't do anything except draw a short as well. This interacts with the headlight dimmer switch
I did find a short in the left headlight socket, of which I will be ordering a pair Monday Issue with 3rd position persists with socket cut out of the car
There are 3 positions to the headlight switch:
1)Parking lights
2)city or country driving and
3) Country driving or passing lights
The dimmer switch, with headlight swicth in 2nd position, raises both beams to Country (of which only the right light does this)
With headlight switch in 3rd position, successive switching the dimmer switch is supposed to raise or lower the left headlight, of which it doesn't.
Add confusion, left light was not as bright as the right so I temporarily ran a "body feed" wire from the chassis to the headlight bezel. Got brighter but cooked the spring on the bulb contact.

Did you mean 5 pole dimmer switch or 5 wire? Schematics and parts manual show a normal 3 terminal dimmer switch but there are 5 wires connected. I suspect the switch can be replaced with a regular universal 3 terminal two position dimmer switch available from Napa and others if it is shorted.

There were two headlight switch assys in 39 -- an early and late version. Wiring is almost the same between the two but there is a wire to the right front lamp with a relocated position on the later switch. If someone wired using the other version as a guide or the wrong diagram that might be part of the problem.

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Thanks
I am referring to the switch mounted on the floorboard to the left of the clutch. It has 5 wires and based on its function, needs all 5 wires. My dash headlight switch is the top one, later models.

This should help, from the Packard Club site. The switch is at the top-center.

packardclub.org/wiring/1939wiring-6cyl.JPG

Interesting, simple SPDT switch with 5 wires going to it, not a switch with 5 Poles ! Let me digest this !!

Thanks
John

Just had mine out as, when we removed the front end clip, we had to disconnect the headlights and signals; then when we went to put things back together, found issues like you are referring to.
We found the only way we could get things to work properly was to use the second position of the switch (first is parking lights only) and the third made the driver headlamp go bright and dim but not the passenger side. According to your description, maybe that is how they're SUPPOSED to work???

The dimmer switch can be easily removed be taking out the 2 slotted screws in the floorboards and pushing the switch outward. Then if you go under the hood you can reach down and grab it and all the wires are accessible. Mine is 3 contacts, 5 wires, with one contact having 3 wires. I believe the 3-wire contact is the switch leg with 2 wires going to the respective headlight pots. My switch was okay, but I have replaced lots of those floor switches over the years, as they get moisture in them from snowy boots, etc., and corrode. Holes in floorboards don't do them any good either! LOL Been there...
Grounds were also an issue with my wiring, so be sure and clean all your ground contacts. Good luck.

Thanks for the suggestions, will dig into it this week. I know the circuit "works as advertised" because years ago, my Dad and I tried troubleshooting his car for what you are seeing only to read in the manual that is what it is suppose to do.

On yours, if you lok at the schematic provided by Owen in this thread, seems yours is miswired as two terminals have 2 wires, 1 has 1 wire. None have 3 wires attached as you indicated.

John

Hi John,
It's one of those deals where I THOUGHT mine had one contact with 3 wires and 2 with just 1 wire, but now that you say that, I am rethinking my recollections of the switch and think you are probably right!! I think I'm getting old?!?!? That would make sense too, in as much as each headlight has 2 wires for the high and low beam and the other contact would go to the dash light switch. Sorry to 'confuss' the issue....

No Problem !

In reality, only one of the filaments in the Right headlamp goes to the dimmer switch. That pole of the switch is also tied to the Headlight Switch

The "center" pole of the dimmer switch goes to the headlight switch and the remaing pole of the dimmer switch has 2 wires, the other filament of the Right headlamp and off to the headlight switch

Thanks, I stand corrected and better informed!!! Apprec. Chris