'51 Light Switch Questions

[Chuckwp]

I am wiring a 51 coupe for a customer using a modern 12 volt harness.  I want to know how the light switch functioned origionally. Im not familar with this type of rotary light switch  as opposed to a GM style pull on type switch.
The switch has two positions. The first position has continuity from input to output on 4 out of the five terminas on the back and moving to the the second position sends power to the 5th terminal. 
What do these positions corrospond to? Is the first postiion front and rear running lights and the second adds dash and headlights?
I also assume that the light switch sends power to the dash light dimmer switch since it does not have on actual off position and sending power from anywhere else would resulg in

the dash light always being on.
My thinking is if I connect 2 terminals to the front park lights and 2 to the tail lights the first position will light front and rear lights.  Use the single terminal to send power to the dash lights and headlight dimmer will result in front and rear running lights working in the first position, and all lights working in the second position. So,  there is not really a seperate function to send power to just the front running lights? 
 

[Sniper]

Trying to wire a car without the manual?

 

 

[desoto1939]

As I have stated many times over and over and also have other antique car owners on this forum. There are several basic catalogs or manuals that you need and should have for your car if you plan to work on the car and or even if you take it to a mechanic.

 

1. Service Manual

2. Parts Manual

3. Chiltons or Motors generic service book

4. Hollander Interchange manual that tells you which parts will fit from other years

5. ANy other specific catalogs that might provide part references that were made by other part manufacturers.

 

Hartung

[Sniper]

I believe the OP is the mechanic not the owner

[Chuckwp]

59 minutes ago, Sniper said:

Trying to wire a car without the manual? 

  American Auto Wire harness, 12 volt negative ground, set up GM style lighting system . This helps showing what they did. I was pretty much there but, this clears it up.   -Thanks. 

 

 

 

Edited December 15, 2022 by Chuckwp

[LeRoy]

4 hours ago, desoto1939 said:

As I have stated many times over and over and also have other antique car owners on this forum. There are several basic catalogs or manuals that you need and should have for your car if you plan to work on the car and or even if you take it to a mechanic.

 

1. Service Manual

2. Parts Manual

3. Chiltons or Motors generic service book

4. Hollander Interchange manual that tells you which parts will fit from other years

5. ANy other specific catalogs that might provide part references that were made by other part manufacturers.

 

Hartung

who needs a manual when we have you guys

[desoto1939]

9 minutes ago, LeRoy said:

who needs a manual when we have you guys

The manual in this case would have shown where each wire is connected and to what switch.  Lets say you are on a trip and you break down on the road and you can not get access to the internet, so in this case you are left on your own.  But if you have the basic manual at least you can trace the wires. Also it is a great learning and teaching manual about your car.  You also have to remember that the mechanics of today have not been introduced to 6 volt system positive ground and also very few even know about tuneups for cars that have points, condensers. So the more that you know about your car the more assured you are about fixing it when stuck on the road.

 

Todays antique car owners have changed along with the hobby. Most of the older owners gained knowledge by working on their cars, and basically these older cars were quite simple as compared to our modern cars. Most owners would do tune-ups change the oil and the basic maintenance items on the car. But in todays world with the modern cars most owners do not have any idea of which wire is a sparkplug wire, how to change the oil and oil filter and even the basic tire change if you get a flat tire. We now rely on someone else to do that job for us and expect people to just provide any answer to our questions no matter how basic or complex.

 

So by getting the manual and reading it section by section you will get to know your car. Some of these cars had a specific set of procedures that you needed to do prior to starting the car and this was not just turning on the ignition key. So lets say you are driving at night time and your headlight all go off.  What would you do. If you had read the service manual and or owners manual you might have discovered that there is a fuse in the headlight switch and you could check the fuse and replace it. But if you have no knowledge of this then you are stuck on a dark and lonely deserted road and hopefully you have a fully charged cellphone and then call for a towing service with a possible 1-2 hour wait time to get towed back home ot to a local garage.

 

So the possibilities are endless, I am not trying to put anyone down, but take some ownership and read the service manual and get to know your antique car.  Knowlege is a great power to have and hold and when you take the car to a garage at lest you can tell the mechanic what you tried to do to diagnosis the issue.

 

I have had my 39 Desoto for 35 years and I am constantly learning more about my car and I am not a skilled mechanic.

 

Rich Hartung

 

[LeRoy]

4 minutes ago, desoto1939 said:

The manual in this case would have shown where each wire is connected and to what switch.  Lets say you are on a trip and you break down on the road and you can not get access to the internet, so in this case you are left on your own.  But if you have the basic manual at least you can trace the wires. Also it is a great learning and teaching manual about your car.  You also have to remember that the mechanics of today have not been introduced to 6 volt system positive ground and also very few even know about tuneups for cars that have points, condensers. So the more that you know about your car the more assured you are about fixing it when stuck on the road.

 

Todays antique car owners have changed along with the hobby. Most of the older owners gained knowledge by working on their cars, and basically these older cars were quite simple as compared to our modern cars. Most owners would do tune-ups change the oil and the basic maintenance items on the car. But in todays world with the modern cars most owners do not have any idea of which wire is a sparkplug wire, how to change the oil and oil filter and even the basic tire change if you get a flat tire. We now rely on someone else to do that job for us and expect people to just provide any answer to our questions no matter how basic or complex.

 

So by getting the manual and reading it section by section you will get to know your car. Some of these cars had a specific set of procedures that you needed to do prior to starting the car and this was not just turning on the ignition key. So lets say you are driving at night time and your headlight all go off.  What would you do. If you had read the service manual and or owners manual you might have discovered that there is a fuse in the headlight switch and you could check the fuse and replace it. But if you have no knowledge of this then you are stuck on a dark and lonely deserted road and hopefully you have a fully charged cellphone and then call for a towing service with a possible 1-2 hour wait time to get towed back home ot to a local garage.

 

So the possibilities are endless, I am not trying to put anyone down, but take some ownership and read the service manual and get to know your antique car.  Knowlege is a great power to have and hold and when you take the car to a garage at lest you can tell the mechanic what you tried to do to diagnosis the issue.

 

I have had my 39 Desoto for 35 years and I am constantly learning more about my car and I am not a skilled mechanic.

 

Rich Hartung

 

I was blessed with an old man that was a Chrysler tech in 1950 (he is 84 years young), he and I have taken my old car apart and put it back together down to the last screw (which we lost). We did have a motors manual that was about 5 years too young for the car but its still pretty close, we also have the actual Mopar manual for this car on CD. Speaking of road trips I'm getting ready to set off on my first far from home trip in this car and having the laptop w/manual loaded is one of the things in my emergency kit, along with many spares and most of my tools. I've considered lowering the rear a touch, 300 lbs of tools in the trunk will do the trick .

[LeRoy]

1 minute ago, LeRoy said:

I was blessed with an old man that was a Chrysler tech in 1950 (he is 84 years young), he and I have taken my old car apart and put it back together down to the last screw (which we lost). We did have a motors manual that was about 5 years too young for the car but its still pretty close, we also have the actual Mopar manual for this car on CD. Speaking of road trips I'm getting ready to set off on my first far from home trip in this car and having the laptop w/manual loaded is one of the things in my emergency kit, along with many spares and most of my tools. I've considered lowering the rear a touch, 300 lbs of tools in the trunk will do the trick .

I'd still take you guys and your school of hard knocks training over the manual

[Sniper]

It is incumbent on us to pass along our knowledge.  Whenever I can I involve my 17 yo son in car work.