Classic cars forum & vehicle restoration.

[alastairq]

Years ago I bought what was advertised as a 'light switch'...for a 'special' I was building.

I forget where it came from, but I also got some Model A Ford rear light clusters...which I have never used.

For years I have tried to decipher the pin layout on this switch, a rotary device.

Well, today, I decided to have another attempt, using a meter. [It was raining!]

I guessed which pin was the battery pin, and proceeded to write down what connected and disconnected as the switch was rotated.

I also searched the internet, and eventually made one or two discoveries.

The switch was wired to suit USA lighting rules, not UK rules.....I had discovered the differences when trying to UK-ise my Dellows lighting arrangements..it had gone to the USA in the 1990's [where it was raced]....and I had repatriated it.

Thus, what I have is a Cole-Hersee 72051-03 rotary light switch....I discovered. [Sold in the UK as a light switch!!!!]

One US dealer's website had some old wiring diagrams for various switches..including a blueprint [!!} of the one mentioned. It had the battery terminal marked, but he others were blank, so a trawl through tinternet again found another dealer who described what each position effectively did.....so I put the two together.

It seems, in hte USA, they don't like one being able to drive on sidelights alone [exactly what they do when the park at night, I know not]..so there is no 'parking light' position on the switch.

It's either HST and dash, or the same but main beam...or, the same, on main beam, but no dash lights!

It seems, going back and forth from dip to main could be somewhat fraught? The risk of going one click too many, and plunging oneself into total darkness may be quite high!

I decided I would not use the main beam connection....but lnk dip beam to another dip switch for main beam [relays and stuff].
But, the headlights will come on before the sidelights on their own.


The Dellow has its Ford switch wired for either dip or main beam [plus sidelights]....I have left these alone for now....I can cope, I think..the biggest risk of going from Main to Dip is, turning the ignition off!!

But, I have wired in another [toggle] switch to illuminate just the side lights alone.....not quite what Mr Ford had in mind, but........

Aaahh,the wonders of the internet.....how many of us would [literally, perhaps?} be in the 'dark' without it these days?

[47Jag]

Alastair,

My recollections of North American lighting is that the 1st position is side and tail, the 2nd is side off tail and headlights on. So you should wire your sidelamps to the tail terminal along with the dash lights.

If you have a separate dip switch then jumper the dip & main and take that to your dip switch so it won't matter if you overshoot a position.

Art

[Ray White]

This idea must have have been around for quite a while in the States. My '26 Dodge Brothers tourer has the same lighting sequence. You can't have headlamps and side lights on together.

[Peter_L]

I haven't researched this, but could this idea of turning off the side lights been a power saving feature, just as they adopted and still use "grrrrrrrrr" a system that turns off the brake light and flashing it as a turn signal.

Why North America still hangs on to Red rear turn signals is beyond me. They also have never standardised lights for emergency vehicles.

[Ray White]

I am far from expert in electrics but I wondered if the idea was to prevent the switch from getting over loaded?

[alastairq]

http://www.littelfuse.com/~/media/commercial-vehicle/2d-prints/switches/rotary/littelfuse-switches-headlamp-rotary-2d-prints.pdf

The upper diagram is the switch I have.



http://www.littelfuse.com/products/switches/rotary-switches/rotary-headlamp-and-light-switches/72051_03.aspx

The Tech Resources give the key positions & what they do, so it's easy to transfer to the diagram's legend.

A good, tough, switch, of good quality. Note the reference to 'Packard connectors?'

[47Jag]

Alastair,

I would suggest you use #2 for side and tail lights and #4 for the headlamps. That way it won't matter if you overshoot to the fourth position. Again this assumes you will be using a separate dipper switch.

Art

[alastairq]

Yes, I agree...

However, at some point in hte past, I razor-sawed a cut through the brass terminals of #4 connector, separating [electrically] the two #4 positions....in other words [note the 2 rivets for #4?]...using the spade terminals, I isolated #4 in the 3rd switch position...discovering that the switch's wiping contact touched the two # 4 internal terminals separately.

Thus, 1st position = All off.
2nd pos = 1-2-3-5
3rd pos= 1-2-5 [#4 terminal is contacted, but only one...which I severed.]
4th pos= 2-4-5

All rather academic, really, as I didn't use the switch.
Also, a pity some sort of diagram didn't accompany the thing when I bought it?

[ajlelectronics]

[alastairq]