Ron K.

'40 Cabriolet Electrical Problem

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I am dealing with the original system with some rewire in the past and for some reason I don't have power to my ignition switch (or headlights), it had worked fine until recently.  I have 6v to the two outside poles on the device/block on the inside of the firewall but none to the center pole to which the ignition switch is wired.  I think that the Wiring Diagram is calling this device a Circuit Breaker, is there a way to reset it?  Any help, advice or instruction that you can give me would really be appreciated.

 

Ron

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The circuit breaker is strictly for the headlights...Big yellow heavy wire is hot, coil resistors are fed from

switch-look at connections  on starter solonoid under hood, chk coil resistors before and after--chk bunch of

wires on circut breaker device.. 

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Thank you Mssr. Bwatoe for your help.  I do have power to the solenoid because the starter works fine.  It appears to me that on my car both the wire to the ignition switch and the wire going to the headlight switch are wired onto the same pole on the "circuit breaker" so neither have 6 volts.  As mentioned before, I do have 6 volts to the "box' because the two outside poles are hot with 6 volts (the middle pole to which the headlights and ignition has no power).  What is the purpose of that box and how do you reset the circuit breaker.  What if I wire the ignition to one of the hot poles?

 

Ron 

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The power comes from the hot side of the solonoid, then feeds the breaker panel--chk solonoid..power right 

off battery,same post as batt cable..big harness

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Yes sir and that is why I do have power to the "CB" boxout how do I remedy the lack of power to the headlight/ignition post?  Can the breaker be reset or does it have to be replaced?

 

Ron

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the breaker only operates the headlites---power off solonoid feeds panel  big yellow wire--that needs to be hot-that feeds key, which 

feeds coil resistors...all else is non keyed, all hot,, blower, radio lighters all feed from here

IMG_2151.JPG

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post on right top is hot--with various feeds, fuse holder for radio--big yellow hot in, to regulator to ign

top left after "buzzer"circut breaker to protect from heavy draw from lights.

40 circut breaker.jpg

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Ron,

       I'am having trouble attaching a scanned wiring schematic  (47-48 LC/LZ) wiring schematic to this post, so send to me your 

"E" mail address.   I'am Larry Butcher,   "E"     zephyr38@verizon .net

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47-48 HAS LOTS MORE  COMPLEX, AND DIFFERENT BREAKER--BLINKERS, OD, WINDOWS,MULTIPLE HEATERS--

ADD LOTS OF CONNECTIONS NOT PRESENT ON PREWAR 40   HERE IS FORD, SIMILAR--

Flathead_Electrical_wiring1940std.jpg

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Thank you for all of your help, with John Murphy's help I referred to the Service Manual and on page 38 I found my circuit breaker, my car was retrofitted with a 1941 breaker and to muddy the issue even more, the rewiring done by the previous owner is nonstandard so that the color code is of no use.  Sure is fun owning a 78 year old car with some 65 year old wiring and  Lincoln V-8 engine.  I still have the problem but will eventually sort it out.  Thanks again.

 

Ron

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Your ignition switch should be wired to the terminal closest to the ignition resisters, this is the one that should have the wire that comes from the battery side of the starter solenoid. The center terminal is for the headlights and the terminal furthest from the resisters is for the brake lights and other misc electrical.

 

It appears that the contact points for the headlight circuit breaker are not making contact. You can remove the cover and try cleaning the contacts with a fine burnishing blade or if you cannot find a fine blade, you can try some tuner and contact cleaner sprayed on a piece of cardboard and pulled through the contacts. Do not use sandpaper as it will remove what is left of the silver plating on the contacts.

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Ahh...thanks I will do it.  I found a  wiring depiction for a '41 Mercury circuit breaker in my old Ford Service Manual and I believe that is how it shows the wiring to be.  I appreciate the tip.

 

Ron

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