Adding Turn Signals/Electric Wiper

fiftychev

Junior Member
I'm adding some turn signals and an electric wiper to a Model A. When I run the "power wire" from the ignition switch to the wiper or signals they barely work. If I run the "power wire" directly from the battery they work fine. I jumped the ignition switch with no success. The wire to the ignition is coming from the plus side of the coil and is part of the replacement harness. The wires running to the signals and wiper are 14 G. I'd like the signals and wiper to be disabled when the ignition is off so I would rather not run them off an auxiliary wire direct for the battery. Suggestions please??
 
Question, Why do you want them disabled when ignition is off? Your lights are not, the horn is not, Brake light is not. I wired my wiper and signals up to the battery and put and inline fuse on both circuits with no issues. If I want to test my lamps while the car is off, it just a matter of turning them on. Use the K.I.S.S. method and save youself some trouble down the road. JMO.
 
The original wiring of the Model A ignition system places the ignition coil before the ignition switch. I.E. when you connected your wiper, ect., to the ignition switch input, it places the wiper motor in SERIES with the ignition coil. That reduces the voltage to the wiper motor causing it to run slow. If you wish to do what you are trying to do, you must re-wire the coil to be AFTER the ignition switch. Then, the wiper motor (or other accessory) is in PARALLEL to the ignition coil and should as desired.
If a Pop-Out-Switch is installed this modification will not work.
 
You have something there. I think I'm going to follow your lead. What size fuses did you put in the circuits? Thanks for your help!
 
MAG has it right, can't do ot that way.

Get a fuse block and run a wire from the battery to the block, branch out the power to the wiper and the signals.

Now you can get complicated and install a new ignition switch with an Aux position and run a relay off that to the fuse block as I feel that the signals and wiper running at the same time might be a little much for the reproduction switches made today.
 
The original wiring of the Model A ignition system places the ignition coil before the ignition switch. I.E. when you connected your wiper, ect., to the ignition switch input, it places the wiper motor in SERIES with the ignition coil. That reduces the voltage to the wiper motor causing it to run slow. If you wish to do what you are trying to do, you must re-wire the coil to be AFTER the ignition switch. Then, the wiper motor (or other accessory) is in PARALLEL to the ignition coil and should as desired.
If a Pop-Out-Switch is installed this modification will not work.
Mag,
NOT to confuse the issue, but many Model As' have been rewired to a "HOT SWITCH", that works like the common switch arrangement. The switch then supplies current TO THE COIL.
It's easy to do & can easily be changed back to original configuration. It's handy when you need a "KEYED" current source for various accessories.
The "HOT SWITCH" changeover can NOT be done, if you're using a POP-OUT switch.
Bill W.
 
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I remember my Logo-Lites came with a 5 amp fuse ...... not that I have a good memory ..... but when I tried to find a 5 amp spare fuse for my Logo-Lites at Auto-Zone the young lady gave me a frustrated, mean look and told me there was no such thing as a 5 amp fuse.

Then when I asked if she had cotter-keys ..... she told me they did not make keys and instructed me to go to Wal-Mart.

Next ..... asked her if she had cotter pins ....... Wal-Mart was suggested again ..... next to the safety pins in the Hobby Section.

Then I remembered I wanted to get a "feeler" gauge ........ but ...... the store was full of customers ........ so I was not about to ask this lady for a "feeler" gauge.

I left Auto-Zone empty handed ..... funny how we can associate remembering details with different experiences ....... after a few months, I noticed she was not working at Auto-Zone ..... I never inquired why ...... later .... I saw her working at Wal-Mart.
 
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Could you relay switch the power? Use the pop out key to act as an activator circuit for the relay, similar to having to have your head lights on dim before the fog lights come on? Then you'd have circuit protection via the relay, and it would be switched with the key. It's been a while since I wired a relay so don't shoot me if I'm wrong on this


Looking for the front bumper emblem that has "Ford, Made In Canada"
 
Could you relay switch the power? Use the pop out key to act as an activator circuit for the relay, similar to having to have your head lights on dim before the fog lights come on? Then you'd have circuit protection via the relay, and it would be switched with the key. It's been a while since I wired a relay so don't shoot me if I'm wrong on this

Putting a relay on the ignition side of a pop-out switch won't work.
 
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