testing dash wiring

1930artdeco

Well-known member
OK, I have a few wires left to add to the dash wires and she will be done. I have two questions:


1) I have 6v battery that I can use to test the circuits/lights-just testing to see if I get current through things. What is the best way to set it up? I am thinking hooking the + side to the ign. switch either batt or start but how do I hook up the neg. side? Just clamp it to the dash somehow?


2) On my ign. switch I have BATT/ACC/IGN/START these fairly obvious. But I am looking at the stock wiring diagram and it has the following on the ign. switch AM/S/AC/C. I am thinking that AC is for accessories but what do the other stand for? I am having to blend my Ron Francis kit with some stock wiring.


Thanks,


Mike
 
When I rewire a car I’m cautious. I use a cheap fuse holder with a 20 amp fuse from the hot lead to the battery. That will handle one at a time, the lights, turn signal, etc. If it blows there’s a problem. When all the problems are gone, you can hook up the battery and hit “start”. The starter itself is the only big load, and it’s really big. If it doesn’t crank, quit. Smoke isn’t good.

In your case just fuse the positive side with jumpers and a fuse and ground the negative. Or the opposite if you’re still positive ground. Really doesn’t make any difference, you’re just trying to protect from a dead short.
 
Thank you for the info about a fuse kit. I will grab one from napa tonight with some other things. The system is 12v, I am just using the 6v to send some current through to see if I get current coming through. The dash is out of the card right now but will in if all is functioning and when the drains get fixed.
 
. . .
1) I have 6v battery that I can use to test the circuits/lights-just testing to see if I get current through things. What is the best way to set it up? I am thinking hooking the + side to the ign. switch either batt or start but how do I hook up the neg. side? Just clamp it to the dash somehow?
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(deleted)
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EDIT... I just missed your post from 9:39 AM
You confused me (easy to do these days) I thought you were working on / asking about a '55.

Not sure I understand your reasoning for using a 6v test battery.
What year is the vehicle? Assuming it's '57 or newer do you have the correct dash gauge voltage regulator?

The test wire from the Negative battery terminal will fasten to the shell / frame of the dashboard with any convenient bolt or screw, and the test wire from the Positive battery terminal will fasten to the "Battery" terminal of the ignition switch. Its terminals are labeled in the plastic.
Yes a fuse in your test leads (with several spares) is a Very good idea.

. . . 2) On my ign. switch I have BATT/ACC/IGN/START these fairly obvious. But I am looking at the stock wiring diagram and it has the following on the ign. switch AM/S/AC/C. I am thinking that AC is for accessories but what do the other stand for? I am having to blend my Ron Francis kit with some stock wiring.
. . .
The individual wires on the Battery and Start terminals on the ignition switch should be self explanatory.
The "Ignition" terminal has a wire going to the Ballast resistor & ignition coil (unless you're using electronic ignition) and a couple wires powering the dash gauge voltage regulator and the Oil & Gen 'idiot' lights.
Any other wires for the ignition switch go on the Accessory terminal, unless you have too many and need an add-on relay to power them.

'57 Ford wiring diagram...
http://www.oldcarmanualproject.com/tOCMP/wiring/5765wiring%20diagrams/Ford/MWire5765-195.jpg

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sorry, yes it is a 57 12 v system. I am using a 6v car battery because I have a spare and I am just using it to test the circuits. I am using a diode gauge voltage regulator for a mustang. As for the ign switch, I am having to merge the Ron Francis kit with a stock wiring set up. The RF diagram is correct but the Ford diagram has these different codes that I don't understand. The gauges tie into I am guessing the Batt terminal so that they get power at all times. I just want to make sure I am hooking them to the correct stud.
 
I don't think you really want the gauges on all the time. That will run down the battery and may get the (original?) gauges too warm.
Their power should be connected to the 'Ignition' terminal so they are only on when the coil & distributor are energized.

In an ideal world... testing circuits using a power source with less current capacity will reduce the chances of vaporizing something accidentally.
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The gauges do work as they got tested when I had the speedo rebuilt. I just want to test the circuit for a split second. If they move great done. I just picked up some alligator clips, 20p fuses and 18 ga. wire. So maybe I can test the dash this week and then reinstall this weekend. Do you think a 6v car batt is to powerful of a power source for this? I am not an electrical person by any stretch of the imagination so correct away…..
 
The fuse should protect you. For what your doing a 5 amp would be fine. Big auto batteries have large amounts of current available. 4 1.5 volt A or C batteries have very small amounts. But with the fuse, you should be fine.

I sometimes use a 12volt “charger” source, powered by plugging in the wall outlet. But some of those don’t give a clean 12 or 6v DC. Those gauges are King Seeley’s. They take a while to move properly. But since they’ve been tested, you probably don’t have to worry about that.
 
Yeah I am just testing circuits so as long as I get juice going through I will be happy. If all goes well the dash will go back in this weekend������.
 
2) On my ign. switch I have BATT/ACC/IGN/START these fairly obvious. But I am looking at the stock wiring diagram and it has the following on the ign. switch AM/S/AC/C. I am thinking that AC is for accessories but what do the other stand for? I am having to blend my Ron Francis kit with some stock wiring.

- TRANSLATION -

509390


509348


509349

I see we are back to the magical disappearing images again ...
 

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AM = Battery
S = Start
AC = Accessories
C = Coil/on
If the dash wiring is installed in the dash already, use the same type of battery that will be used permanently, so if you are going to use 12 volt, use a test 12 volt battery and 12-volt light bulbs.
For 12-volt battery, Connect battery (+) wire to "BAT" term of ignition switch and connect (-) to bottom of dash.
For 6-volt battery, connect battery (-) wire to "BAT" terminal of ignition switch and connect (+) to ground at bottom of dash.
 
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Thanks Dave, once Kultulz posted the diagram I figured AM must be battery. The dash has been totally rewired-except for the oil/gen lights as the dash needs to be in the car first for them to be hooked up. If I have to get a group 29 batt for her then I will. I will have to get one eventually, I just had a 6v laying around and figured that would be good enough to just get juice flowing through the circuit to test them. No big deal. If I am lucky....I can get the dash reinstalled this weekend!!!!!!!
 
So far so good! I have juice going through all three studs on the ign switch, except start as I need another pair of hands to turn the key. I also have juice to the light switch so I am optimistic that I will be able to reinstall the dash this weekend. Baring house chores getting in the way of course��.
 
By now I am pretty sure you have the dash back in but anyway, you don't really need another person to turn the key. Just get you a remote starter switch (they come in really handy) to use whenever you need to crank the engine over or even start the engine.
Just a thought.
 
Yep the dash all checks out and is ready to go back in! I just have a nagging leak around the pass side drain-ugh. So when I finally get it sealed the dash will go in.

Mike
 
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