Wiring help needed!

Hey guys,
Now that I'm out of school I decided its time to install the new wiring harness. It's a 66 coupe, and I was wondering if anyone has any suggestions.

I'm using Ez Wiring's mini 21. I know that the first step is to document the current connections like in the trunk area is license plate light, turn signal, brake light etc... I'm going to be using the old connectors e.g. the brake light connector to the housing.

I was wondering how do you take out the dash? I looked at the mustang restoration handbook I have and it says that I have to push out the front windshield in order to access the two bolts holding up the dash underneath the front speaker. I really don't want to take out the windshield.
Also, is there a better place to mount the fuse box? or should it be mounted in the stock location?
 
Another question, I found that my license plate lamp was not connected at all, when I looked for its connector i found two in the trunk. One lead to the brake lights and there was a female connector end there, and the there is another wire that isn't connected to anything that has a female connector in the middle and then a frayed end on the complete end. (The frayed and connector one is black.)
Which one connects to the license plate light?
 
My next project after the brakes is to install a new Painless wiring harness, so I'm interested in any feedback on removing the old harness and wiring. I have the windshield out of my ride.
 
You should easily be able to reach all the nuts needed to be able to take off the dash pad without removing the window - in fact, you'll be much better off not removing the window - installing them is a pain.

As for removing the wiring, I just ripped in all out of the entire car - but make absolutely sure to keep everything you rip out until you get your new harness back in the car especially all the connectors for bulbs, etc.

I used a Painless harness, and they are everything but Painless. Painless will proved you with a worthless manual but will not give you a wiring diagram. You will spend plenty of time trying to figure things out and cussing Painless. But it can be done - get yourself a good voltmeter, a good original wiring diagram, and be very methodical. Good luck.
 
You should easily be able to reach all the nuts needed to be able to take off the dash pad without removing the window - in fact, you'll be much better off not removing the window - installing them is a pain.

As for removing the wiring, I just ripped in all out of the entire car - but make absolutely sure to keep everything you rip out until you get your new harness back in the car especially all the connectors for bulbs, etc.

I used a Painless harness, and they are everything but Painless. Painless will proved you with a worthless manual but will not give you a wiring diagram. You will spend plenty of time trying to figure things out and cussing Painless. But it can be done - get yourself a good voltmeter, a good original wiring diagram, and be very methodical. Good luck.

isnt a 65-66 dash welded into the car? I know my 66's dash sure as heck wanst going to come out. There are pinch welds at the front of the door frame that welds the dash in.

The original license plate light was likely tied into the taillights. They figure if you need a license plate light on, you will have your headlight and taillights on.

I would put the wiring harness close to the original spot because the kit is designed to be located around there. I moved the one on my 66 to the inside drivers wheel well and its been a pain having it there.
 
Yah thats wat I thought, or at least i thought there's no way to take out the dash, but i was reading a book and it hinted that you could. If you could it would make the dash wiring so much easier.
K, i looked at the exterior lighting diagram and it makes sense for the most part to me in my mind but when i look at the actual car its like wah...
#1, there is a wire, it has a female connector in the middle and at the end is frayed. The second wire is a female connector in the middle and on either side is connected to the brake lights. I'm guessing this second wire is the one that connects to the license plate light, when I connect it however, it doesn't light up, i'm gonna take multimeter as soon as i can find mine and see if its receiving current, the problem could be the female connector or male even the male one.
#2 The first wire that isn't leading anywhere baffled me, till i decided to look at how the reverse lights were connected, low and behold they weren't! I looked at the wiring diagram and hmm, there aren't any male connectors for the lights they're just frayed wires on both sides. Hmm then i thought ok well this destination-less wire should be the one that is supposed to connect to the reverse lights. when I look at the reverse lights they have a double gauge wire thing, there is two and only one wire is coming from this destination-less wire.
So, how should I connect the reverse lights? twist the two wires coming from reverse lights together and connect em with the destination-less wire?

As for the fuse box, I was thinking of putting it in the glove box. I just don't think where it currently is can be accessed with ease. Then again that glove box isn't very sturdy.
 
Yah thats wat I thought, or at least i thought there's no way to take out the dash, but i was reading a book and it hinted that you could. If you could it would make the dash wiring so much easier.
K, i looked at the exterior lighting diagram and it makes sense for the most part to me in my mind but when i look at the actual car its like wah...
#1, there is a wire, it has a female connector in the middle and at the end is frayed. The second wire is a female connector in the middle and on either side is connected to the brake lights. I'm guessing this second wire is the one that connects to the license plate light, when I connect it however, it doesn't light up, i'm gonna take multimeter as soon as i can find mine and see if its receiving current, the problem could be the female connector or male even the male one.
#2 The first wire that isn't leading anywhere baffled me, till i decided to look at how the reverse lights were connected, low and behold they weren't! I looked at the wiring diagram and hmm, there aren't any male connectors for the lights they're just frayed wires on both sides. Hmm then i thought ok well this destination-less wire should be the one that is supposed to connect to the reverse lights. when I look at the reverse lights they have a double gauge wire thing, there is two and only one wire is coming from this destination-less wire.
So, how should I connect the reverse lights? twist the two wires coming from reverse lights together and connect em with the destination-less wire?

Man..where to start. I would get a decent 12v test light because you will use it. I never mess with a multimeter. What color are the wires that are frayed? Also, Im confused...maybe a simple diagram in MSPaint would help. Most of the wiring in these lights and what not are grouded and use a power wire (on a switch) to turn the light on and off. So the reverse lights can be grounded separately and run a common switched hot, or you can daisy chain one ground to the next. Either way, the power wire should be in series (daisy chained).

You really need an idea of basic wiring and how power flows. This is really a big undertaking because people who dont quite understand will get frustrated very quickly

Look at Tim65GT's link...the diagrams really help
 
Maybe this will help.. I just clipped off the end of the wiring diagrams in Tims link

If you look at the reverse lights...each is grounded independently
The hot source is comes from the harness on the drivers side through the sill channel, over the wheel well and into the trunk. The the hot source goes to the left reverse light and the connector has 2 wire coming out of it. One is the source of the power and the other goes to power the right reverse light.

The license plate light is powered off taillight wire. Its a black wire that goes into the drivers taillight and branches off to the license plate light and then to the passenger taillight.
View attachment 382522
 
oh gotcha, so for the back up lights just use that stray wire to connect to one side of two wires and the other side as a ground.
Edit: I just looked at the wiring schematics for the exterior and now it makes total and complete sense, thanks. Will try it out tomorrow

Edit: found out the problem with the lic. light, didn't touch the bumper so it wasn't grounded ugh...
 
My 2 cents....


Go ahead and buy the headlight switch, ignition switch, and wiper swtich from EZ Wiring.

I did exactly what you are doing and when it came to wiring those things to the ford switches, it took a lot of trial and error and this forum to get them wired correctly.

The EZ Wiring harness is a GM harness so those particular switches are not particularly easy to connect to it.


When I did mine, I ripped all the wires out
Wired the engine compartment and front lights first
Moved to the back of the car
Wired up all the above mentioned switches
and finished with the dash / gages etc...

That is a great Harness by the way. I think you made a wise purchase. I can't fathom what makes the painless harness worth $500 more.
 
Ya I've heard the switches problem from a few different people. I'm tryng to make sense of it all in my head before I actually start pulling wires out of the car. I've printed all the wiring diagrams provided, and now I am matching them with the new harness, just looking at what is on the harness for example color and the # on each wire and assigning the diagram the new color and #.

If something doesn't make sense I can come here to the forums and ask. As for buying the switches, I want to keep the car as stock as possible, I'm gonna try with the stock switches and worst come to worst I'll switch em.

Speaking of things that don't make sense, the charging system, Can someone explain to me what the two things circles are? Are they both the starter relay?
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Edit:
Question 2: This might sound stupid but, for example the brake lights, Theoretically, there should be one set of wire going to the brake light switch wherever that is, steering column or wherever, which has the wire then going to the fuse box, then then there will be a wire leading to the tail section connecting to the tail lights?
 
The one on the left is your voltage regulator. It is likely a black box about the size of a rubick's cube w/ wires running to your alternator.

The one on the right is your starter ssolenoid. It will be wired directly to your positive battery terminal.
 
Your brake light switch it on the brake pedal near the top of the arm under your dash. That will just be plug and play. I think one is marked brake power and the other brake switch

There are wires leading to the tail labeled L Brake Light and R brake light and third brake. Also the turn signals go back that way.

I ended up (Due to the complexity with which the headlight switch, turn signal switch, brake lights, turn signals, brake light switch all hook up) Adding a second set of bulbs to my tail light buckets and using the third brake soley as the brake light rather than integrating w/ the turn signals.
 
Thanks for clarifying the markings.
As for the brake switch, So basically power goes to the switch from the fuse, when you push it, it allows the current to go onto another wire back to the fuse box and then relayed to the two brake lights?

Also, so when you guys were talkn about connectors being reused, does that mean the main disconnects are also reused? and you just splice the new wires to fit with the old endings?
 
suki243
Thanks for clarifying the markings.
As for the brake switch, So basically power goes to the switch from the fuse, when you push it, it allows the current to go onto another wire back to the fuse box and then relayed to the two brake lights?

The current from the switch doesn't go back to the fuse box. It goes on to the directional switch in the column then to the brake/signal lamps.