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Wiring From Ignition Switch And Under Dash


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I just bought a '72 2002 on the claim that it runs and I want to make sure it does before I start doing anything intensive, so I'm trying to get it to fire. Step one is getting power. I'm very new to wiring on cars, and I've done what I can to make sense of the diagrams. I have a fresh battery relocated to the trunk, but I don't get any power anywhere at any stage of the key. I currently have this glob of wires hanging loose and disconnected under the steering column. A few things confuse me about this.


1. I cannot find any wires to complete the black terminal. I suppose there would be identical wires on either side of it, and none of the hanging wires match the ones already in the terminal. Is any of the black terminal needed to run the car?

2. I cannot find any male ends for any of the loose wires.

3. The "purple" spade on the ignition switch is empty. I can't find a purple wire in the entire car. What does the purple wire do?


I'm also missing the tray piece where these clips are supposed to live. Supposedly a previous owner used this 72 for SCCA so some stuff might be missing. Any help or pictures would be greatly appreciated. I've read a lot of threads on wiring but I've rarely seen those terminals in the open. I'm just looking to get the thing to start, and other systems like blinkers or lights could come later.




Edited by Dake
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Some of the wiring in your pictures is definitely not factory...so someone--with greater or lesser (and probably the latter) has been messing with it.  

Here's the wiring for a 12 fuse roundie at the ignition switch:

Terminal #    Wire Color            goes to

50                black                  starter--hot only when the key is turned to start

30                red (thick)           battery & alternator--hot all the time

                    red (thin)            light switch (feeds parking/tail lights)--hot all the time

15                green (thick)       fuse #10--hot only when the ign is on

                    green (2.5mm)    terminal 15 on light switch (feeds headlights)

                    green (1.5mm)    plug on dimmer stalk

R                 violet                    fuse #12--hot only when the ign is on

P                 not used

none           wire coming from inside the switch itself--feeds "key in ign" buzzer


That should at least tell you what should end up at the terminals on the back side of the ignition switch...




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not near a car to check, but those black and white connectors look turn signal and wiper related, not ignition. what does the back of your ignition switch look like? that is what you should be looking at and and tracing the wires back from. use mike's list above. check for 12v at terminal(s) 30. if no power there start tracing those wires back. should be easy, they both are red and straight shots to fuse box/alt.

12v to ignition should be easy to trace all the way to the battery. there are only a couple wires and they are all red.

switch removed from column.


testing switch continuity


Edited by mlytle
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Thanks, my main concern was that neither the black nor white clips technically need to be connected in order to get the car to turn on.


P, the turn indicator switch, is used. As per the wiring diagram PDF and the description above, everything but R, the violet / purple wire, is there. I'll try to trace the wires tonight to see where the interrupt is.


Edit: I did get power earlier after tracing the wires to unhooked ones in the engine bay. I installed a fuel pump and coil and got the car to start. Thanks for the help on this one.


Still working on figuring out what the violet wire should be doing, so if anyone knows that answer feel free to chime in.



Edited by Dake
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When you turn the key does the starter crank?, Is there power present at the positive terminal on the coil when you turn the key to the on position? There appears to be some weird stuff going on with your wiring but just getting the engine to start and run is pretty basic but you will need to narrow down where the problem exists.


if you want to just see if the car will start you can bypass the wiring harness very easily and start the engine.

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  • 2 years later...
On 1/11/2014 at 11:43 AM, mike said:

Re the "mystery" violet wire:  check your fuse box and see what that fuse controls...betcha they're all functions that only work with the ign on, so if that's the case, the violet wire is the hot feed to fuse 12.




Edited by Rolling Stone
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  • 5 months later...

im planning to install a ignition toggle switch with a push start button im by passing my push button directly to the starter because i can't start the engine with the key i can only turn ignition on , so now i need to know what color wires i need to connect to the toggle switch to turn ignition on ,, thanks in advance 

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  • 11 months later...

Need a little help- Day 2 under the dash and my back & neck can't take much more.

This is an early 1968 2002 

I'm stumped.  Pulled out Hot Wired Ignition

Rekeyed original Cylinder

Replaced Dead Battery


I had the motor turn over but didn't hear the fuel pump ever get any juice.

Tried moving some wire positions


Now I have nothing except lights :)



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There is supposed to be a mechanical fuel pump on that car so if there is an electric one the wiring isn't stock, no way to know how it is wired. I attached a picture of how the switch should be wired and yours looks to be correct.


The missing purple (violet) wire is for your radio so not really necessary.

starter switch.JPG

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  • 1 month later...
On 3/14/2018 at 9:01 AM, AustrianVespaGuy said:

Also remember when electrical troubleshooting, the clever Germans tried to help you out some: all SOLID colored wires are unfused and can be traced back to the battery (usually via the ignition switch) and all STRIPED wires are fuses and can be traced back to the fuse panel!


This is electrical system gold.


Cut and paste this to your electrical diagrams!

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