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Wiring a universal ignition switch

12K views 17 replies 7 participants last post by  jbeebe 
#1 ·
Hey everyone, i'm still amassing parts for the build that's in the works. Just finished the triple bypass and ready to plop the engine back in with an ignitek and some mikuni's from murray (need to buy still).


I like using universal ignition switches and moving them wherever I want like the one below:

Robot Check

However, according to my first look at the wiring diagram, it looks like I have a 6-wire ignition bundle. Most of the switches are 4 wire, and that's what i've used before. Looking at the wiring diagram, is there anyway I can splice some wiring together at the connector to make the 4 wire ignition work? Or am I stuck using a larger 6-wire ignition switch? I'm using an ignitek.

Thanks!

 
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#3 · (Edited)
You have a multimeter handy?

We'll need to run some tests on the switch to see how it's setup.

I'm assuming the switch only has an on/off setting and nothing for parking lights, so we'll need the following resistance measurements:

With switch on:
Red to black
Red to black/white
Red to green
Black to black/white
Black to green

And repeat the same tests as above with the switch turned off.

Let us know how you get on and I'll give you the next steps.
 
#5 · (Edited)
You can splice the orange/white, orange, and the black together

Orange/white is 12v to you gauge lights
Orange is 12v to your tail light
Black is 12v to everything else

Just be sure that in the off position the black\white has connection with the green wire. This will kill the engine just like the kill switch.

So in off
Black\white ~ green

On
Black, orange, orange\white ~ red

That's six wires down to three
 
#6 ·
Ok guys, I just got the ignition switch in the mail. Of course, it comes with no wire identification.

How do I do a test to see which wires do what? I have a multimeter.
 
#9 ·
Setup the meter to read Ohms.
0 reading mean open, any other reading means that the circuit is active.
 
#11 · (Edited)
Essentially, in the case of connected circuit, the meter will pass current through one pin and detect it with the other. If it's open you won't get squat.

So, if you want something that gives 12v switched power, find a combination of pins that is 'connected' when in the "On" position.

Looking at the wiring diagram linked earlier in the thread, you can see at the top and bottom of the page there are blue coloured boxes.
You can see the top-right box depicts action of the "Ignition Switch". It shows the activity of that particular wire colour (columns) for each of the switch positions (rows).
Using the second example (it's easier to explain), in the "on" position, "red" is connected with "black". In stock configuration, this switches live 12v (red) through the 'switched-power curcuit' (black).
That is to say, anything that stems from the 'switched-power' will only receive power when the ignition switch is "on".

You're just trying to find out which pins on the ignition barrel have what action, so that you can connect them up how ever you want.
 
#12 ·
Thank you very much, that clears a lot of things up. I just needed somebody to explain it out like that. Once I test all of the four wires on the ignition switch, I'll post back the results so that we can figure out what to hook up to what
 
#13 ·
The keyswitch you have is exactly the same as the ones I have on my bikes. It is made to fit the Honda CT70 & CT90. They are about half that price on eBay Switch Lock Ignition Key for Honda JH 70 90 Ct | eBay

Go to this page and learn how to use your multimeter Electronics Club - Multimeters

Building on what dbjac said, you will find that your keyswitch has 2 sets of contacts. One set is shorted (zero ohms) when the key is in the OFF position and open (infinite ohms) when the key is in the ON position. The other set is the opposite - open in the OFF position and shorted in the ON position. I can't remember which wires are which and it is too cold to go out to the garage to check for you when you need to learn how to use your meter anyways


My bikes have TI ignition so I just used the shorted in ON contacts and connected the appropriate wires so that my tail light works when it should. Yours will be a little different but not that bad. In fact, assuming that the schematic you posted is correct for your model/year, it looks like it might be really easy.

I will mention a couple of very important things here that you need to learn if you want to avoid confusion while seeking help on this forum (or most others for that matter):
1) An unlabelled drawing is a useless drawing. When that schematic was copied from a Clymer manual it had the years & models of the bikes it applies to in big letters down the right side (top of the page in the book). With that information removed it could be for anything.
2) You need to do this http://cx500forum.com/forum/general-discussion/31323-forum-settings-everyone-should-make.html You may only have one bike but this forum has a lot of members and nobody can be expected to remember what each one has.

If you don't think we need to know what you have (or at least what it started out as) and know for sure whether that is the correct drawing have a look at some of the schematics in the Wiki (link in my signature) and see just how much difference there is between some of them.

OK, now back to attempting to help
.

In most Hondas of that era you will need to connect the brown wire and the brown/white wire that went to the original keyswitch together to retain tail light function without the PARK light feature.

If you were going to retain the CDI you would need to connect the black/white wire and the green wire that went to your original keyswitch to the part of the new switch that is shorted in OFF. I am not sure whether this is needed with the Ignitec but I believe there is a write up about that somewhere and hopefully you already know where or someone will post a link to it.

You will need to connect the red wire and the black wire that went to your original keyswitch to the part of the new switch that is open in OFF.

As I was typing that I remembered that I connected the red and black wires from my new switches to the matching colour wires that went to the original switches so I would be very surprised if you don't find that you need to connect all 4 of the wires from your new switch to the matching colours. BUT I would want to make sure of which model/year you have and whether that is the correct drawing AND check the switch with an ohm meter before I could say for sure.
 
#14 ·
Thanks for the help everybody, and thanks for the tips Bob.

Alright, I checked the combinations with the multimeter, and the combinations that had a reading in each position were:

OFF: green - white/black

ON: black-red


So does this mean that the green and white/black wire supply the switch with power, and the black and red wires supply power to components when the switch is on?

So looking at the diagram, should I connect the bikes green and black/white wires with the switch's green and white/black?

Then just connect the rest of the bikes wires to the switch is black and red?


 
#17 ·
Alright, I checked the combinations with the multimeter, and the combinations that had a reading in each position were:

OFF: green - white/black

ON: black-red
OK, to start with you will have a reading on your ohm meter when you touch the leads to any 2 of of the wires from the switch. If the switch is clean & working perfectly (as a brand new one should be) the reading will be either zero ohms or infinite ohms. Depending on your meter the indication for infinite ohms will vary but it will generally be the same as when the leads are not connected to anything (this is why I directed you to the Electronics Club to learn how to use your meter).

So what i think you mean is:

the green and black/white from the new switch are shorted when it is OFF and open when it is ON (& not connected to either of the other wires ever - I forgot to mention that
) and

the black and red wires from the new switch are open when is OFF and shorted when it is ON (& not connected to either of the other wires ever)

Which is what I expected you would find. That's good. It tells me that this switch is not really "universal" but was made for a Honda because the wire colours match Honda's standards (other manufacturers use the same colours for different purposes).

(Note that I specifically said black/white instead of white/black as you did. The identical part that I have here matches the pic in the Amazon listing where you bought it and that shows a black wire with a white stripe, not white with a black stripe. This may not seem significant right now but when you progress to other parts of the bike's electric system you may find that there are 2 wires with opposite main colour/stripe colour and it will be easier to deal with that if you develop good habits now.)

To understand what is going on here imagine that there are 2 separate switches inside the keyswitch assembly, arranged so that when you turn the key one way one of the switches (lets call it "A") is on and the other switch ("B") is off and when you turn the key the other way A is off and B is on.

I have a feeling that the schematic seems overwhelming to you but it really isn't that difficult to figure out if you take it one part at a time. In the upper right you will see something that looks like the pic below. It is a representation of what goes on inside the original keyswitch when you turn the key to the various positions, as indicated on the right.
Technology

Starting from the top, when the key is OFF the green and black/white wires are connected together and none of the others are connected to anything. This matches your new switch so you can connect the matching colours.

Next, when the key is ON the red and black are connected together and the brown/white and brown are connected together. The red is power from the battery and the black is the wire that carries power to just about everything on the bike, either directly or through a fuse or switch or something like that. This means that the red and black are connected to a part of the original switch that matches your new switch so you can connect them to the matching colours too.

The last position of the original switch (PARK) is for the parking lights. In some parts of the world you are required to leave lights on at the front & rear of a vehicle when it is parked on an unlit road but that is not required in North America so your new switch that doesn't have it will still be legal. If you were to follow them back through the wiring you would find that the brown wire takes power to the tail light and the brown/white wire goes back to the fuses and some other stuff like instrument lights. That other stuff doesn't have to be on with the parking lights so the switch is set up to connect the tail light (brown) directly to the battery (red) when the key is in the PARK position.

As I said before, you don't need that, but you do need to get power to the tail light when the key is ON. If you connect the brown/white and the brown together your tail light will get power from the same place it does when the old switch was ON and will work normally.

I know this seems like a long way to tell you to connect the wires from you new switch to the matching colour wires that went to the old one and connect the other 2 together but my goal is to teach you how it figure it out yourself the next time.
 
#18 ·
Thanks Bob! I really appreciate you taking the time to walk me through it. This is the first time that i'm really doing electrical things besides just changing out signals, etc.

I'll be posting another thread soon for help wiring in newer CBR handlebar switches....
 
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