Wiring a toggle switch

[mjoekingz28]

I have red and yellow wires coming from my roof marker lamps on my 2500 Chevy. I remember cutting some wire under the dash a while ago and the lights no longer illuminate. The toggle has a red wire connected to the middle spade. The top and bottom spades have no wire terminated there. I found two points under the dash where yellow wires are terminated at a screw. So I assume red is 12v and yellow is ground.

Does the toggle need another wire attached in order to work?

I used to do a little bit of 12v so I assume that both bare spades on the toggle are the same- it is just that one is for on/off and the other side would be for off/on. The lights on the roof appear factory, but the toggle switches and the red/yellow wiring appear backyard.

Also, a electric trailer brake module is right in this area. It seems like a factory setup, but has an aftermarket name on it, which seems odd but then again this is my first Heavy Chevy.

Thanks in advance guys!

 

[WyrTwister]

Put it all back the way it originally was and leave things alone if you do not know what you are doing .

 

[Chris142]

The 3rd wire could be to light up the switch.

 

[Linctex]

Originally Posted By: mjoekingz28
I remember cutting some wire under the dash a while ago...


WHY?!?!?!

Originally Posted By: WyrTwister
Put it all back the way it originally was and leave things alone if you do not know what you are doing .


AGREED!

 

[tmorris1]

You probably shouldn't be running all the current through the switch either. Might need a relay too. If you are unsure how to wire a toggle, I would have someone else look at it.

 

[EdwardC]

A couple possibilities here:

1) It's a lighted toggle switch (like mentioned above). In this case, you have a constant 12V connection to one terminal, a ground for another terminal, and a switch 12V output to the roof light.

2) If it's not a lighted switch, it's likely a Single Pole Double Throw switch. In this case, you have one input (likely the middle terminal), and the switch toggles between connecting the middle terminal and the right terminal, and the middle terminal and the left terminal. In this case, you need to connect one of the two terminals to the +12V connection of the roof light. I am assuming that the roof lights are grounded locally to the body already.

 

[emmett442]

Lit vs unlit switch has nothing to do with it. As mentioned by Ed, there's a constant supply power, a ground, and a switched power.

 

[Donald]

Make sure there is a fuse somewhere in the circuit.

Remember in a house black wire is hot, so is red if there is one. White is neutral. Green is ground.

In a car or boat with DC wiring, red is hot, black is ground. White will be hot also.

 

[mjoekingz28]

You are correct. It does have a bulb. I did tbis to my RX-7 back in 07-08 right when I joined here. I got upset at the cobbled wiring job of the aftermarket cruise control and got out the wire cutters and went to town. For some reason I cant stand an unprofessional wiring job- yet, I cant do a decent one myself. I will probably ha e it seen to by someone to get it working. It all started when the driver's side bulb wouldn't illuminate. Then after some work done it would, but sometimes needed shaking to get a contact. It has pretty much been inop fo awhile now. I may ask the dealer when getting oil cooler lines, a truck accessory store or a car audio installer.

 

[SHOZ]

There would be no ground on a toggle switch unless it has a light. Or it is switching ground instead of 12v+.

 

[The_Nuke]

Your post is a little hard to follow. I am going to break it down into disparate sections so I can reply to each one and make sure I'm not making the wrong assumption about what you are asking and the situation you are facing...

Originally Posted By: mjoekingz28
I have red and yellow wires coming from my roof marker lamps on my 2500 Chevy.

How many lamps are there?

Do they all have the same red/yellow wires?

If so, can you remove one of them and/or completely detach it so that it can be tested away from the vehicle (like on a work bench or something?

Originally Posted By: mjoekingz28
I remember cutting some wire under the dash a while ago and the lights no longer illuminate.

Why were you cutting wires under the dash?

Did you install something?

If so, what was it?

If so, is it still there?

If so, does it still work?

Originally Posted By: mjoekingz28
The toggle has a red wire connected to the middle spade.

What toggle?

Did you install this toggle?

Assuming it is meant to turn the roof lights on/off, can you remove it from its mounting location for testing off the vehicle (and on a workbench or something)?

Originally Posted By: mjoekingz28
The top and bottom spades have no wire terminated there.


Okay, that's probably significant somehow if the toggle is supposed to operate the roof lights. Best way to know how is to remove it and test off the vehicle (like on a workbench).

Originally Posted By: mjoekingz28
I found two points under the dash where yellow wires are terminated at a screw.

Okay, are they the same yellow wires that come out of the roof lights?

Originally Posted By: mjoekingz28
So I assume red is 12v and yellow is ground.

That is a reasonable hypothesis, but it would be foolish not to test it out and verify your assumption.


Originally Posted By: mjoekingz28
Does the toggle need another wire attached in order to work?

I don't know. Probably, but the only way to know for sure is to test it out, which is best done when detached and away from the vehicle.


Originally Posted By: mjoekingz28
I used to do a little bit of 12v so I assume that both bare spades on the toggle are the same- it is just that one is for on/off and the other side would be for off/on.
That does not sound right to me, but I could be wrong. Best way to know for sure is to remove the switch and test it out.

The lights on the roof appear factory, but the toggle switches and the red/yellow wiring appear backyard.

Toggle switches? As in, there is more than one toggle switch?? (if so, this is could turn out to be a very strange case indeed!)

What about the wiring appears backward to you, the colors? Or do you mean they just don't match what you would expect?

Originally Posted By: mjoekingz28
Also, a electric trailer brake module is right in this area. It seems like a factory setup, but has an aftermarket name on it, which seems odd but then again this is my first Heavy Chevy.
Thanks in advance guys!


The vehicle's make and model shouldn't come into play with an electrical issue, especially if it is an non-factory wiring and installation job. Basic electronics theory should be the governing rule-set here, not any proprietary set of propensities that individual auto-makers might use in building their respective vehicles.

If you could take some pics and post those up, that might help out a great in understanding what you are referencing in this thread.

Nuke

 

[The_Jeff]

^ Agreed.

I assume the roof lights are not stock.

I do not know why they aren't wired in with the parking light circuit to come on automatically.

The parking light circuit and/ or the dimmed instrument lighting circuits often go to the stereo, so it's a natural place to tap into for aftermarket use.

Wire color is barely relevant, as it sounds like some hack just found some random yellow wire to use.

The middle spade of a switch could mean it's an on-on switch, with the middle spade being common. The outer spades will pass power, one at a time. One plausible wiring scenario is to have always-hot and sometimes-hot coming in on the outer spades then having it go out the middle on up to the lights. But you need to diagnose this.

You'd do well getting the $0-5 harbor freight multimeter before continuing. It can test ohms (whether a switch is open or closed) and volts, which may or may not be present.

 

[tmorris1]

Originally Posted By: Donald
Make sure there is a fuse somewhere in the circuit.

Remember in a house black wire is hot, so is red if there is one. White is neutral. Green is ground.

In a car or boat with DC wiring, red is hot, black is ground. White will be hot also.

You always need to test. Colors mean nothing. Its like saying all firetrucks are red.