Coil Splitting Seymour Duncan Hot Rails Humbuckers with a Toggle Switch

coil splitting seymour duncan hot rails humbuckers with a toggle switch

In this article, we’re going to talk about coil-splitting a Seymour Duncan Hot Rails humbucker with a toggle switch. If you’re handy enough to install a toggle switch into the pickguard of your guitar, you’ll find that it’s often the easiest solution for coil-splitting as well as many other modifications.

Seymour Duncan Hot Rails

The following guide will work with any humbucker; you just need to know which wires are which. If you know your exact pickup model, you can Google it to get the wiring code. If your pickup is more obscure, however, you’ll need to use a digital voltmeter to get it. In this guide, we’re going to talk about the Seymour Duncan Hot Rails specifically, so there’s no question about the wiring code.

Wiring Code

The Seymour Duncan humbucker contains four colored wires, and one bare one, which is called the shield. These four colored wires correspond to the positive and negative of each coil.

  • The first coil uses the black wire as the starting and the white wire as the ending.
  • The second coil uses red as the starting and the green as the ending.

The standard way to wire up a humbucker is to run the first coil into the second. So we need to connect the white wire to the red. The shield wire gets connected to the ground wire, which, in this case, is green.

In most cases, the black wire will run to your pickup selector switch. The green and bare wires, which are connected, will usually go to the back of the volume pot.

The Toggle Switch

When coil-splitting a pickup with a toggle switch, almost any type will work. We recommend a two-position switch that has just on and off, instead of a three-position switch. A three-position switch will leave you with two off positions, which is not very useful.

Split Pickup Modification

As we mentioned earlier, when using a Hot Rails humbucker, the black wire typically goes to the switch, and the green and bare wires go to the back of the volume control. This will not change.

Our modification only requires the use of the red and white wires that are already connected. You do not need to disconnect them to complete this mod.

Solder your switch as shown in Figure 1. Your toggle switch may have more or fewer lugs, but it will still solder the same way.

Fig 1

As you can see in Figure 1, we need to add a new ground wire from the switch to the back of the volume control. Now, when we flip our switch to split the pickup, a path is created between the red and white wires and ground. This path essentially shorts out the second coil, resulting in a split pickup.


Coil-splitting a Seymour Duncan Hot Rails with a toggle switch isn’t too challenging, and it can really benefit you with some new tones. If you have more than one of these pickups, you can split them all the same way, by adding a toggle switch and running a ground wire to the back of the volume pot.

We usually recommend using push-pull pots to split the humbuckers because it doesn’t require making any permanent changes to the guitar. However, using toggle switches allows you to use those controls for other modifications down the line. And besides, guitars with a lot of switches can look cool!

We hope you’ve enjoyed reading over this short how-to, and that it has helped answer any lingering questions you may have had. If you’ve found it informative, please feel free to share it on Facebook and Twitter. For more articles on guitar electronics, visit

Our resident electronics wizard came by his skills honestly — first as an apprentice in his father’s repair shop, later as a working musician and (most recently) as a sound designer for film. His passion for guitar led him to Humbucker Soup, where he continues to decode the wonders of wiring and the vicissitudes of voltage. Ed has never taken his guitar to a shop — he already knows how to fix it.