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Locksmithing 101 | EVERYTHING You Need To Know About The B111 Transponder Key!

If you're looking at getting into automotive locksmithing or automotive key cutting, I want to hook you up with everything that you need to know about the number one transponder key in the USA today, the B111 PT Circle Plus GM transponder key. We're going to tackle what type of chip it uses, what the key blade is, replacement key shells, what the code series is, as well as how to duplicate it. It is because this is one of the most tricky keys out there, which happens to be the most popular, let's get started.

The B111, or the circle plus key, is the transponder key that uses the Phillips 46 encrypted system. The chip is not rewritable so if you were to get one that was programmed already, you cannot harvest its chip pop it into another key shell, and reprogram it.

The blade of this transponder key is known as the Z keyway or the Z profile and the test key to use is a B106.


Now, a test key is just simply a metal brass key that you can use to practice either to use it to cut by code or to practice duplicating on. It's something you're going to want to make sure you have if you're just starting out cutting these keys.


Now, let's talk about the code series. A code series is a specifically assigned set of numbers and letters, or maybe just numbers, or maybe just letters that represent specific key bittings. It also pertains to all of the space and depth information as well inside of that code series. I'll have that listed in the PDF, which will be super helpful for you.

Knowing the code series going to help you kind of navigate your way through getting the job done. This particular key actually has two different code series. However, the first one here represents about 99% of what you're going to see out there in the field, and it's the G0000-G3631. If the key is going to be common, that's when you're really gonna want to memorize.


However, every once in a while like specifically on the Savannah passenger vans or the H2 Hummers, they actually used a different code series. It is the older code series, the S000A-S999k. So that's something you're going to want to watch out for because a lot of times, it's so easy to jump the gun as far as knowing the B111, circle plus key is going to be the actual g code series.


When it comes to key duplication. It is this key that can be challenging because it is an edge style key. You can't align it the same way cause it may start all sorts of problems like miscuts. So I'm going to give you two techniques on how you can cut that key. One just requires zero adapters, you just are going to use your four-way jaws and then I'm going to show you an adapter you can get to help you do it if you struggle. Now, as far as duplicating keys go, these B111 PT or this GMC keyway can cause all sorts of problems. Here’s a way to bypass all of those and make it super simple.


If you have a two-way jaw machine without an adapter there will be two problems. The first problem is that there's not a lot of meat on the bone left on this key when it's cut. So what's going to happen while you're duplicating this key, the key is going to start to come up, even when you go extra careful.

The second problem is even it's straight up and down when you keep clamping it down to get it tight to cut, there will be a  shift at the end.

So those are the two problems, but with four-way jaws like this Nomad. We just move it to jaw three. If you have an Ilco machine or a Silca machine, it's going to be jaw C.

On the left side, look for the groove on the backside of the jaw, put your tip stop, slide your key, and clamp it down.  Do the same on the right with the blank B106 and you’re ready to cut. Once done, flip it to the other side, do the same steps to set it up, and cut.



If you struggle to cut with that method, you can buy these adapters. Put 1 into the grooves of the circle plus key, and 1 to the existing key as well. They're angled to fit. Once done, you can insert the keys to their designated area, left for the existing key and right for the key to be cut. Use your tip stop, slide the keys in, clamp it down, and you’re ready to cut.


And then you're ready to cut. And there you have it! Everything that you need to know about the B111 Circle plus transponder key. I hope you found this information helpful. Make sure you download the PDF in the notes below as a nice quick reference sheet. Thank you and we'll see you next time.

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