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TOY43AT4 Transponder Key | Everything You Want to Know

The TOY4384 Toyota key is an older Toyota key, but there is some information that if you don't know and are not prepared for will catch you off guard.

Depending on the vehicle, this particular Toyota key was used in 1998 until right around 2005. The TOY4384 key is actually part of the Toyota transponder family, the TOY44D, TOY44G, and TOY44H. As a matter of fact, if we put them all together, you can see that they essentially all look the same. From the head shape up to the key blade is the same. The good part is that once you start to understand these Toyota transponder keys, the information will start clicking for you.


Now, before we get to the good stuff, let's go over all the basics and make sure we're on the same page.


The chip that's used in this key is the Texas Instruments 4C. This is a fixed code, it's not an encrypted one so you can reprogram it.


The test key is TR47 key. It uses the same test key as the TOY44D, TOY44G, and TOY44H.


Look for JMA part number TP00TOYO-15.p as key shell. The good news is all of that the test key and the chipless key are the same with what you would want to use for the TOY44D, TOY44G, and TOY44H. So if you're smart about it, you can limit the amount of extra inventory you need to carry because the difference between those keys is just going to be the chip. That way, you can just stock the actual keys themselves but when it comes to your backup stock, you only need to stock one shell and one test key to fit all of them.


When it comes to the code series, there are two different possibilities, 10001 – 15000 and 50000 – 69999. If you're decoding locks, pay attention to the key code because it is important.


When it comes to duplicating these keys, make sure you master how to duplicate this keyway. It is so crucial because this keyway is used so much by Toyota. The sooner that you get it down and feel comfortable duplicating it, it's going to make your life a little less stressful.

Securing the key into the jaw

Your standard practice is to put the key like the image below since it has a decent amount of meat at the end.


But if you are a little nervous, depending on the cuts, you can always slide it all the way up to the tip stop at the end. That's going to give you that extra security as far as  material to grab on to the key. 


If you have two way jaws, something that happens a lot is that the key start flying out. And so Ilco makes these adapters. These adapters has to put it on one side of the key way. It sits in that key way groove and flattens a side.


Put it in face down, and instead of putting it on the groove, you just put it all the way into the machine. Cutting it like this is essentially the bullet proof way to do it.


So if you struggle with these, or you wanted to choose the adapters, they are available. They're pretty inexpensive.

Install the test key to the other side by using the process when installing the key that you need to duplicate. When cutting, use the shaving technique. Do not hit each cut all the way down, shave it halfway through, then come back and get it again.


Flip the key, follow the procedure when installing the key, and cut the other side.

There you have it, that's how you can cut the TOY44D or any TR47 key on side A or side 1 with or without the adapters.


Let's talk about what I believe as the most important thing to know about this transponder key. It can kind of catch you off guard if you don't know this information. 

When it comes to programming, there are:

  • onboard programming;
  • key programming

Onboard Programming

If you have one or more existing keys, you'll be able to onboard program it. It's a very simple routine. You can even erase all keys and program them all again. As far as that, functionality is very simple.

Key Programming

Back in 1998 on these Toyotas, they did not have a OBD2 port. To key program these Toyotas you have to pull out the ECU.


Take it apart and flash it. Either use an old school EZ flasher, or even the AutoPro pad, clip-on and do it.


I've done several of these with the EZ flasher. It's not difficult, but it is definitely intimidating the first time that you do it. So if you're going to be accepting calls for all-keys-lost, you have to make sure that you have ECU flashing equipment to make sure that you can get the job done. If you want to know more about that, give us a call. We'd be happy to talk to you about it.

There you have it; all the info on the TOY4384. Share us your experience when it comes to onboard programming and pulling out the ECU and flashing. Thank you, and we’ll see you next time
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