100 series master key thread (1 Viewer)

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The remote shell on mine broke last year, went on Amazon and bought a new key blank with remote shell. It was like $15. Programmed it with the instructions from the key programming in the sticky on the top of the page, took all of 5min. Had the new key cut at a hardware store for $3. The replacement is now the master key and I have two valet keys, one of which I also bought off of Amazon and had cut at the hardware store.

This seller has been removed from Amazon, the first key blank they sent me was a cheap knock off, the shell would not close over the remote and it did not have the Toyota emblem on the back. I returned it, the replacement was an original blank, it fits and works perfectly.


309AF174-DFED-491C-AC72-4EA3AD29D7CE.png
 
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I just wanted to chime in with my experience with both the immobilizer situation on a MY2000 LX and with @Mauser himself.

When I bought my LX, it came with only one key; a non-remote, non-master and no wallet key. I read up on the subject, corresponded with Mauser and did the following:

1) Went to my local Lexus dealer with my VIN and proof of ownership. Walked out with my key code.

2) Ordered a pair of these keys from 1010 keys on eBay. The quickly responded with a request for a photo of my lone key. They were able to identify from the photo and my key code that the key I had was a valet and confirmed with me if I wanted the key cut for "full access." The keys arrived and were an exact match and had no issues operating all of the locks. I highly recommend 1010 keys.

3) Got a free, virgin IC900 immobilizer chip from Mauser, who graciously offered them to anyone who needed one. This was also an exact match to the OEM chip on the ECU (centered, horizontally, below the right, red plastic cover):
IMG_20180824_104447.jpg


4) I picked up an affordable rework station from Amazon, did a few practice runs on some old circuit boards and got to work.

5) After reinstalling the ECU, it was automatically in learning mode when I inserted the first key. I followed Mauser's instructions for programming the two masters and valet key.

6) Followed the previously posted instructions for programming the remotes.

7) Installed one of @suprarx7nut 's YotaMD keys because they're awesome.
IMG_20190321_140803-01.jpeg


I've been a happy camper ever since. This was one of those non-critical but very frustrating niggles with my LX. Thanks to Mauser for taking the initiative in helping forum members get it fixed without going the expensive dealer route. I feel a satisfying sense of accomplishment every time I hear the lock/unlock chime and see the lights flash.
 
I only have a valet key! The only option I have to create a master key is to re-flash the ECU correct?
 
A lot of good information on this thread, thank you. I am still lost; I bought by LC with only a valet key (key with no remote functions). What is the cheapest way to get an OEM key fob that controls the locks and starts the vehicle?
I understand that the ECU needs to be re-flashed, but can I do this with Techstream and end up with a fob that works?
 
You cannot reset years 1998-2002 with Techstream. The eeprom needs to be removed and programmed.
 
A lot of good information on this thread, thank you. I am still lost; I bought by LC with only a valet key (key with no remote functions). What is the cheapest way to get an OEM key fob that controls the locks and starts the vehicle?
I understand that the ECU needs to be re-flashed, but can I do this with Techstream and end up with a fob that works?

I really don't think you need a master key to add a remote. They are different ecus.
 
Right on, thanks for the video... so I just need to buy a key online and have a locksmith cut it or do I need additional software to program the key?

I never did answer this question sorry. Yes, you can add keys to the ecu without any software. I will try to add the programming sequence to this thread later today.
 
I too need to thank @Mauser for helping me out with, registering a master in a 07LX.

I only had the valet to work with.
No master.
No door FOB.
No flat Key in a plastic case. Which plastic case, has IM chip.
No tag with key code.

@Mauser and @thabruiser both really helped me out.

I first programmed a door FOB. Which is actually easy. But I had two issues to overcome before I could do this. Took awhile before I realized each issue, thinking I just had a bad FOB from Amazon.

It was very simple to registering door FOB's, once I sorted out the two issues:
  1. 06-07 have a different FOB 12BBT (FCC ID: HYQ 12BBT, IC: 1551A-12BBT). Every signal eBay and Amazon seller I saw, stated the FOB 1512V worked with 03-07, some stated 98-07. I learned the hard way they're WRONG. 06-07 use 12BBT FOB.
  2. My receiver was inoperable. As it turns out, the 06-07 and likely other years share a dome light fuse with: dome lights, seat belt dash warning light, running broad lights, courtesy lights and receiver for the door FOB. Fuse is in the RH J/B (right foot wheel fuse box) DOME FUSE.
06LC Door FOB
 Fob 06LC FCC ID  HYQ 12BBT, 48040 07U18. IC 1551A-12BBT DENSO (2).JPG

 Fob 06LC FCC ID  HYQ 12BBT, 48040 07U18. IC 1551A-12BBT DENSO (1).JPG


Below is 06-07LX. Or was sold to me as a refurbished FOB in a Lexus uncut short key shell, by a locksmith. So I don't know if actually came out of LX.
But it does have one difference in the numbers on the clear side of case vs my 06LC FOB. LC - 07U18 vs LX - 06H2d
FOB HYQ 12BBT, 48040 06H2d from Locksmith Keyless 06-07LX (2).JPG

FOB HYQ 12BBT, 48040 06H2d from Locksmith Keyless 06-07LX (5).JPG



Registering the master key I learned a lot:
There is a web page, that will produce the 96 seed char by inputting VIN # that is needed to get pass code to enter tech stream without a master. This was not available in earlier 98-02 models.
Short and long keys are available. I prefer the short key. Doesn't stick out as far when from IG switch and smaller in my pocket.
Master keys of LX have ridges cut on outside, valet keys do not.
This I knew: immobilizer (IM) chip is in the FOB, and not in the shell of master key.
Lastly: You must have a working cut Master key with transponder (IM) chip to exit the registration program.:doh:
020.JPG


Once done, I tried exiting program with my Valet, as my Master key was not yet cut. It would not allow me to exit program without the master.

I also found that a high end lock smith charges ~$80 to cut a Lexus key. Keys are only $5 to $10.
Lexus sell their first level (they've stronger) key for $50 and cuts it for free.

Both the High end lock smiths and Lexus Dealerships, can take old worn out key and cut new, compensating for ware of old. Lexus Dealership can also get the keys cut code by VIN# and cut without and old key. So makes them a one stop deal. Making Lexus Dealership $50 appealing.
 
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I have an 05 LX with only a Valet and no fob. What are my options? Lexus pretty much told me I need a new master and that it will cost 300. Is that really my only option?
 
You do need a master, but it can be done cheaper. A lot of locksmiths can reset your ecu. If you have techstream you can reset it yourself. If you do it yourself you can probably buy and program 2 keys with remotes for around 50 bucks.
 
I can purchase techstream and then program 2 new master myself without currently having a master? Sorry I'm just trying to get a clear understanding here.
 
I can purchase techstream and then program 2 new master myself without currently having a master? Sorry I'm just trying to get a clear understanding here.

Yes, you will need to reset the ecu. This will require a passcode. I can help with a passcode.
 
Mauser,

You helped me before in getting the proper chip 4D-67 tp29 for the immobilizer. But I can not program the doors. I've tried TS & the open/close door routine over & over but fail each time. I am able to re-program the original FOB using different methods but not the new FOB I purchased.
I think the frequency the new FOB's are not are not the correct frequency.

I don't mind paying for new FOB's but which ones should I buy. This is what I purchased.
ECCPP Replacement fit for Keyless Entry Remote Key Fob Lexus LX470/ GX470 HYQ1512V (Pack of 2)
 
I don't remember the year of your truck. Is it 2006-2007? If it is, it looks like you need a remote with FCC ID: HYQ-12BBT. @2001LC might be able to give you a better answer.
 
06-07 LC & LX are without a doubt 12BBT see post #29, not 1512V.
If the transponder chip in the FOB for immobilize LX vs LC. May or may not be the same, I do not know.
 
Hi Mauser,

I have a '05 LX470. It's in my sig.
Should I try the 12BBT
 
@Mauser, I'll see if I can help him.

It's my understand 98- 05 uses the 1512V door fob/remote. I don't have and 05 here to look at. But if you have your 05 door FOB, in your master key shell. Open the master key's shell and look. It's printed on the door FOB inside of it. Just like on the 12BBT FOBs seen in post #29.
 
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